The Naturalist’s Microscope Guide Part 1: Stereo Microscopes

When thinking of the varied toolkit of the enterprising naturalist, a microscope is perhaps not the first thing that springs to mind. Nevertheless, for many entomologists, botanists and comparative zoologists, the ever-reliable 10× hand lens eventually proves insufficient. Indeed, many species of insect, lichen and fungi (among many others) are difficult to identify past genus or even subfamily without the use of more powerful optics. Animal scat, small mammal dentition and hair fibres can be likewise difficult to evaluate without suitable magnification. But researching the best optical equipment for your purpose can be a disheartening task, especially for naturalists who are likely to come across a wide range of resources for the engineer and medical professional, but sparse pickings tailored to their own specific needs.

For most naturalists, the 3D image and relatively low magnification of the stereo microscope (also called the low-powered dissection microscope) fits the bill nicely. However, with several big-name brands, a wide range of price points and numerous specifications available for uses across a plethora of fields, it’s useful to be armed with some background knowledge when choosing your own microscope.

Stereo Microscopes

Stereo microscopes are made up of several parts: most include a base with or without illumination, a pillar with an adjustable bracket for the head and a head comprising of two eyepieces and one or two objective lenses, depending on whether the microscope uses the Greenough or Common Mains Objective design (discussed below). Some also include a third eyepiece or ‘photo tube’.

ultraZOOM-3 Stereo Zoom Microscope

Specifics regarding the different parts of the microscope will be discussed later, but for now, it is important to understand how magnification is calculated. The optics of a stereo microscope consist of two eyepiece lenses and one or two objective lenses with which they are paired. Each provides its own zoom – typically 10× for a standard eyepiece and 2× or 4× for the objective (although many objectives provide a range of magnifications between 2× and 4×, see below). The overall magnification is calculated by multiplying the objective and eyepiece lenses together, for example a system with 10× eyepieces and a 2× objective will provide a zoom of 20×. Some objectives have a dynamic zoom lens, as we’ll discuss later.

Optical Systems: Greenough vs Common Mains Objective

Stereo microscopes are grouped by the optical system that they use – Greenough or Common Mains Objective (CMO). Both systems have distinct advantages and disadvantages, so knowing the difference is vital.

A staple since its original conception in the 1890s, the Greenough Optical System works by angling two objective lenses towards each other to create a 3D image. The objectives have wide apertures for good light-gathering potential, providing a crisp, clear image. It is also cheap to produce, meaning that most entry- to mid-level stereo microscopes utilise this design. However, as the lenses are slightly tilted, the focus is not constant across the image – the outer left and right portions of the view are always slightly over-focused while the centre is clear. This is known as the ‘keystone effect’, and while it is often unconsciously corrected for by the human eye, it does cause the viewer to experience eye fatigue more rapidly than the alternative.

Introduced in the middle of the 20th century, the Common Mains Objective (CMO) system uses one objective lens that is shared by both eye pieces, allowing for exceptional light-gathering potential, and eliminating the keystone effect. However, the single objective leads to a problem known as ‘perspective distortion’, in which the centre of the image appears to be elevated like a fish-eye lens. Models that correct this can cost thousands of pounds, so for many naturalists, a high-end Greenough system is likely to be a better investment than a low-end CMO microscope.

Magnification

Once you’ve decided which system you would like to go for, consider the magnification. Most microscopes under £1,000 fall into the 20-40/45× range. Occasionally 60× models are offered in this bracket, but it’s definitely worth testing these before purchase as the extra range can come at the cost of features such as lens quality. Remember too that as zoom increases, the aperture of the lens decreases, making the image worse. For most insects above 2mm, a 20×-40× microscope should do the job. Groups that rely on minuscule features or genitalia dissections may require higher magnifications, but this often requires a better-quality microscope that uses high-quality parts to maintain a clear, bright image.

20x and 40x magnification of a Green Dock Beetle – Gastrophysa viridula

The cheapest stereo microscopes use a ‘fixed’ zoom system, with a single pair of objective lenses that provide one magnification, normally 20×. The objective (and sometimes the eyepieces) can be removed and replaced manually with a higher magnification alternative.

Models above the £150 mark generally use a rotating ‘turret’ system shared with compound microscopes. Two pairs of objective lenses are included and can be rotated into place, generally 2× and 4× allowing for 20× and 40× magnification. For the serious amateur naturalist looking to invest in a ‘workhorse’ style system, this is often the design to choose, and many professional entomologists and botanists spend years learning with such an optic.

Finally, stereo microscopes above around £300 generally use a dynamic zoom system. This allows the magnification to be altered across a range (normally 20-40×). The default 10× eyepiece can be swapped for a greater magnification if desired. Many also include a ‘click stop’ system for easy reading of the magnification without having to look up. The flexibility of these microscopes makes them the most popular choice among many naturalists.

The Head: Binocular vs Trinocular

This is simple but important to consider. While the binocular head is generally considered to be the default for stereo microscopes, the trinocular variant is extremely popular among researchers and anyone who seeks to document their microscopy: the addition of the third eyepiece (phototube) allows for a camera to be attached and images or video to be captured while the user is viewing the image. Many microscope cameras are designed to be used specifically with a phototube and will not function when used with a binocular head. Some, like the Moticam X3, can be used with either.

The Stand: Base, Stage Plate and Illumination

When choosing an illumination system, it is important to consider what you’ll be using your microscope for. You’ll often see plain (no illumination), halogen, or LED bases offered, with the plain option being the cheapest and LED the most expensive. Most illuminated bases offer both transmitted and reflected illumination, referring to the way in which light reaches the eye. The reflected system utilizes a light that shines straight down on the subject, reflecting the light off of the subject and into the user’s eye. This is the most commonly used design among naturalists, as the examination of opaque objects such as insects, plant material and mammal hairs requires the user to observe the sample’s upper surface.

Transmitted illumination utilizes a bulb beneath the sample, projecting light directly to the user’s eye, similar to a compound microscope. This is used in the examination of translucent samples such as aquatic invertebrates and some macroalgae.

This is also where stage plates come in. Sitting below the subject as the ‘background’ of the image, most microscopes come with opaque black and white options for use with the reflected illumination setting and a frosted glass option that light will shine through for use with transmitted illumination.

Motic ST-30C-6LED Stereo Microscope

Don’t immediately discount a plain base. Many naturalists prefer not to use built-in illumination that sits directly above the subject, as specimens that require the examination of fine details on the sample’s surface, such as many beetle species, can be difficult to ID under such a light. The best solution is to purchase a dedicated microscope illumination unit, a handy tool that usually includes two swan neck LEDs that can illuminate the subject from whichever angle is most auspicious. These aren’t cheap, but the cost of one is often covered by the money saved in purchasing a base without a built-in light.

Finally, consider the difference between halogen and LED illumination. For many purposes, such as the examination of bones, animal hair or water samples, this is irrelevant and largely comes down to a matter of taste. However, some materials are prone to desiccation under the heat of a halogen lamp. Therefore, particularly for entomological work and work involving live samples, LED illumination is often preferred.

More Information

The array of options that go alongside buying your first microscope can be daunting, but with a little consideration, you should be well set to explore the wonderful world of the tiny. Keep in mind your budget, and the microscope’s intended function, and you won’t go wrong. The information in this blog should be a strong starting point, but if you should want any more advice, feel free to get in touch with our friendly team of Wildlife Equipment Specialists via customer.services@nhbs.com or phone on 01803 865913. Our full range of stereo microscopes can be found here.

NHBS In the Field – Browning Recon Force Elite HP4

Fast becoming one of our most popular trail cameras, the Recon Force Elite HP4 delivers outstanding quality video, super-fast responses and some great new features, all for excellent value.

The model joined the ever-growing suite of highly regarded trail cameras offered by Browning at the start of 2021. What sets the Recon Force HP4 apart is that, while introducing some useful new settings and providing generously rich image and video resolution, it doesn’t stretch the budget too much, the way some of the higher-end trail cameras currently do.

With the HP4, Browning has successfully found a way to keep the cost of a top specification camera reasonable without compromising on any of the quality they are renowned for. After some time experimenting with this camera, we feel sure that it is set to become one of our most desirable models, fulfilling every need you would have for a trail camera.

As is the case for most of the high-spec Browning trail cameras, the HP4 includes a front-facing colour screen, but at a bumper 5cm in size, this screen really is ideal for reviewing footage while in the field, particularly if you are capturing smaller wildlife. It also can’t be stressed enough just what a great aid this large screen is when setting the camera up, as it is so much easier to check that the camera’s positioning, angle and height are all set as desired before deployment.

Despite increasing the screen size, Browning has still managed to reduce the overall size of the camera itself, which is handy when it comes to transportation, discreetness and ease of attachment to trees. The back of the camera features a sturdy metal bracket for threading a strap or cable lock through, as well as the usual tripod screw on the underside, giving you plenty of options for mounting the camera.

Some of the more notable features of the HP4 include its smart IR video, which continues capturing video as long as an animal continues to be active in view of the camera, with recordings lasting up to a maximum of 2 minutes in daylight and 20 seconds at night. Its SD card management function is another useful addition, providing the option to overwrite older images on the card if the memory gets full.

Using its top-quality specifications, the Recon Force HP4 reliably and beautifully documents the wildlife you wouldn’t normally see and is both versatile and affordable enough that it should be suitable for most circumstances.

How we tested

For an insight into the camera’s performance and its suitability for different circumstances, we used the camera in a variety of habitats where the behaviour of different wildlife could test the camera’s range of functions. After setting the camera up with a full set of AA batteries and a 32GB SD, we first focused on smaller mammals by using the camera in a low canopy broadleaved woodland setting. We used a Python Mini Lock to secure the camera to a suitable tree and positioned the camera overlooking a small woodland clearing where a few peanuts were scattered. We left the camera out here for two days and nights under the following settings:

Mode: Trail Cam; Photo Quality: Ultra; Photo Delay: 1 Secs; Multi Shot Mode: Off; Image Data Strip: On; Motion Detection: Long Range; Trigger Speed: Fast; IR Flash Power: Long Range.

The camera was then moved to a more open garden setting, where we focused on video. We set the video length to 10 seconds, but also turned on the smart IR video function.

Motion tests were performed before leaving the camera running, which is a very convenient feature to ensure that the triggers are operating as expected before deployment. This simply works by checking that a red low glow is emitted when waving your hand in front of the camera.

We also tried out the programmable stop/start timer, which informs the camera to only trigger during specified timeframes. This is another very useful feature, especially if, for example, you are targeting only nocturnal or diurnal wildlife or baiting a site and wanting to avoid excess triggers from unintended species that may be attracted to a bait during the day/night.

What we found

Under these settings, the camera captured significant activity from brown rats at night and grey squirrels during the day. In terms of still images, which are captured at 22MP, we felt that the quality, colour contrast and detail recorded is fantastic and the black and white IR images were not too grainy.

It was interesting to see that with the 1-second photo delay, whole sequences of squirrels finding and then burying peanuts in front of the camera were nicely captured, just like a broken-down video, showing the camera wasn’t missing any action in front of it.

Even when a fast-moving squirrel was leaping in and out of frame, most of the images captured were sharp, showing the value of the impressive fastest trigger speed setting of 0.2 seconds (s). It is worth noting, however, that this fast trigger speed did result in many captures of animals just as they were entering the field of view, rather than more in the centre.

In response to this, we adjusted the trigger speed to the slower 0.7s to see how this affected the captures going forward. This resulted in some captures of rats further into the centre of the image. Also, when a slow-moving domestic cat approached the area, the first capture was made once the cat had made its way into a fairly central point of the frame, resulting in a more useful image. This demonstrates the value in having an adjustable trigger speed, which allows the user to customise the set-up to the particular circumstances or the habits of target wildlife.

The Recon Force HP4 boasts a great infrared sensor with a detection range of 34 meters and utilises new long-range LEDs, so it was very encouraging to see the camera triggering when a rat was passed by at approximately 5 meters away, outside the main detection zone and partially obscured by leaf litter. Although we have not yet had a chance to put the full detection distance to test, we already feel from these captures that the detection and trigger speeds can be relied upon.

It is worth noting though that for small mammals and birds, they can often be a challenge to identify unless they are triggered very close to the camera and within the core detection zone.

When testing in the garden setting, we hoped to capture foxes but instead recorded several domestic cats alongside garden birds. Here we decided to also test the smart IR video which worked well and resulted in 20-second night videos of cats sniffing around while they remained in view.

This setting proved particularly helpful when the camera was later returned to the woodland and was triggered by a passing badger. The recording did not end until the badger had fully left the frame. Using this function therefore greatly reduces the risk of interesting behaviour being missed just because a video has been timed out by default.

After reviewing the video footage, we were first struck by just how sharp and smooth the quality was at 1920 x 1080 taken at 60 frames per second, revealing plenty of detail both during the day and at night. The level of detail produces attractive footage that could perhaps help with the identification of individual animals.

It was also a pleasing result that we found no false triggers under both the long and normal detection range and the fast and normal trigger speeds, even under some windy conditions.

Our opinion

We would have no hesitations in recommending the Recon Force HP4 for both serious naturalists, researchers and even a first-time user looking to capture reliable and quality footage in their garden or local area.

Certainly, one of the most practical features is the large 5cm colour screen which really does make a difference to set up, alongside the no-nonsense menu navigation and instruction manual. Even those that are not so technically minded should have little problem using and enjoying this camera. Large front-facing screens are by no means unique to this model, but most others are usually significantly higher priced.

The super fast picture trigger and recovery speed of 0.01s and 0.6s respectively and video trigger and recovery speed of 0.38s and 0.7s, shouldn’t fail to capture anything, but the trigger speed is adjustable which is great for flexibility. Depending on the circumstances of your detection zone and what wildlife you are targeting, switching to the slower trigger speed could be more convenient, for instance for recording slow-moving large mammals, so this function covers you for all options.

One aspect to consider is that it lacks a hybrid mode that would enable both video and still images to be captured simultaneously, which can be useful in many circumstances. It is also worth being aware that the HP4 is a red ‘low glow’ camera, and the discreet red light emitted during night-time triggers did appear to draw occasional minor attention from some wildlife on occasions. But as is often reported, most wildlife is not spooked or adversely affected by this, so the most important reason to opt for a No Glow camera instead would be if using the camera in public areas.

The field of view is 40.2°, just slightly narrower than that of a similar model, the Browning Strike Force HD Pro X. Based on our findings however, it is hard to see that this minor difference will have any significant impact on your success rates.

We found that the images and videos captured during the depths of night were particularly impressive and significantly less grainy than many older models. The sharpness and colour contrast is very aesthetic and allows for details such as fur texture to be visible on even the smaller animals.

Other highlights we found included the relatively wide range on the adjustable trigger speed, and the smart IR video which made the most of the behaviour being captured.

To conclude the HP4 is an outstanding trail camera that builds on Browning’s long-standing reputation for durable, easy-to-use and high-performance trail cameras. Even if you are considering a more entry-level trail camera, after seeing the quality of videos this camera produces it would be hard to resist not treating yourself to this camera as an upgrade, given its price.


The Browning Recon Force HP4 can be found here. Our full range of trail cameras can be found here.

If you have any questions about our range or would like some advice on the right product for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

 

NHBS In the Field – Garmin GPSMAP 66s

The GPSMAP 66s is one of Garmin’s most advanced handheld GPSs. Originally released in 2018, the 66s builds on the success of earlier models to provide the best tracking possible, along with a plethora of other features and improvements.

Handheld GPS devices are used by researchers and ecologists in situations where there is a need to create or follow a particular route (e.g. a transect survey) or where there is an area of interest (e.g. a bat roost) that may need to be marked for later analysis or to allow the surveyor to return to that spot in the future.

Outside of environmental monitoring and research, handheld GPSs are primarily used by walkers, hikers and cyclists looking to plot and record their routes. In late September, I tested the usability of a Garmin GPSMAP 66s by taking one with me on an eight-day walk along the Cotswolds Way – a national trail covering around 100 miles from Chipping Campden to Bath.

How we tested

Setting up the path on the GPS

One of the most important things to understand with all Garmin GPS units is the difference between a “track” and a “route”. The published literature from Garmin does not do a great job of distinguishing this, but thankfully there are a few superb YouTube videos that helped clarify the distinction between these terms and allowed me to choose the most suitable option for my purposes.

Routes: Designed to help guide you along a strict path, similar to a Satnav in your car. A route is made up of a number of waypoints (coordinates) placed typically at places where the user would have to change course or direction – this means that more complex routes require more waypoints to provide accurate navigation (hiking trails in remote areas, for instance, would most likely need more waypoints than driving in the city). When following a route, the GPS gives you on-screen advice about the direction you should be heading to reach the next waypoint and can alert you when you need to be aware of an upcoming change in direction. The two major drawbacks I found when using routes for my purpose were that the dense number of waypoints required made the screen almost unreadable and I did not need or particularly want the device directing me exactly where to go the entire time.

Tracks: Designed to show you on a map where you or someone else has been previously, like drawing a line on a map. A track is in principle far simpler than a route. The GPS inherently has a running log of your current activity, including your location which is displayed on-screen as a cyan trail across the map you have loaded. When you are done with that period of activity, you can save this data as a track if desired. When needed, you can load this track and it will display your previous path on screen as a red line, which you can then use to navigate. Tracks, however, do not provide active navigational assistance; when you have a track loaded, the GPS will not direct you to go one way or the other and it will not alert you if you deviate at all. In my case, I did not want instructive navigation and the visual clarity offered by a track when compared to an equivalent route meant this was far more appealing to use for my walk.

Once I had decided the system I was going to use, I was able to easily find a track of the Cotswolds Way online. Tracks and routes can be exported from or imported onto your GPS as GPX files. A handy tool when checking a route or track is Garmin’s BaseCamp program. This free software can be used on your computer to view routes/tracks, add in waypoints and transfer files to and from your GPS. I used BaseCamp to make sure the track I found looked suitable and I also added in a few waypoints to mark specific points along the walk, such as our accommodation and a few shops. You can customise the icon and name of these waypoints to provide the best denotation, and additionally, you can add notes to each waypoint (particularly handy for noting down the contact details of accommodation).

Using the GPS

The GPS was able to operate for approximately 25 hours on the walk before needing to replace the batteries, so for my purposes, I only had to carry one additional set of batteries to power the GPS for the whole 8 days.  The GPSMAP 66s comes with a carabiner clip piece, which is easily slotted onto the device. This was very convenient as it allowed me to attach the device to the outside of my backpack, meaning I could easily check the device without having to worry about it falling out of a side pouch. I ran the GPS for the duration of each day’s walking and saved these as individual tracks, which I later combined in BaseCamp for the purposes of this article.

What we found

I found that using the GPSMAP 66s was slightly intimidating at first as there are a lot of settings and it can be easy to push the wrong button and end up on a different sub-menu. However, I put a bit of time aside before we started to allow myself to test using the device, and this was enough to help me resolve a few small issues I was having.

On the walk, I found the GPS was easy to use and very handy. Turning on in the morning and saving the track at the end of the day’s activity is fast and simple, and having the on-screen route was an incredibly handy reference in areas where the written directions were unclear, or the route signage was lacking. My unit came with the TOPO Great Britain PRO Bundle, which includes Ordnance Survey maps of all Great Britain, and this was very helpful in getting a quick detailed picture of the surrounding area. This was of great help in one instance where we needed to find a safer alternative route to our accommodation to avoid a rather unpleasant walk along the A436.

One unexpected benefit of the GPSMAP 66s was the reward of reviewing your activity at the end of the day on the GPS. The device will give you a summary of your walk including interesting data such as your average movement speed, total elapsed movement time and, thanks to its built-in barometric altimeter, your total ascent and descent (also visible as an elevation graph). Being able to see these data after a particularly exhausting day was a fantastic morale boost!

The saved individual tracks were easy to import back into BaseCamp and, once imported, I was then able to merge these to form an overall track of the entire route. This is a very nice feature as you are then able to view your entire route and you are provided summary data along with this. One slight issue was that the summary data did not initially update properly, showing just a single day’s activity rather than the complete walk. However, deleting a single point of data was sufficient to kickstart the program into correcting this issue.

BaseCamp data from the GPSMAP 66s Overall route from the GPSMAP 66s using BaseCamp software

Our opinion

Overall, I was pleasantly surprised by the Garmin GPSMAP 66s. It exceeded my expectations in terms of usability and usefulness. While there is certainly a slight intimidation factor involved when first using the device, it does not take long for those fears to dissipate and in a short space of time, it can become an incredibly helpful tool for navigating and recording.

Based on my experiences, I would suggest that the GPSMAP 66s would be suitable for ecological work in open spaces where there is a need to recording transect routes or coordinates. However, care should be taken when using the GPS to mark precise coordinates as the unit is only accurate to around 2 to 5 meters in good conditions and features such as tall buildings, steep valleys, harsh weather and dense tree cover can reduce this accuracy.

I would recommend the TOPO Pro Bundle option as the more detailed OS maps are a massive step up from the basic maps that come with all Garmin GPS devices.


The GPSMAP 66s can be found here. Our full range of handheld GPS devices can be found here.

If you have any questions about our range or would like some advice on the right product for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

 

NHBS In the Field – Rigid 20w Skóros Moth Trap

Recently added to our range, the Rigid 20w Skóros Moth Trap is a lightweight portable moth trap, comparable to the successful Heath moth trap in design. Featuring a compact, rigid base that requires no preassembly, Skóros (from the Greek word for moth) is ideal for children, beginners or the seasoned lepidopterist looking for a portable, no-fuss trap.

We tested the Skóros in a small, suburban garden towards the end of the peak-trapping season in late August.

Use in the field

The first thing I was struck by while setting up the trap is how robust it feels. Despite weighing a mere 1.7kg, all the plastic parts are sturdy and indicate the trap could withstand many years of use. It’s relatively small in size when compared to Skinner moth trap designs, for example, making storage and transport easy.

The supplied 20w bulb is bright enough to have a successful attraction rate while not being overly intrusive to any immediate neighbours.

As previously mentioned, the rigid base requires no preassembly so set up is a straightforward affair; simply slot the three plastic vanes into the cone and place the lid on top. Finally, screw the supplied bulb into its fitting, taking care to handle it by its base rather than the fragile glass envelope. Remember to place egg boxes on the base underneath the cone so that any moths that fly into the trap have somewhere dry and dark to settle until they are released the next morning.

Checking the weather for favourable trapping conditions (preferably a calm, warm and dry night), the trap was deployed on a muggy, overcast August evening around dusk. This timing increases the chances of catching some of the crepuscular or day-flying species.

We left the trap tucked in the corner of the garden, taking advantage of the white garden wall to reflect some of the light and the 5m mains cable was suitably long enough to run alongside the wall through a nearby open window to be plugged in. The Skóros was left running from just before dusk to a little after sunrise.

What we found

Returning to the trap early in the morning we were greeted with a decent sized catch, perhaps smaller than some of the larger-based traps in our range but still enough to keep us busy examining and ID’ing for an hour or two!

Accessing the catch itself is also very straightforward; the plastic cone pops easily out of the base, allowing easy access to the egg boxes laid down the night before.

Many of the moths caught were starting to look a little ragged, but using a copy of Field Guide to the Moths of Great Britain and Ireland and some magnifying pots for the smaller micro-moths, we recorded the following list of species:

  • Knot grass (Acronicta rumicis)
    Purple bar (Cosmorhoe ocellata)
    • Brimstone
    • Lesser broad-bordered yellow underwing
    • Bird cherry ermine
    • Lime speck pug
    • Blood vein
    • Large yellow underwing
    • Flame shoulder
    • Square-spot rustic
    • Purple bar
    • Vines rustic
    • Mullein wave
    • Small square spot
    • Common carpet
    • Double-striped pug
    • Pale mottled willow
    • Several hard-to-definitively-ID micro-moths!

     

    Brimstone moth (Opisthograptis luteolata) and mullein wave (Scopula marginepunctata)

    It’s also worth noting several species perched themselves on the walls and foliage around the trap, so we would recommend searching the immediate area surrounding the trap where it has been running overnight.

    Our opinion

    The Skóros strikes a good balance between portability and affordability. Its no-fuss assembly, compact size and affordable price point makes it an ideal first moth trap for beginners or children.

    I did feel that the cylindrical base meant that there was less floor space on which to place egg boxes than some of the rectangular Heath traps, but considering the relatively small urban garden the trap was deployed in, it had a respectable catch and retention rate and the slight disadvantage of small floor space is easily offset by its ease-of-use and ergonomic design.


    The Rigid 20W Skóros Moth Trap can be found here. Our full range of moth traps can be found here.

    If you have any questions about our range or would like some advice on the right product for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

     

NHBS In the Field – EasyLog USB Temperature and Humidity Logger with LCD Screen

The Easylog USB Temperature and Humidity Logger with LCD Screen (EL-USB-2-LCD) from Lascar electronics is a great addition to any field kit bag. This is one of the most popular models in the EasyLog range, offering a very high degree of accuracy for its recordings, measuring a range from -35°C to + 80°C, plus a humidity range from 0 to 100% RH.

What’s in the box

The EL-USB-2-LCD is packaged inside a static shielding bag and comes with a translucent plastic cover to protect the USB stick. A quick start guide is included with clear step-by-step instructions on set up, replacing the battery and a mini-guide to the different LED flash alarms.

Setting up

The first step in preparing to use your EL-USB logger is to download the EasyLogUSB software from the website here.

The software is free to download and is compatible with 32 bit and 64-bit versions of Windows 7, 8 and 10. Please note that the software is not compatible with Apple or other devices not specified.

Once installed you will need to insert the logger into a USB port and click the Setup and Start USB data logger which will take you through a series of steps to calibrate and personalise your logger, ready for use. This will give you the opportunity to set the parameters of the logger to your requirements.

Some of the features of the logger that can be customised include:

  • Logger name
  •  °C / °F
  • Logging rate (10s, 1m, 5m, 30m, 1hr, 6hr, 12hr)
  • High and low alarms
  • Immediate, delayed, and push-to-start logging
  • Display off, on for 30 seconds after button press, or permanently on
  • Data rollover (allows unlimited logger by overwriting the oldest data when memory is full)

Once the setup is complete, you will receive a confirmation message and the logger should then be removed from the USB port, to preserve its battery life and cool down before use. It is now ready to go.

Use in the field

We tested the logger on the banks of the River Dart in south Devon in early August 2021. We set the logger to record every 10 seconds and monitored the site from mid-morning to early afternoon.

When using the logger, always keep the clear plastic cap on to protect it from the elements. When ready, start the recordings using the single button.

This button can be used to navigate between settings, although we found it rather stiff, requiring a firm push for activation. The LCD screen then displays the live temperature or humidity reading (you can switch between the two) and previous maximum and minimum readings for both too. The little LED for both will also flash to indicate when recording is in progress and will alert you to any temperature or humidity alarms, if reached, too.

In many circumstances, where the logger is being used to record temperature or humidity at a static field site, it can be attached to a tree, cane or post via a cable tie or tape, or placed in a secure location. Alternatively, it can be simply carried or clipped onto a belt/lanyard if needing to accompany a surveyor along a route.

We found the accuracy of the readings superb and far more sensitive than those that might be produced by, for example, a phone. The device is small, lightweight, and easy to navigate, so is ideal for taking out into remote or inaccessible locations. It can be equally as helpful for constant monitoring, for instance when checking incubators, animal habitats and enclosures, or even a room or fridge. With an impressive battery life lasting up to two years and the capacity to store 16,000 temperature and humidity readings, it’s a particularly versatile logger, suitable for many circumstances.

The EL-USB-2-LCD is also one of the EasyLog’s most robust models with a sturdy casing that has been tested to IP67 standards. And so, when the protective cap is correctly fitted, it has excellent protection against water and dust.

Software

Once you have collected your readings, insert the logger back into a USB port and click the Stop USB Data Logger and Download Data. The data will then be transferred to your computer and can then be viewed. The display will first default to show your temperature, humidity, and dew point readings all in an axis graph.

Here is an example we produced from our readings:

Below is a key to the graph information.

  1. Vertical axis, including scale and unit
  2. Horizontal axis, including time-related information
  3. Data logger name
  4. Low alarm trigger level, a horizontal dashed line
  5. High alarm trigger level, a horizontal dashed line
  6. Plotted data line
  7. Marker line that follows the mouse pointer
  8. Marker line data for the current marker line position, or the logging period if no marker line is shown

Within the top toolbar, there is the option to save, export, zoom in and out, and switch from a graph to a data view. Under the view tab, you can also sort and organise your data under very useful different parameters that include data range, gridlines, mark samples, statistics, and data view.

Each of these tools can help further filter or analyse your results. Then using the Export function, you can easily produce and extract professional reports saved as either CSV data files, JPEG images, a PDF document of the data, a graph summary, or an Excel spreadsheet.

We found that extracting specific information from the data was quick and straightforward with these functions. The toolbar is kept simple so that the display does not appear cluttered with too many options and functions. Overall, the software is very intuitive to navigate.

Summary

Although there is now a wide range of temperature and humidity loggers available to choose from, the outstanding accuracy of this model, alongside its customisable features and tough weather-proofing makes the EL-USB-2-LCD a standout choice.

The EasyLog range starts with the entry-level EasyLog Mini USB, which is limited to only recording temperature and at 30-minute intervals. At the top end of the range is the EasyLog Professional Data Logger which covers the greatest temperature ranges, offers the longest battery life (3 years), recording capacity (32,000) and the most flexible parameter settings, including the option to record every second.

We find the EL-USB-2-LCD to be the best ‘all-rounder’ within the range, covering both humidity and dew, as well as a wide range of temperature recordings, all at an affordable price. We also feel it has an advantage over the similar EasyLog USB Temperature and Humidity Logger. For a relatively small increase in price, we found the LCD screen a particularly useful addition when out in the field, as we could check the live temperature or humidity before starting a survey or prolonged recording session. This screen also reassures you that your logger is working correctly, which is valuable if taking the logger out to a remote location, for example.

Users can rest assured knowing that their readings will be highly accurate and that their data can be also quickly converted into effective reports through the excellent software.

Overall, we found the EL-USB-2-LCD superb and would recommend this model for its versatility, accuracy and fantastic settings that should cover most needs and circumstances.


The EL-USB-2-LCD can be found here. Our full range of EasyLog products can be found here.

If you have any questions about our range or would like some advice on the right product for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

 

NHBS In the Field – The Anabat Scout product review

Here we review the Anabat Scout from Titley Scientific. The Scout is an easy to use active bat detector that offers excellent quality live audio and recording, plus many handy surveying features and durability that sets it apart from other detectors. It uses heterodyne, auto-heterodyne and frequency division audio that can be recorded in either full spectrum or zero crossing files.

Designed with professional surveyors as well as the more serious bat enthusiast in mind, the Scout is an ideal detector to take on bat emergence and transect surveys. This is thanks to great features such as a bat counter and GPS tracking transect mode.

How we tested

In early July 2021, we tested the Scout outside an old barn in South Devon to monitor the dusk emergence of several bat species. The building was known to host many common pipistrelles, brown long-eared, lesser horseshoes and some myotis species. We wanted to see how easy the detector was to use in the setting of a busy emergence and get a feel for its recording quality and its special features. The audio was set to auto-heterodyne to see how good this feature would be with multiple bats close by. Under the trigger settings is the option to adjust the sensitivity, which we set to high as there was unlikely to be too much undesired noise in this setting.

What we found

Firstly, it is worth noting just how lightweight (at 160 grams without batteries) and easy to hold the Scout is with its handy wrist lanyard and comfortable fit within your hand. These features are particularly important when undertaking long surveys and holding other equipment such as a clipboard for instance.

The OLED display screen is small, but bright, so key information such as peak frequency and time is easy to note in the dark. With just key information visible, the screen does not become too “busy” unlike some detectors, which in some circumstances is a real advantage as it avoids too much distraction. The buttons all glow in the dark, which we found very useful once it had become completely dark, as it kept navigation simple, without having to use a torch.

One of the Scout’s most handy features are the in/out bat counter buttons which enable you to easily tally the number of bats recorded coming out and back into a roost, without the need to look away to make notes and perhaps miss bats. The counter also time and date stamps and geotags each count (CSV file output), so saves you having to manually note this data.

The Scout has a transect mode which notes a GPS coordinate every second so maps out your route as you walk it. It also logs another GPS coordinate for every bat recording made which produces detailed transect maps.

We found that the adjustable volume control was very good and loud enough when needing to compensate for background noises such as a passing lorry.

Also noteworthy was the Scout’s ability to record voice notes. Once it has become fully dark or if you are surveying and need to keep your eyes fixed on bat watching, then the ease of just speaking into the device to add survey notes or further information is very helpful.

The Scout was very productive at picking up all the bats we encountered during the evening (although sometimes a brown long-eared emerged without calling and was missed). The auto-heterodyne tuning to the peak frequency was superb and saved much time. On a few occasions, we switched to manual heterodyne which enables you to adjust the frequency by moving the up and down arrows. This setting would be useful when first teaching beginners. The Scout’s range is also excellent, which was demonstrated when a high flying noctule was picked up probably over 30 – 40 meters away.

Two recordings taken on the Anabat Scout and visualised through the Anabat Insight Software.

The recordings were always clear through the built-in speaker, although there is also the option to attach a 3.5mm headphone jack. All recordings come with GPX track files attached. This gives accurate GPS data, that when viewed on the free software: Anabat Insight, a .KML (Keyhole Markup Language) file can be generated using Google Earth which will show your route with location tags for each bat recording.

All recordings were stored on an SD Card (recommended min: 32GB and max 512GB) and then output via WAV (Full spectrum) and Anabat sequence files (Zero Crossing).

Battery life lasted roughly 10 hours on 2 x AA (NiMh, Alkaline or Lithium) batteries with the remaining memory space and battery life displayed on screen, so we could keep a check during the evening.

Our Opinion

The Anabat Scout is certainly one of the easier to use, professional bat detectors available. It is highly accurate with its triggers and by being so lightweight and practical it makes for an ideal choice for both ecological surveyors and keen naturalists alike. The Scout has been designed with the needs of surveyors in mind and even those new to bat detecting, will find it simple to use and highly rewarding.

The main limitation found was that the Scout does not display full spectrograms like the Anabat Walkabout, therefore beginners particularly, may not find this detector so helpful for learning the differences in calls and identification in the field.

Overall, we feel the Scout offers very good value as an active detector that will fulfill the needs of most ecological surveyors. Its advantage of being incredibly easy to use and get to know, makes it fantastic for beginners, subcontractors and educational purposes also.


The Anabat Scout can be found here. Our full range of active bat detectors can be found here.

If you have any questions about our range or would like some advice on the right product for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

 

Newly released trail cameras in 2021

Trail camera technology is rapidly advancing and quickly becoming more affordable, allowing anyone to view the wildlife visiting their gardens. During the first half of this year, we have had four new models released on our website boasting updated and improved specifications.

Browning and Bushnell are renowned trail camera brands used by researchers, conservationists and amateur naturalists around the world. Both brands offer high-quality, durable units at a range of price-points.

2021 has brought three new models of Browning camera, named the ‘Elites’. All three are continuations of previous series. The Recon Force and Spec Ops Elite HP4 are similar to the older ‘Edge’ models. The principal change is the addition of high power LEDs which have increased the night time range and image quality. The two cameras are essentially the same design, however the Spec Ops offers no-glow flash rather than the Recon Force’s low-glow.

Browning Recon Force Elite HP4

 

• High power LEDs
• 22MP images, 1920 x 1080 HD video (60 frames per second)
• 0.1s – 0.7s adjustable trigger speed
• Low-glow infrared flash
• 5cm colour viewing screen

 

Browning Spec Ops Elite HP4

 

• High power LEDs
• 22MP images, 1920 x 1080 HD video (60 frames per second)
• 0.1s – 0.7s adjustable trigger speed
• No-glow infrared flash
• 5cm colour viewing screen

 

Browning Command Ops Elite

The Command Ops Pro, Browning’s entry level camera, has been replaced by the Command Ops Elite. Despite coming in at a lower price point than other cameras in the range it boasts some fantastic features, including a faster trigger speed than its predecessor. If a colour viewing screen is not an essential feature for you, this camera will allow you to take images and videos at a significantly more affordable price.

 

• 18MP images, 1280 x 720 HD video (30 frames per second)
• 0.3s trigger speed
• Low-glow infrared flash
• Black and green text screen

 

 

Bushnell Prime

Similarly, Bushnell released a new entry-level camera this year. The Prime offers a similar spec to the Command ops, but with significantly higher megapixel images. For more information on this camera and to see it in action, please read our ‘In the Field’ blog post.

 

• 24MP images, 1280 x 720 HD video
• 0.3s trigger speed
• Low-glow infrared flash
• Black and white text screen

 

 


Explore the complete range of trail cameras on our website or take a look at our Watching Wildlife guide on how to choose the right trail camera.

Watching Wildlife – How to choose the right Trail Camera

This is part one of a two-part series that will look into different ways of filming wildlife in your back garden. In this part, we will take a look at trail cameras and what to look out for when buying one. 


The variety of trail cameras on offer can be overwhelming, here are a few key things to look out for:

Type of LEDs

In order to capture videos or images in the dark, camera traps use infrared LEDs to illuminate the subject with little to no visible light used. There are two main types of LED flash systems that trail cameras use. These are No Glow and Low Glow. No Glow LEDs produce very little visible light and so are almost completely undetectable by the subject. Low Glow LEDs produce a faint red glow and so are not completely invisible, which can sometimes alert animals such as deer and foxes. However, they do have the benefit of being able to illuminate better over a longer distance.

Red Fox Bushnell Trail Camera
Red Fox captured on Bushnell Trail Camera
Trigger Speed

Trigger speed is the time taken for the camera to take a photo once it has detected movement. If you are aiming to capture a fast-moving subject, then a quicker trigger speed (below 0.3 seconds) will enable you to achieve these photos before your subject has moved out of frame. 

Recovery Time

Recovery time is the time taken for the camera to process an image and become ready to take a second photo. If you want to capture multiple images of a subject as it comes into view of your camera, then a shorter recovery time will allow for this.

Badger photo Ltl Acorn Trail Camera
Badger photo captured on Ltl Acorn Trail Camera  ©Bryony James
Hybrid Mode

Hybrid mode allows the camera to take videos and photos simultaneously. A camera with this capability may be useful if you want to get as much footage as possible of anything that falls into frame of the camera. If you are more interested in capturing only photographs or only videos, this mode may not be an important feature.

Resolution and Interpolation

The quality of the images and videos that your trail camera can take will depend on its resolution. Most cameras have settings that can alter the resolution either, decreasing it through compression, or increasing it through interpolation. Compression is useful if you want to deploy your camera for a long time and memory card capacity may become an issue, whereas interpolation can produce a larger image by adding pixels. The best way to compare the quality of images between cameras is to look at sample photos and videos. The displayed megapixel value is often resolution as a result of interpolation. The true resolution of the image sensor can usually be found in the specifications as the true sensor resolution.

Screen

Many trail cameras come with built-in viewing screens allowing you to view your photos and videos in the field. This is particularly useful if you want to take a few test shots to check the positioning of the camera.

Our Suggestions

Browning Strike Force Full HD

If you’re looking for a good entry-level camera, then take a look at the Browning Strike Force Full HD. It takes high quality images and videos for a very affordable price.
LED type: Low Glow
Trigger speed: 0.135-0.7s
Recovery time:  0.5s
Hybrid: No
Resolution: 22MP
Viewing Screen: Small screen showing text only

 

Browning Dark Ops HD Pro X

For the next step up, the mid-range  Browning Dark Ops HD Pro X is one of our most popular trail cameras. With No Glow LEDs and a impressively quick trigger speed, this is a great all-round option.
LED type: No Glow
Trigger speed: 0.22s
Recovery time: 0.6s
Hybrid: No
Resolution: 20MP
Viewing Screen: 3.8cm colour screen

 

Bushnell Core DS No Glow

If the hybrid mode is an important feature for your work, a Bushnell Core DS No Glow may be the one for you. Dual sensors target day and night in order to provide the best quality images, no matter the light conditions.
LED type: No Glow
Trigger speed: 0.2s
Recovery time: 0.7s
Hybrid: Yes
Resolution: 30MP
Viewing Screen: 5.08cm colour screen

 

Browning Spec Ops Elite HP5

If the subject of your trail camera photos or videos is particularly fast, it may be worth taking a look at the Browning Spec Ops Elite HP5 whose adjustable trigger speed starts from 0.1 seconds is one of the fastest on the market.
LED type: No Glow
Trigger speed: 0.1-0.7s
Recovery time: 0.5s
Hybrid: No
Resolution: 24MP
Viewing Screen: 5cm colour screen

Accessories

There are a selection of accessories that you may want pair with your camera to get the best out of your camera-trapping experience.
If you are worried about leaving an expensive piece of kit outside and unattended, then you may want to invest in a Python Lock. This cable lock will fit most trail cameras and and will give you piece of mind that your camera is secured in place. Here you can watch how to set up this lock with your own trail camera. You also may be interested in a security case that is compatible with your trail camera. These cases house your camera and secure with a padlock, which helps prevent vandalism and theft.

SD Cards

All cameras need a memory card to store your photos and videos on. Make sure to check what SD card capacity your camera needs, this is usually found in the specifications section. Browse our selection of SD cards to order alongside your camera so that you can get snapping as soon as possible.

Power Options

Most cameras are powered by batteries. We recommend you use Lithium Ion batteries with your trail camera to ensure maximum trigger speeds and longer battery life. Make sure to check how many batteries your camera needs. Some trail cameras are also compatible with solar panels which will allow you to extend the battery life of your camera. This is especially useful if you want to leave your camera outside for extended periods of time.

Starter Bundles
Browning Strike Force Starter Bundle

If you are looking to buy a trail camera and want to make sure you will be able to get out and start capturing as soon as it arrives, then you may want to take a look at our starter bundle options. These bundles come with a memory card and batteries that are right for your camera to ensure you have everything you need to get started.

To see more trail cameras available, take a look at our range here

Would you like some more advice on which trail camera or nest box camera is most suitable for you? Contact us on +44 (0)1803 865913 or email customer.services@nhbs.com . 

NHBS In the Field – H2a Hydrophone

The H2a hydrophone from Aquarian Audio is a mid-range hydrophone, allowing high quality recordings for professionals, whilst remaining affordable for marine naturalists.

Like most hydrophones, the H2a is powered via a compatible recording device. Available with either a TRS 3.5mm jack (plug-in power required), or XLR connector (phantom power required) and a variety of cable lengths, you are sure to find an option suitable for your requirements.

How We Tested

We tested the H2a hydrophone across two days in varying weather conditions in early June 2021.

Our kit was made up of the 3.5mm jack H2a hydrophone, in conjunction with an old DR-05 Tascam recorder and a pair of earphones. The DR-05 is actually a discontinued model, however we do sell it’s successor, the updated DR-05X. The H2a will work well with any recorder with a 3.5mm port that can provide plug-in power. Many recorders offer this ability, but if you are unsure please do check your manual.

Setting up the hydrophone system was very straightforward. Once plug-in power was switched on via the recorder’s menu settings, we simply plugged in the H2a to the mic-in socket and were ready to begin.

Tests were performed in a number of environments including rockpools, off a small boat in deeper water and a controlled environment (container of water). Between these locations, we did find adjusting the gain accordingly was necessary, however this was straightforward, using the Tascam recorder’s input level controls.

In shallower, more disturbed water we tried attaching the cable to a makeshift ‘boom pole’ aiming to gain greater control over the movement of the hydrophone while reducing handling noise.

It is built to be durable, with a stainless steel core and rubber covering, but we still handled it with care and rinsed and dried it after each use. Aquarian themselves say the H2a can survive accidental drops, however we chose not to test this!

Recordings were made on the Tascam device, to a micro-SD card and then transferred to a computer. The open-source audio program Audacity was used to view the waveform, including adjusting levels, and also allowed us to plot the frequency spectrum.

What we found

Our initial impression was that the H2a was surprisingly lightweight and compact, measuring just 25mm x 46mm (without the cable) and weighing little over a hundred grams. This made for easy packing in a small rucksack.

The hydrophone comes in neat cardboard packaging which is not particularly suitable for use on location. Despite the hardiness of the hydrophone itself, it would certainly provide peace of mind to purchase or use some form of carry case. We would not, however, recommend a waterproof case as it may trap moisture and salts that could eventually lead to corrosion.

The hydrophone is highly sensitive and so was vulnerable to signal overload if knocked accidentally or handled roughly. During recording, our main obstacle was noise from cable handling, which was noticeable during playback. This is to be expected with any hydrophone and certainly was not the worst I have experienced, but was still slightly frustrating. We quickly learned to ensure the cable was lowered ‘hand over hand’ into deep water to minimise noise.

Even with only a 3 metre cable, slight tangling did occur, which over time could lead to damage. For future uses with longer cables we would consider investing in or making a cable spool/reel. A spool would likely also reduce the experienced cable handling noise.

In shallower water, especially along the tide line, the makeshift pole attachment was very successful and made a significant difference to cable noise level. It also allowed us to position the hydrophone with precision and avoid damage that could have occured from the stronger waves dragging it towards nearby rocks.

When working from the boat in deeper water, we simply released the cable by hand as the current was slow. We found the shape and weighting (high specific gravity) to be a clever design that kept the hydrophone more-or-less vertical even in currents. Although it is worth noting that we only tested this ourselves in relatively slow moving water.

Below is a sequence of recordings taken in varying locations. The first exhibits the sound produced by the paddling of the small boat. The hydrophone performed very well while being dragged behind the boat, catching the bubbling as the paddles broke the surface.

Of particular interest to us in the field was the man-made noise pollution from the nearby (0.5 miles away) docks. Despite being rather un-noticeable by air, loud hammering was clear through the hydrophone.

The final recording in the audio above was taken at a rising tide, with gentle waves shifting the sand and sediment below the hydrophone.

While we had heard reports that some people have found sensitivity dropping off at higher frequencies with this unit and other hydrophones, our field tests produced recorded sounds up to 10kHz easily.

Our Opinion

Clear audio with limited unwanted noise was easily produced with the H2a hydrophone. It provides a fantastic way for ocean lovers and scientists alike to explore life underwater.

A few practical accessories such as a pole and spool would be worth considering as they can really improve audio quality while also making work in the field just that little bit simpler.

With further experimentation and potentially a bit of luck with interesting sound sources, I am confident that the H2a will continue to yield high quality recordings at a very fair price point.


The H2a hydrophone is available from the NHBS website on its own or as part of a kit including the Tascam DR-05X recorder.

Note: When deciding upon a model it is recommended to choose based first and foremost on compatibility with your recorder’s connector type. XLR is however, often the preferred choice for professionals due in part to reduced electromagnetic interference.

Visit nhbs.com to view our full range of hydrophones. If you have any questions about our range or would like some advice on the right product for you, then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

 

An Evening at Sharpham – Bat and insect survey

The lengthening evenings of late Spring or early Summer are an ideal time for an evening wildlife walk. Now the vegetation has become more lush and the air has become warmer, the insects form in thicker clouds and the bats are now on the wing.

The Sharpham estate is a 550-acre area which runs alongside the River Dart just outside Totnes. This historic landscape is home to the Sharpham Trust, an educational charity whose Wild for People project aims to rewild areas of the estate and enhance biodiversity in the region. To read more about the history of the Sharpham Estate and the launch of their Wild for People project, click here.

A few of us from NHBS walked up to the Sharpham estate where we met a group of Ambios’s conservation volunteers and trainees for an evening wildlife walk. We brought a selection of bat detectors with us and explained the differences between our most popular professional detectors. We distributed any active bat detectors among the volunteers and showed them how each type worked. We then left the farm just as dusk was settling with detectors armed and ready.

As we wandered the footpaths and fields of the estate, we watched several Noctule and Leisler’s bats commute high above the fields, along with some Common and Soprano pipistrelles zipping along the hedgeline foraging.

We then cut across a field to a dead tree where NHBS Wildlife Equipment Specialist Josh had previously set some insect bait traps. The traps were baited with a mix of banana and beer and had been set in the hopes of catching saproxylic beetles emerging from dead wood.

Josh has also been monitoring the beetle diversity of Sharpham through a series of pitfall traps placed across the estate, although prior to our walk they had unfortunately been closed due to heavy rain. Unfortunately no beetles were found in the traps this time, but we did spot a variety of species scurrying along the field and forest paths including Anchomenus dorsalis, Dromius agilis and Staphylinus dimidiaticornis, along with the very common Nebria brevicollis (gazelle beetle) and Pterostichus madidus (black clock beetle).

Once it was much darker, on our way back up to the farm, we also had the pleasure of listening to the alien-like call of a sitting Lesser Horseshoe bat that was perched just meters away from the group. It made for an exciting end to the walk and we hope to detect even more bat species through passive detector recordings.


See the full range of bat detectors and insect survey equipment on the NHBS website.

To find out more about Ambios and the work of Lower Sharpham Farm, please visit https://www.ambios.net/.