Monday, April 20, 2020

Experiments with flash duffusers, Part 2


Canon MT24-EX twin macro flash
One of the ways to ameliorate the harsh lighting from a single flash gun is to use two flashes so that one fills in the shadow caused by the other The Canon MT24-EX puts the two flash heads close to the subject on a cunning mounting ring and, consequently, allows for a small aperture at reasonable ISO. I have not been able to find figures for the flash duration, but the power can be adjusted from full to 1/64th.

Here is the same target I used for the previous article shot with my MT24EX. Again I used the Canon EOS R with a Canon 100mm F2.8L macro in manual focus mode with the focus set to 1:1. The exposure was F16 at 200 ISO with the shutter speed set to 1/200s (the fastest flash sync speed for the camera). The flash was set to manual mode and the exposure bracketed by setting the power in steps between 1/4 and 1/32 power.
MT24EX at 1/16 power

Compared with a single flash, the shadows are much reduced, but the specular highlights are very obvious - although there are now two, one on either side of the thorax of the Syrphus as well as the strong reflections from the wings. My feeling is that, compared to the YN560, this flash produces slightly warmer colours.

Just like the YN560 in the previous article, various plastic "diffusers" are available. These two were designed for the popup flashes on the top of cameras. I bought them a long time ago at a photo show (they were quite expensive!) because they happen to fit the MT24EX's flash heads reasonably well. The attachment is somewhat precarious and one of the arms got broken at some stage. It is held on now by the inevitable duct tape!
Here are the test target results:
MT24EX with plastic diffusers, 1/8 power
Rather like the YN560's plastic cap, these plastic "diffusers" make very little difference. They absorb or scatter some light, so the exposure requires about a stop more light but, because the size of the flash heads has not changed, the quality of the lighting hasn't really altered. The specular highlights on the thorax and wings are pretty much unmodified.

To achieve more diffuse illumination requires some way of spreading out the area from which the light is coming. Some time ago, I had the idea of using a polystyrene bowl in front of the flash heads to spread the light and I actually bought a set of disposable party bowls from Tesco to try this out. But, how to attach it in front of the flash heads? The inspiration came from noticing that the MT24EX mounting ring has a 58mm filter thread. So, I thought of some sort of filter mount or stepping ring that would screw into this thread. Whilst searching for something suitable on eBay, I came across a low profile lens hood which has three slots in the sides for just £4.95. I thought I could cut between these slots to leave just the base, but this turned out not to be necessary - the hood is low profile and does not get in the way at all and so could be used as is.

The external diameter of the hood is 61mm, so I cut a hole in the base of a bowl of this size. The thin polystyrene is tricky to cut, either using scissors or a craft knife. It has a tendency to splits. Wrapping the edges with thin strips of duct tape strengthened it and stopped the cracks spreading. It is also necessary to cut the lower side of the bowl flat so that it doesn't get in the way if you are trying to get low to the ground. Again, the cut needed reinforcing with narrow strips of duct tape. For my first attempt, I also cut off the rim of the bowl, but this turned out to be a mistake. Without it, the bowl became too weak and floppy.
MT24EX with polystyrene bowl diffuser fitted.
An alternative would be to try expanded polystyrene bowls, which are probably a bit more rigid and certainly easier to cut accurately and cleanly. But I suspect that the light loss would be considerably greater since they are thicker, but probably worth the experiment. Anyway, here are the results shot using the bowl diffuser:
MT24EX with bowl diffuser, 1/4 power
This has somewhat toned down the specular highlights and filled in the shadows and produced quite a pleasing image. I don't think this material has caused a noticeable colour shift. Possibly, the colours are a fraction warmer.

One of the advantages of the MT24EX is that it is very practical and convenient to use. The whole thing fits together easily and securely and it lacks the bulk of a setup based on a bigger flash gun like the YN560. The heads can be moved around the mounting ring and tilted up and down, so that it is very versatile, and the ratio of power between left and right can be adjusted to vary the modelling. The bowl diffuser also fits quite securely, doesn't get in the way or badly interrupt the view when trying to home in on a subject. I have found it to be a good setup in the field. Here are some examples taken in the garden using it.
Solitary bee Osmia bicornis

Beefly Bombylius major

Hoverfly Platycheirus scutatus - male

Sunday, April 19, 2020

Experiments with flash duffusers


Electronic flash is ideal for macro photography. The flash duration is very short, meaning that any subject and camera movement should be frozen. This article gives measurements of the duration for a YN560. For example, at 1/2 power, the duration was 1/1359s and at 1/4 power, 1/2809s. At the same time, by placing a bright source of light close to the subject, it allows a small aperture at reasonable ISO to be used. When photographing subjects at reproduction ratios close to 1:1, depth of field is critical, so I like to keep the aperture at around F16.

The downside of electronic flash is that it can give very harsh lighting. This results from the relatively small size of the flash tube with respect to the subject distance which makes the lights highly directional. The light falling on the illuminated side contrasts strongly with dark shadows on the other side. Diffusing the flash in some way ameliorates this and aims to provide softer, less directional and contrasty lighting. A search on Google comes up with loads of ideas for both DIY and commercial solutions. So, I decided to try out some of the ideas with the sorts of subjects I like to photograph. There are two factors to consider here: firstly, achieving attractive lighting, but secondly, the setup has got to be practical when taking photos of wild insects in the field.


I set up a target consisting of a couple of freshly caught flies from the garden - a male hoverfly, Syrphus ribesii, and a Muscid, Phaonia tuguriorum, pinned through a fresh leaf to provide a typical background. Then an X-Rite Colour Checker Classic colour card was positioned so that the bottom left three squares are visible above the flies. These are three very pale grey panels which I will use to adjust the white balance during RAW processing so we can assess the effect various diffusers are having on the colour of the flash.


All the shots were taken with my Canon EOS R in manual mode with a 100mm F2,8L Canon macro lens set to manual focus at 1:1. The aperture was set to F16 and the ISO to 200. I bracketed the exposures for each shot by adjusting the flash power up and down and chose the shot where I could discern the three shades of grey from the colour checker. The shutter speed was set to 1/200s - the fastest flash sync speed for this camera. On the whole, these chosen shots where the lightest of the three grey panels was not blown, looked somewhat underexposed to me, so I also cropped out the Syrphus and increased its exposure (in RAW processing) by 2/3 of a stop. I will present the whole image (reduced in size) and the crop (reduced to 1300x3000 pixels).

Yongnuo YN560 IV

Yongnuo 560 IV flash and RF605C wireless trigger
The flash head tilts up, but not downwards, so sitting it in the hot shoe on top of the camera, it won't depress enough to direct it at the focus point at 1:1. It would probably still work, providing it was set near its wide angle beam focus setting, but that would waste a lot of the light. So I mounted the slash beside the camera using a flash bracket and a small ball and socket.

This allows the flash head to be aimed and positioned closer to the focus point. However, there needs to be a way to trigger the flash. For this I used a Yongnuo RF605C wireless trigger on the camera's hot shoe.

YN560 at 1/16 power
As expected, the lighting is quite harsh with a strong shadow and strong specular highlights on the thorax and wing tips of the Syrphus.

If you search for 'flash diffuser' on Google, one of the things you will find in quantity is plastic caps to fit over the flash-head. I got one of these free with one of my Yongnuo guns.
The sort of "diffusers" are pretty useless! The textured plastic will scatter the light and therefore reduce the amount of light reaching the subject. But the size of the light source hasn't changed, so the directionality is the same and will result in very little change to the harsh contrast between the lit side and the shadow.

YN560 with plastic cap at 1/8 power
Comparing these images with the previous set, we can see that, as expected, the plastic cap "diffuser" has made very little difference, although it cut the light by around a stop. The shadows and the specular highlights on the Syrphus and pretty much unchanged. I do think that the plastic has affected the colour balance a bit - giving a slightly warmer image.

To actually achieve decent diffusion of the light, it is necessary for the light source to be much larger so that light rays reach the subject from many different angles. One way to do this is to build some sort of funnel shaped structure  with the flash gun at the narrow end and a panel of translucent diffuser material at the wide end. Here is an example on YouTube by Reinhard Biller. I actually built something like this a long time ago for my Olympus T32 flash that I used with my Olymput OM2 macro gear. I refitted it for the YN560 just by modifying the size of the neck that fits round the flash head. It is made of cardboard lines with aluminium foil and the diffusing sheet on the front in tracing paper.
This will fit in the camera's hot-shoe because it was designed to point downwards.
YN560 with cardboard diffuser, 1/4 power
This time the light has been diffused substantially, the shadows are much softer and the specular highlights have also been toned down significantly. Altogether a more appealing image.Again, I think the colours are a little warmer than the raw flash. We have lost about 2 stops compared to the raw flash. Whilst the results are good, this is not a very practical device as it stands. It is rather fragile and would be ruined if it got wet. This could be tackled by using different material, e.g. foam core board and stronger joints, e.g. stuck using a hot glue gun. However, it is rather bulky and unwieldy, although not heavy, and would be difficult to manoeuvre amongst vegetation.

Another idea is to attach the diffuser around the end of the lens and illuminate it using a flash mounted on the hot-shoe without anything in between. I quite like this example, which is very easy to make. I tried this out, but found itr to be quite impractical for insects in the field. Firstly, it projects some way in front of the lens and tends to hit the vegetation the insect is sitting on and so disturbs it. Secondly, it blocks the view of the area you are trying to move in on and so makes it rather hard to find the subject. When you are working around 1:1, nothing comes into focus in the view finder until you are very close. So it is essential to be able to see where you are going and before you start looking through the view finder - which will be at the last minute.

Another idea is some sort of bounce card attached to the flash gun which is pointed more or less upwards and the light then bounces off a surface tilted at 45 degrees something like this example. There is no reason why this can't be combined with a diffuser screen placed in front of the reflector. I made the reflector part from the plastic cover of a file folder with aluminium foil stuck to the front. On the back, I attached a couple of pieces of soft wire with duct tape so that it can be positioned and will hold its shape. It is attached to the flash gun with a couple of wide rubber bands. The diffusing sheet on the front is garden fleece.

Mounted on the flash bracket, it can be positioned close to the subject.

Here are the results:

YN560 with DIY diffuser, 1/2 power
This has produced a good degree of diffusion, although it is obvious that the flash is placed to one side (to the right), so that there is some shadow on the left. The specular highlights on the thorax and wing are nicely softened. The garden fleece seems to provided a good, neutral diffuser. I cannot remember where I saw the tip about using this material as a diffuser, but it seems a pretty good idea, especially as you can easily add more layers to increase the amount of diffusion (there are 4 layers here). The combination of the bounce and the diffusion os taking 3 stops compared to the raw flash. This turned out to be a fairly practical design. The front of the diffuser remains behind the lens, so it doesn't interfere with the vegetation or get in the way of the view. The main problem was being aware of the shade it casts. Hoverflies and other insects are rather sensitive to being shaded and will often go if the shadow of you or your equipment falls on them.

Here are some hoverfies from the garden taken using this setup:
Eristalis pertinax - female

Myathropa florea - male

Platycheirus albimanus - female

Syrphus ribesii - female

Thursday, August 29, 2019

Protective Silicon Gel camera cover

I have previously posted about using a shoulder strap to carry my camera with the 100-400mm lens fitted so that it is handy when wildlife appears. This has been successful and it has led to taking a lot more shots of things like birds in flight which I would otherwise have missed. The downside is that the camera and lens inevitably get banged against things - rocks, gates, etc. I have a neoprene lens coat on the lens which has done a pretty good job of protecting it, but the camera body has picked up some scratches - particularly on the corners. So I decided to try a Silicone Gel cover to provide a bit of protection to the camera body. After a bit of research, I bought one from Amazon designed specifically for my camera body.

Here it is on the camera:

and here it is in carrying position on the shoulder strap:

It is not particularly pretty, but it fits the body pretty well and certainly does the job of protecting the corners from bumps and scratches. The controls are all accessible and I haven't found it gets in the way of using the camera. So far, I would consider it a success.

Tuesday, August 27, 2019

Focus stack of Common Darter taken in the field

Yesterday afternoon was very hot and it got to 34C in my Peterborough garden. At this time of year there are lots of dragonflies visiting the garden, especially Sympetrum striolatum (Common Darter) and Aeshna mixta (Migrant Hawker). The Sympetrum like to sit on the tips of the bamboo canes supporting the runner beans (and also along the washing line!) and there were at least a dozen around (plus a S. sanguineum (Ruddy Darter), which proved to be rather shy and inapproachable!). These make good subjects for experimentation and it is of course possible to position a few extra canes so they are at a more convenient height and better situated with respect to the light and the background.

My setup was Canon 80D with the 100mm F2.8L macro lens on a monopod (Manfroto MPMXPROC4). One problem I have found with this is that the lens hood for this lens (Canon ET-73) is very deep (80mm) and, given that the distance from the front of the lens to the subject at 1:1 is only about 90mm, you end up almost touching the subject with it. In full sunshine like yesterday, a lens hood is fairly important, so I bought a VHBW-tec copy of the ET-73 from eBay (since the Canon branded item is ridiculously expensive!) and cut it down to 40mm. I find this modified hood is still sufficient to avoid flare, but provides a more comfortable working distance.

Even when it is this warm, so that they are very active and alert, Sympetrum are reasonably approachable. The knack is to move slowly and steadily and avoid any sudden movements, especially when raising your hand to the shutter release button - since this is a movement made rather close to the dragonfly. One of the things I like to do is to try and get some real close ups, usually of the head. I wanted a high shutter speed and a small aperture to get the necessary depth of field, so I set it to manual mode, dialled in F11 and 1/400s and set the ISO to auto. With plenty of patience, I managed a number of shots like this:

Sympetrum striolatum, Canon 80D, 100mm F2,8L Macro, F11, 1/400s, ISO 1250

I quite like this one because the wing venation is sufficiently out of focus and the body mostly shadowed so that attention is focused very much on the head - and the depth of field is sufficient for the whole head to be in focus. It also shows the striped legs rather nicely - this is where the name "striolatum" comes from!

The other thing I wanted to experiment with was trying to get sufficient depth of field to get the whole insect in focus. Now S. striolatum averages around 40mm long with a wing length of around 28mm. My 80D has an APS-C sensor which measures 22.3 x 14.9mm. So, to fill the frame with a side view of the insect, I will need a reproduction ratio somewhere in the range of  half life size (1:2) or a little less - which will require me to be about 30cm away from it. Looking at the depth of field tables, even at its minimum aperture of F32, the 100mm macro will deliver a depth of field of a bit under 10mm at these settings. So I am not going to be able to get even the nearer wing tip in focus as well as the body.

The obvious way around this is to take a sequence of images at different focal points and stack them. There are two ways to do this: either change the focus between shots or keep the focus fixed and move the camera relative to the subject.

Manually changing the focus in controlled steps is difficult. It is possible to automate it using the lens focus motor, for example, using Magic Lantern addon firmware for Canon cameras. Unfortunately, there isn't currently a version of Magic Lantern for the 80D. It seems that porting it to the Digic6 processor has proved difficult and the problems have not yet been ironed out. I have successfully used Magic Lantern with my 60D and I have used this method to capture stacks of fungi - so perhaps I will do another post about that.

Moving the camera backwards and forwards is more straightforward, so I decided to try a simple way of doing this - which is rocking backwards and forward whilst taking burst of pictures using the camera's high speed shutter mode. The maximum burst rate for the 80D is 7fps. Clearly, since the camera is going to be moving, this requires a high shutter speed to avoid movement blur, so I set it to 1/1000s. Since the depth of field is going to be handled by stacking, you can afford to open up the aperture to get the ISO down. I found that F5.6 would give me an ISO of around 1250-1600. The 80D's high ISO performance is very good so I was quite happy with this, but the depth of field of each individual shot would be a bit under 2mm. One thing I should have done was to switch to capturing JPEG images (rather than raw CR2). It takes much longer to store raw images and the camera's buffer fills up at 24 shots, after which the frame rate drops precipitously. This doesn't occur if you capture only JPEGs. The processor can keep up and you can keep shooting until your SD card fills up! Anyway, I found that sequences of 24 shots were sufficient for this purpose.

Sympetrum striolatum from a stack of 16 images, Canon 80D, 100mm F2.8L, F5.6, 1/1000s, ISO 1600, stacked using Zerene Stacker 1.04

This images is produced from 16 shots stacked using Zerene Stacker. I didn't start quite far enough back and the wind tip is not quite fully covered and there is possibly a bit of movement in the wings. I also stopped just too soon and the bristle along the far, rear leg are not quite sharp. However, these are living beasts and they don't keep still - even if they appear to sit still for quite long periods. In particular, they are constantly moving their heads and track every movement you make - like rocking back and forwards near them! Here is an animation of another stack in which the wretched beast decided to clean its eyes with its front legs just as I pressed the shutter button! It is animated at 4fps so, since it was shot at 7fps, it is roughly half real speed.

It is interesting to note how much the subject moves around in the frame. Since I have the camera on a monopod and am moving towards it, the fact that it rises up across the frame is not unexpected due to the pivoting motion of the monpod. But the forward and backward swaying shows I didn't get my forward movement very smooth! The degree to which Zerene managed to correct for these shifts and accurately align the images in the above stack (which suffered similar subject movement!) is quite impressive.

Sunday, August 25, 2019

More trail camera examples

Here are a couple more examples captured last night and this morning in a different part of the garden using my Browning Spec Ops Advantage. Ignore the time stamps on the videos, I forgot to reset the time and date when I put the freshly charged battereies back in to the camera!

Here are a couple of the cubs, about 10pm last night (24th August). They are now pretty nearly full grown and as big as an adult, if not quite as heavily built yet. They are eating windfall pears.

And here is one captured this morning of a Grey Squirrel - just to show that quite small animals do trigger the camera successfully:

It either got very warm in our garden last night, or the camera is rather over-estimating the temperature!

Saturday, August 24, 2019

Browning Spec Ops trail camera review

I have had this trail camera since March 2019, so getting on for 6 months at the time of writing. Whilst I had been vaguely thinking about getting one for a while, what actually triggered it was the appearance of a burrow dug under the floor of our garden shed last winter. We thought this was likely to be a Fox and wanted to investigate. It did indeed turn out to be a vixen and she proceeded to raise her family in the garden - followed in detail using the trail camera which has been operating most nights and has recorded about 3,800 files - mainly video. So I feel it has been well tried out!

So, it is a Browning Spec Ops Advantage purchased from NHBS.

It is advertised as capturing 20Mpixel images, but this is the usual hype. Like pretty much all such cameras, it basically captures about 4M and interpolates. It will take full HD video with audio at 30 or 60fps and I have found the quality is quite good. See the examples below.

Night vision is provided by "invisible" infra-red LEDs. Trail cameras are usually equipped with "low-glow" LEDs which have a peak output about 840nm which is just visible to humans and most mammals as a dull red glow. Alternatively, they can be equipped with "no glow" LEDs with peak output above 900nm which are beyond the visible range of us and most other mammal species (hence referred to as "invisible" or "black-light" in the advertising). The advantage of "no-glow" LEDs is that they are less likely to disturb the wildlife or be spotted (and stolen!) by other humans. The disadvantage is that, because they are harder for the sensor to detect they produce less bright images or have to be run at a greater intensity and hence, consume more battery power. I have found that the night-time images are fine for my garden. The claimed range is 80 feet, but I haven't had occasion to use it at anything like that range.

Speaking of power, it uses 8 x AA batteries which fit in a metal tray.

The manual insists that alkaline batteries are necessary and advises the use of extremely expensive and environmentally unfriendly Lithium batteries. If you look at Browning's web-site it says it should not be used with rechargeable batteries. This is rubbish! It works fine with NiMh rechargeable batteries - which is what I have been using (Panasonic Eneloop Pro 2500 mAh). It won't run for so long though on rechargeables and, when a freshly charged set are inserted, only about 76% battery capacity is reported. The web-site gives various tables on how long you can leave it out - which, of course, depends very much on how often it is triggered, whether you are taking photos or videos and the length of videos it is set to record- the greatest drain being use of the LEDs to record videos at night. I have just recharged my batteries for the second time. So it has run for something like 2.5 months on a charge, sometimes recording several hundred, 10s videos in a night and rarely less than 30-40.

I had one early, bad experience. I set the camera up in a position that put it in full sunshine in the middle of the day with the sun shining directly on the metal back plate of the camera. It got too hot to touch and cooked a set of batteries! They were ruined and wouldn't hold a charge thereafter. So be careful how you site you camera.

Another important feature, when choosing a trail camera, is the trigger time and recovery time. Trigger time is the interval between the camera detecting movement and the shutter being fired. This is setable between 0.4 and 0.7s on this model. 0.4s is at the low end, though there are camera offering down to 0.2s.I find it has been good enough for my use. There are times when something has run or flown through the field of view where you only get a fleeting glimpse of it disappearing off the edge of the frame, but these are rare. The recovery time, it the interval before it can be triggered again and is 0.8s on this model - although you can set it longer. If there is a lot of activity, it may be good to set a longer pause between triggers or you may be overwhelmed (and run the batteries flat very quickly)!

Setting up is fairly straightforward. There is a door on the front of the lower portion of the camera body, which is secured by a pretty formidable clip - so little chance of it coming undone accidentally.

Behind the door, you can see the 2 inch, colour LCD screen which allows you to view what the camera is seeing when positioning it and also to check what it has recorded. The former use is invaluable, I can't imagine how you would set the camera up without being able to see what it is seeing, but I wouldn't like to have to actually view my recordings on this tiny screen. Like most LCDs, it is pretty difficult to see in bright conditions. Beside it is the on/off switch and a mode button which switches between the main modes of the menu system. Below that is the menu navigation set of switches with "E" for enter in the middle and up-down and left-right selector switches arranged around it. Finally, the battery tray eject button is at the lower-right. This is a pretty stiff catch and the getting the battery tray in or out usually is a bit of a struggle - it does not slip in or out easily! On the side, you can see the slot for the SD card. A fairly high spec SD card is recommended, mine is a 32GB cat 10. The files for a 10s HD 30 fps video are typically around 13-18Mb.

The menu system is explained fairly well in the manual, but you will certainly need the manual handy if you want to change settings. The most basic operations are initially setting the time and date and selecting the main parameters of still or video, resolution and, if you are capturing video, the fps (30 or 60) and duration. One useful setting allows you to keep recording video as long as movement is detected up to a max of 5 minutes, providing there is enough light so as not to require illumination with the IR LEDs. I have it set to take 10s video clips with this feature enabled - and have occasionally got 5 minute videos during daylight, but I frequently get videos up to 20s or so at night when an animal stays in view. I think the suppression when the LEDs are used is not complete.

Browning is an American company (although the camera says "Made in China" on it) and somethings about it are resolutely American. Pictures and videos have an (optional) strip along the bottom on which the time, date, temperature and other details are shown. You can set the temperature to Celsius, thank goodness, but you cannot set the date to European format - you are stuck with "mm/dd/yyyy" - which I do find rather annoying! It would seem reasonable to allow the date format to be set as well as the temperature units.

The camera comes with a strap for fixing it to a tree. The strap goes through slots cut in a metal plate fixed to the back of the camera and there is a closed-cell foam pad that fits over this - going between the back of the camera and the tree or post. The strap is about 5 feet long, so will go round a pretty big tree.
The manual suggest you position it at about chest height, ideally where the target animals will cross in front of it (rather than coming directly towards or away from the camera). If you strap it to a tree, it is quite tricky to angle it correctly. It often needs a wedge shaped bit of wood behind it to angle it down a bit. The camera has a standard tripod bush at the bottom so I have found that duct taping a ball and socket mount to a post or whatever works better.

Various mounting devices, security locks and secure mounting boxes are available as accessories - although they are pretty pricey! Clearly, if you leave it out in the woods somewhere, there is always a chance that somebody else will find it and pinch it! Whilst padlocking it to a tree may help deter the casual thief, if somebody spots it out in the wilds and really wants it, you are not going to stop them easily.

Trail cameras are triggered by a Passive Infra-Red (PIR) detector of the type commonly used in burglar alarms. What this looks for is a moving object that is significantly warmer than its background. So mammals and birds work fine. I find that, in my garden, pigeons, Blackbirds, squirrels and even Robins trigger it. So I think it would work fine to detect something like Hedgehogs in your garden and is ideal for Fox, Badger, deer and the neighbour's cat and children. However, you do get plenty of false positives: on a bright, sunny, day vegetation warmed by the sun and waving in the wind, especially if its background is in shadow will trigger it and in very windy weather when vegetation is thrashing about wildly, it can get triggered almost continuously - so you can end up with dozens or even hundreds of useless videos to delete!


In our resident fox family, mom has an injured front leg and limps very noticeable. We think it is an old injury that has healed. When cubs jump on her, she shows no sign of pain or avoidance. She seems to cope extremely well with her disability. She had 4 cubs initially. Here is the first time we saw a cub above ground - taken at 2am on 1st April as you can see from the strip added to the bottom photo. This is lit by the IR LEDs so you can see the darkening towards the corners where the illumination isn't reaching as well and eye-shine is very evident:

Here is a daylight video of mom with her four cubs taken early evening on 1st May. At this time they were very regularly out during the afternoon, especially if it was warm and sunny:

Here is a much later compilation of clips taken on 19th July. These were taken early in the morning, so there is not enough light for colour, but there is enough not to rely entirelyon the IR LEDs - so the scene is evenly lit. Down to 3 cubs at this time, and here they are having a play with mom on the lawn:

And here is a more recent compilation showing how they jump the 2m high fence between our garden and our neighbour's. The first clip is a night shot with LED illumination, the second is shot around dawn, so B&W but evenly illuminated and the final clip is in daylight. Mom can jump that fence despite her limp!

Thursday, September 06, 2018

Opticron DBA VHD+ 8x42. review

My previous pair of bird watching binoculars were Opticrom Imagic BGA 8x42s bought in February 2000. During a trip to the Spanish Pyrenees in May, we had a couple of very wet days during which my bins got well rained on and subsequently developed internal condensation. Not good! On subsequent investigation, it turns out that one of the barrels has been bashed at some time and was a bit bent - and that had broken the waterproof sealing. I got a quote from Opticron to fix this - £125.
My old Opticron Imagic 8x42
The bent barrel
So, time for a new pair of binoculars. I did lots of research on the Internet and then went to the Bird Fair to try out a wide range of optics. Since the old pair of Opticrons have done me well for 18 years and I don't feel like paying the crazy prices for the likes of Leica, my research had inclined me towards the latest offerings from Opticron.

Before I go any further, I should say that my eyesight is decidedly not of the best! I am 64 and, in 2003 suffered a rather quickly forming and severe cataract in my right eye. This was operated on and I have had an artificial lens since. More recently, a cataract has been steadily forming in my other eye and it is now quite perceptible - putting a slightly yellowish, foggy cast over my vision on that side - although not yet severe enough to operate. So someone younger with perfect vision may definitely be able to perceive differences between optics that are lost on me!

The optics pavilion at the Bird Fair allowed me to try out a range of high end bins: Leica, Zeiss, Swarvoski, Kowa and Opticron (at the In Focus stand) next to each other and on the same subjects - a couple of Little Egrets fishing in Lagoon 1. I found that the current, top end binoculars clearly gave a better image than my old Opticron Imagics - brighter, more contrasty - but I could not see any difference between the top brands costing well over £1000 (or over £2000 in a few cases!) and the top end Opticrons costing £300-600. There is not a lot to distinguish them on things like weight, field of view (pretty much identical in all the ones I looked at) or closes focus distance (1.8-2m in all of them with the Opticrons at the low end of this range). So the upshot was - I bought a pair of Opticron DBA VHD+ 8x42. I did also look at the 10x option, but my hands are too shaky these days and I cannot hold them steady enough.

Opticron DBA VHD+ 8x42
I have now had two trips using the new bins - a three day trip round North Norfolk and a week in the Black Isle, northern Scotland plus the local birding in between. So, this review is based on a couple of weeks of intensive, daily use. I have found the new bins extremely good. Physically, they are no different in size or weight from my old ones, but the clarity and brightness of the image is perceptibly better. They focus down to about 1.8m - which is useful for dragonflies, and about the same as the old pair. However, I am less happy with the case and strap supplied with them.

Fist, let us consider the case. The old Opticron case was a soft leather affair with a zip and its own strap. It has survived 18 years of use with no problems. About the only sign of wear is that the gold-coloured lettering of the Opticron logo has worn off!
Old case
The new case is a soft Cordura affair with no strap. The idea is that there are cut-outs so that the binocular strap acts as the case strap as well.

New case
This might be OK, except that the fastener on the case is pretty useless. It is a sort of metal button, over which you are supposed to press a slit in the leather tab on the lid.
The fastener
It turns out that it is very difficult to fasten this properly. The case is soft and the fastener falls over the gap between the barrels of the binoculars, so when you try to press the flap over the stud, it just sags into the gap and it is quite a struggle to get it on satisfactorily. Then, if you try and pick up the binoculars in their case by the strap, and the flap is not fully fastened, all that happens is that you pull the bins out of the case! This has happened repeatedly!

Secondly, consider the strap. The old strap was simple - just a broad neck strap with two narrower, nylon webbing pieces at each end to loop through the lugs on the binoculars. The new "neoprene bungee strap" is more complicated. It has a broad neoprene neck strap with narrow nylon webbing pieces at each end as before, but these are terminated in quick release buckles. The other end of the quick release has another narrow nylon webbing strap which goes through the binocular lugs.
Fastening the "Neoprene bungee strap" to the binoculars
The problem with this is that, either side of the quick release, there is a bar-buckle that fasten the loop of webbing that goes through the loops on the quick release buckle on one side , so that its lengths can be adjusted, and a second one to fasten the loop that goes through the binocular lugs on the other side. These bar-buckles tend to slip - especially the one nearest to the binocular lugs. Normally, I would put the strap through the buckle an extra time, but the bits of strap nearest to the lugs are too short to allow this. This has been a real problem - I have had the strap come undone almost daily because the fastening of the loop that goes through the binocular lugs has slipped. This despite my best attempts to thread it back through the bar-buckles an extra time to stop it slipping.

I really do not understand why Opticron decided to put the quick release buckle in this strap! What function does it serve? All it does it make three points of failure into each end of the strap instead of just one in the old style strap. Opticron do a harness which has a quick release system. It seemed logical to assume that the quick-release on the bungee strap would be compatible with that on the harness so the bins can be quickly switched between them. But this is not so! The quick release buckle on the harness is much wider than that on the bungee strap. So why they put a quick release system on the bungee strap remains a mystery!

Opticron Harness quick-release on the left and bungee strap quick-release on the right
In conclusion, the new binoculars are great and I would thoroughly recommend them, but the case and strap they are supplied with are not so good. In particular, the strap has been a right pain so far - it keeps coming undone. For that reason, and also because it might help holding the bins still with my shaky hands, I have decided to replace the neck strap and try out the harness. Once I have had some experience with the new harness, I will write a review of that too.