It looks as though I may be in for a major change of kit for photographing small invertebrates, and possibly larger ones too. What makes this potential change particularly interesting to me is that it brings me back close to where I was at the start of this thread six years ago. At that time I had been using bridge cameras and close-up lenses for several years to photograph invertebrates. In order to improve my image quality I purchased a Canon 70D dSLR and a 100mm L macro and an MPE-65 1-5X macro lens. To my surprise and disappointment this new, specialised and high quality kit did not produce higher quality images of invertebrates. (The 70D was good for flowers, but even that was with a telezoom lens with and without a mild close-up lens, so I quickly returned the 100mm macro and MPE-65.) Since then I have periodically revisited macro lenses and associated kit and have accumulated various lenses (including repurchasing an MPE-65), extension tubes, teleconverters, reversing rings, flash units, brackets etc. But for invertebrates I have kept coming back to close-up lenses on telezoom lenses, either on fixed lens small sensor bridge cameras or on larger sensor APS-C and, more recently, micro four thirds cameras.
The core issue turned out to be depth of field. I like to photograph insects using whole body shots and "environmental" shots from further out. Although I like looking at other people's closer-in shots of flies' eyes etc, I don't often do that sort of shot myself. Especially for the whole body shots, I like to have as much of the subject in focus as I can. Since I work out of doors with active subjects stacking is not a suitable general purpose approach, although I have used it occasionally for invertebrates (and I do use it a lot for flowers). I therefore generally use single shots for invertebrates and in order to get as much depth of field as I can I use very small apertures. These small apertures cause a big loss of fine detail because of diffraction, and this brings high quality kit down to much the same level as lesser kit. In fact with the various kit I have tried over the years the results have been pretty much indistinguishable irrespective of sensor size, pixel count or lens quality.
This new branch in the story started a week or two ago. My wife and I are both on the highly vulnerable list and so have been in full lockdown for many weeks now. My only photographic opportunities are in our garden, and while the flowers have been good this year the number and variety of invertebrates has been even smaller than usual (they have been declining throughout the decade and more we have lived here).
1646 Illustration 1 Pond by
gardenersassistant, on Flickr
We have a tiny (4' x 3') pond and it recently came alive with two sorts of flies that so far have continued to turn up every year. One sort is long-legged flies, which are smallish and highly active, only settling - at most - for a few seconds at a time on the lily pads or surrounding stones and foliage. They have highly reflective bodies and in the sunny conditions in which they appear the water on and around the lily pads produces very strong highlights. They are difficult subjects, in a difficult environment, especially as I often have to reach out over the water to get at them, which can make it a surprisingly strenuous activity, especially on the hot days in which they are most in evidence.
The other flies are small, around 3mm from head to the tip of their wings when folded up on their backs. They are not quite as hyperactive as the long-legged flies, but they do tend to wander around unless you can catch them supping on something, typically the carcus of a similarly sized dead fly. They don't have particularly reflective bodies, just a white patch on top of their heads which is prone to blow out. However, depth of field is an issue. Unlike with larger flies such as the long-legged flies, or even larger flies such as the hoverflies which occasionally turn up at the pond, I have not been able to get sufficient depth of field to produce images that I am comfortable with. As well as the overly limited depth of field, the transition between in-focus and out of focus areas seems very ugly to me.
Given that these flies were about the only invertebrate subjects I had available to me, I decided to take my time and try harder with them and in particular to see if I could work out how to get more acceptable results with the small ones. I tried over and over again with my bridge camera and close-up kit. No matter how hard I tried, it simply wasn't working; there was not enough depth of field and no matter how hard I tried in terms of technique I couldn't get around that.
I had a rethink. I knew I could get greater depth of field with macro lenses, reversed lenses, extension tubes etc, but I had only dabbled with that approach, for a couple of reasons. One was that I was already using f/45 full frame equivalent. With some fairly heavy processing I can produce results that I find acceptable with f/45 as long as I keep the output size down to around 1300 pixels high. That seemed to be about the outer edge of the envelope, and my indoor testing had shown that decreasing the aperture further continued to worsen the diffraction softening.
The other reason was the handling characteristics of the macro/reversed/extension tube setups I had tried. I found these setups extremely difficult to use. I was used to having setups that were not overly heavy, which let me zoom in and out easily and quickly to find and frame subjects, and which let me use accurate and fast (enough), non-hunting autofocus at all the magnifications I used. In contrast the macro etc setups were mostly uncomfortably heavy and, whether or not heavy, all of them made locating and framing small subjects frustratingly difficult and all had to be used with manual focus, which I found slower and less accurate than close-up lens autofocus. Manual focus was also a lot harder on my eyes. With autofocus I simply had to put a small focus box over the place I wanted the centre of focus to fall, and for that I only needed to be aware of the outline of the subject. With manual focus I needed to look closely to see when the fine detail came into focus. This was hard work when looking at the whole scene on the LCD screen (the particular implementation of magnified screen options were not suitable for my - hand-held, quick response - purposes). I had to use the LCD screen because a lot of the angles I work at make the EVF impractical. And in the bright conditions in which these flies appeared reflections from the water made it even more difficult to see what was going on. (Reflections on the LCD screen were not too much of an issue as I use fairly deep LCD hoods.)
I decided to have a more thorough look at using ultra-small apertures. My thinking on the diffraction blurring issue was that it was just possible that I might get acceptable results using a couple of Topaz products that I have been using recently - DeNoise AI and Sharpen AI, which between them have five methods which might be helpful, and which have sometimes seemed to have remarkable success with rescuing apparently unusable images. In terms of the weight and awkwardness of the setups, the weight was not going to change but it was possible that with more experience and practice these setups might become significantly more usable. That has been the case with other technologies which have taken me a while to get used to, develop suitable techniques, short cuts, muscle memory etc.
I did some initial handling tests with various combinations of kit involving a full frame Sony A7ii, an APS-C Canon 70D and a micro four thirds G series camera, using EF mount macro lenses with them - Canon MPE-65 1-5X, Laowa 25mm 2.5X-5X macro, Meike 1.5X macro and Sigma 105mm 1X macro. I also tried 1.4X and 2X teleconverters. With an Olympus 60mm macro on micro four thirds I also tried extension tubes.
I did some measurements and calculations for the most likely looking combinations.
1646 Illustration 2 Measurments and calculations by
gardenersassistant, on Flickr
I then went out into the garden to try the combinations which looked most suitable from the measurements and calculations. On the pond I had the small flies and the long-legged flies as subjects. There was also a cucumber spider that had made a nest in a Choisya bush. It is difficult to be sure, but I think the spider was around 6mm in size. It spent most of the time in the not very photogenic position shown below on the right.
1646 Illustration 3 Choisya bush and spider by
gardenersassistant, on Flickr
I started with the pond. The first setup to show promise was the A7ii and Laowa 25mm macro. Because of the shape of the lens I could not attach a front-mounted flash and so I used a top-mounted KX800 twin flash. The Laowa and KX800 are shown here on the 70D. This KX800 setup that I used with the A7ii is a bit simplified compared to the one I generally use with my FZ bridge cameras (shown on the left below). The simplified version (shown in the middle below) has smaller diffuser boxes on the flash heads and no full width diffuser layer in front of the diffuser boxes. The illustration also shows a torch mounted on the side of the KX800 that I added after doing the test shots to help in future with finding subjects and focusing on them. (The torch is fixed with velcro so the direction it points in can be changed if needed to suit a different magnification.)
1646 Illustration 4 Laowa flash setup by
gardenersassistant, on Flickr
I had a short session with the A7ii and Laowa and then a short session with the usual kit I would use for this size of subject, an FZ330 and Raynox 250, using the flash setup shown on the left above. After processing the images from both these sessions I compared them and overall I preferred the look of the A7ii images. However, with such active subjects it is impossible to produce strictly like for like image pairs for comparison, so I was cautious about drawing too strong a conclusion about pairwise comparisons of somewhat similarly framed subjects. I thought it possible that the sharpest areas in the FZ330 images were sharper than the sharpest areas in the A7ii images. That would be reasonable given the additional diffraction blurring that the A7ii images must have been suffering from because of their smaller effective aperture. However, the A7ii images often appeared to have greater depth of field, and I could more often get the subjects a bit larger in the frame at a just about acceptable image quality. Finding and framing subjects was slower with the A7ii and failed more often than with the FZ330, but once I had subjects in the frame my failure rate with focusing seemed relatively low with the A7ii compared to my close-up lens kits when used for this size of subject. I found that surprising given that I was using manual focus, in a hurry, and couldn't see the LCD image very clearly because of the ambient conditions.
There was however one image which pushed my doubts to one side and motivated me that to continue with some more extremely small aperture experiments; the one below. Admittedly I was lucky to have the opportunity and lucky with the exact timing of the shot, and the in-focus areas might not be as sharp as I could get with a larger aperture, with the FZ330 or anything else (including of course the A7ii), but I have never achieved such DOF coverage and subject separation with these small subjects so large in the frame, and as such I found this a very appealing image, and one that I was fairly confident I could not have achieved with my bridge camera setups, or anything else operating at f/45 full frame equivalent.
1646 Illustration 5 1642 13 2020_06_02 DSC02305_PLab3 SP9LR 1300h-DNAIc-DNAI-PS-AISh2 by
gardenersassistant, on Flickr
This made me curious to see what would happen if I used this same, tiny aperture, approach with larger subjects. I couldn't do this with the Laowa because it was too powerful for full body shots of larger subjects. After some more experimentation I decided to try using two setups, a Sigma 105 macro with a 2X teleconverter on the A7ii, and a Canon MPE-65 on the 70D
With the 2X teleconverter, the 105 macro on the A7ii gave me a maximum magnification of 2X, which would complement the 2.5-5X of the Laowa 25. Because of the 2X teleconverter the minimum nominal aperture was f/45 compared to the Sigma 105's native f/22. At the maximum 2X magnification the minimum effective aperture would be f/132, and at 1:1 it would be f/90. This would let me use similar effective apertures as I had been using with the Laowa 25 macro at around 3X magnification.
Here is what the setup looked like, with the front mounted Yongnuo YN24EX flash units.
1646 Illustration 6 Sigma flash setup by
gardenersassistant, on Flickr
The peculiar shape of the diffusers is the result of some modifications I made to try to stop
the diffusers dipping into the pond water so much, which being front-mounted they were much more prone to do than with the top-mounted diffusers I had used with the Laowa 25 (which doesn't have a front thread and so can't use a front-mounted flash).
This setup was big and heavy, but it turned out to be surprisingly usable. Supporting the lens with my left hand it seemed quite nicely balanced, and the focus ring has a short travel (a bit less than 180 degrees from infinity to 1:1, and around 90 degrees from 1:2 to 1:1, which is the range I needed for subject acquisition and framing - which with the 2X teleconverter was actually 1:1 to 2:1).
I also used the Yongnuo YN24EX in front-mounted mode with the MPE-65 on the 70D. I made a mistake with the setup; I omitted to use a 1.4X teleconverter to let me get to the same small apertures, and so in terms of depth of field the MPE-65 results were not comparable with the results from the Laowa 25 or Sigma 105, so I will only refer here to the results with the A7ii, 2X teleconverter and Sigma 105 macro.
As with the Laowa 25, I had mixed feelings about the image quality of the test shots I captured with the Sigma 105 and 2X on the A7ii. I was seeing greater depth of field than I was used to. I also preferred the look of the A7ii images compared to similar scenes captured with my FZ cameras, although I might have difficulty demonstrating this. I think it had to do with the clarity and colour rendering with the A7ii; that Choisya bush has given me a lot of colour problems over the years, but the A7ii seemed to handle that side of things very well, producing results that looked rather natural to me. There were questions in my mind though about loss of (even more) detail from using these especially small apertures. For example, was the next image really any better than I can get with my bridge cameras?
1646 Illustration 7 1644 01 2020_06_07 A7ii+2X+105 DSC02819_PLab3 SP9LR 1300hDNAI-AIS by
gardenersassistant, on Flickr
I think so. The often problematic leaf colour looks good to me, and looking at the legs on both sides of the body it looks to me as though the depth of field is significantly larger than I can normally achieve. And the detail? I'm not sure. It looks borderline to me. Does that spoil the image for me? Not as much as when, with other setups, those leaves look a horrible colour that I can't seem to correct. And I do find the DOF coverage appealing. I think (today) that I can live with that balance of benefits and issues. Tomorrow I might think differently. I had a similar reaction to a lot of the test images.
I found a few of the images of the spider and prey a bit more more convincing. For example, as with the fly image above, the spider image on the left below looks to me like it has more of the subject covered by the DOF than I am used to seeing when the subject is such a large proportion of the frame, especially when as in this case the image has not been cropped vertically. And there is enough detail (albeit not very fine detail) to keep my eyes from feeling uncomfortable.
1646 Illustration 8 Spider DOF and PP raising detail by
gardenersassistant, on Flickr
On the right is what an out of the camera JPEG would have looked like (it is the JPEG embedded in the raw file). On the left is a processed version. It is not very subtle and may well come across as overcooked, but be that as it may I think it demonstrates that post processing can have a significant impact on the look of an image and the amount of detail it appears to have, not least one that is very soft because of extensive diffraction softening.
I think I will need to do more experiments to find the (to my eye) optimal balance. Perhaps I would find a slight increase in apparent detail at the cost of a slight reduction in DOF more comfortable to look at.
This album at Flickr contains some test shots (mainly of the spider and prey) captured with the A7ii, 2X teleconverter and Sigma 105 macro.
This album at Flickr contains some test shots captured with the A7ii and Laowa 25 macro.
This album at Flickr contains some test shots captured with a 70D and MPE-65, with an A7ii with Laowa 25mm macro and with an FZ330 and Raynox 250.
These images were captured in the context of quick tests of multiple options, and so there was a lot of lens changing; I did not attempt to keep the sensors clean. The very small apertures I was using make sensor dust stand out. I have only cleaned up the dust spots in some of the images, and even in those I may well have missed some of them. You are therefore likely to see dust spots in some of the linked images.
The raw files were put through my normal 4- to 7-product processing pipeline:
• DXO PhotoLab (preset)
• Silkypix (preset)
• Lightroom (image-specific adjustments)
• Topaz DeNoise AI (default settings)
• [for some] Topaz AI Clear (default settings)
• [for some] Topaz AI Sharpen (default settings)
• [for some] Photoshop (image-specific adjustments)
I have posted some of these images in
this forum thread.
This is work in progress.
