pawelfoto wrote: ↑Tue May 18, 2021 3:34 am
I am delighted with your photos. great colors, sharpness and surprisingly large depth of field. I really like little "secondary heroes". I believe it wasn't easy to catch the focus in the field. I have experienced that models do not want to stand still. How long does such a photo session take for you? I wonder how many unsuccessful photos go to the basket for one hit. What kind of diffusers do you use on speedlite? Is all the light from the flash or the background is partially natural (what shutter speed and ISO?)
== best, Pawel
Thank you. Those are interesting questions. I like that.
My approach for this sort of imaging is based on the use of very small apertures. The Laowa 100mm 2X macro lens that I am using goes from f/2.8 to f/22. I get beyond the minimum aperture of f/22 by using a pair of 2X teleconverters. With them in place I get apertures of f/11 to f/90. At the moment I am using f/45 all the time. The effective aperture is smaller than f/45, increasingly so as the magnification increases, as set out in the top post.
These very small apertures give a relatively large depth of field. However, the image quality is severely degraded by the effects of diffraction. Fine detail is erased completely, and larger scale detail is greatly softened. Once fine detail has been lost it cannot be recovered, but with suitable post processing it is possible to make better use of the larger scale but very soft details that remain. The finalised images need to be kept small because there is insufficient detail for large outputs. How large you could go will vary from image to image and will depend on personal taste, but I simply keep my outputs at 1300 pixels high. They are processed for best viewing as a whole, from a normal viewing distance, at that size, i.e. not upsized or downsized, and with no provision for zooming in/pixel peeping. (They are incidentally also prepared for best viewing in subdued light on a calibrated monitor using the sRGB colour space.)
The following illustration shows two real world examples. I have chosen these because they suffer from particularly severe image degradation and this serves to illustrate the issue clearly.
I shoot raw, but there are small JPEGs embedded in the raw files. These are what an out of the camera JPEG would look like. On the right below we see one of these embedded JPEG files that has been resized to 1300 pixels high. We are looking at the central portion of that 1300 pixel high JPEG at 100%. On the left below we see the same area of a 1300 pixel high processed image. (These were captured with an A7ii rather than the A7sii I have just purchased.) As mentioned in the top post, I used DXO PhotoLab, Lightroom and Topaz DeNoise AI to process these images, but my processing workflow changes quite often and the products I use change from time to time.
1867 1 A7ii+2x2+100atF300ish processed vs OOC by
gardenersassistant, on Flickr
This is diffusion I am currently using (this changes from time to time too), shown here on an A7ii.
1887 1 by
gardenersassistant, on Flickr
Because of the very small apertures I am using I need to throw a lot of light on the scene. In fact, what with the light loss from the diffusion and the rapid falloff in light intensity as working distance increases, I can't put enough light on the subjects to use base ISO. I rarely get as low as ISO 800, and it is most often in the range of 2000 to 4000, sometimes higher at low magnification. I am essentially working in a low light situation. This is where the Sony A7sii came into the equation.
Because of the loss of fine detail I don't need many pixels on the sensor. Also, there is a school of thought which says that post processing will work better, especially at low light levels, with larger pixels. This is disputed, and was the cause of an argument, which I couldn't follow tbh, starting with
this post in a thread I posted at dpreview.com asking whether there would be any advantage for what I'm doing in using a camera with fewer but larger pixels. Although I couldn't follow the details, my feeling was that the people arguing for the advantage of larger pixels in my particular context had the best of the argument. So I decided to try the A7sii, which has only 12 megapixels and is renowned for being a good low light camera, at least for video. I don't think it used too much for stills.
I haven't used the a7sii much yet, and I may be in a false honeymoon period where I'm seeing what I want to see in order to justify the cost, but I do have the impression that it is producing results that are at least as good as with the A7ii. And I suspect that it is picking up more from dark backgrounds. I don't like the completely black backgrounds that you sometimes get with flash. But as illustrated in these examples even when background areas are rather dark, they often have a little colour to them, and when they don't they still aren't completely black. I'm liking the look of that. I don't know if this is flash or natural light it is picking up. That probably varies from scene to scene.
It is also possible that the subjects are coming out better. I have the impression (but possibly it is imagination or wishful thinking) that they seem to have a bit better clarity, or something. I can't put my finger on it and it isn't practical to do real world like for like comparisons in the field between the A7ii and the A7sii, so I'm never going to be 100% certain about it.
One thing I am fairly certain about after my first two sessions with the camera is that I'm getting stronger focus peaking signals than with the A7ii, and that is very helpful. I think it is probably increasing my success rate as far as focusing is concerned.
You asked about the length of sessions and success rates. That particular session was just under two hours. I captured 529 shots and kept 93 of them. On the face of it that is a "success rate" of around 17%. However, I think you need to be careful about interpreting "success rates".
For example, I often capture a lot of shots of a subject to increase the probability of getting one that turns out ok. Suppose I take 10 shots of a subject and there turn out to be 6 that I would be prepared to use. But I only use one, because the pose is the same in all of them. Is my success rate 10% (using just one out of 10 attempts) or 60% (I could have used 6 of the 10)? And what would your success rate be for the same 10 images. You are probably looking for different things in an image than I am. Perhaps for you none of them would be usable, or perhaps all of them, or anything in between. It also depends on how difficult the shots are. Shots get more difficult the smaller the subject is, the more awkward it is to get at, the more easily it is disturbed, the more it is moving around, the more what it is on is moving around (e.g. on a leaf in a breeze), the more particular you are about exactly where the plane of focus falls and the more frequently you change the framing/magnification between shots. So if you are shooting large subjects which are stationary for as long as you want to take and are difficult to disturb (like crane flies for example in my experience) then you could reasonably expect a high success rate. Conversely, with a smaller subject that is moving around a lot and you are moving frequently between environmental, full body and head shots you could reasonably expect a quite low success rate.
As it happens, I like photographing little animals as they move around. For example, here are three sequences from the test session. How should the fact I capture sequences like these affect the interpretation of that "17% success rate"? I don't know.
1892 Illustration 1 - Three sequences by
gardenersassistant, on Flickr
As to shutter speed and ISO, I generally use flash sync speed for flash work. At least, I thought I did. I thought it was 1/200 sec for the A7ii and A7sii, but I just looked it up to check and it turns out to be 1/250 sec, so that's what I will use in future. Thanks for the nudge.
[EDIT: It turns out that it does need to be 1/200 sec, despite what the specification says. Presumably there is a synchronisation issue between the camera and the non-Sony flash that I'm using.]
ISO varied from 640 to 5000 for the images I kept from the test session. I use a manual flash and I keep it running at 1/4 power so I can keep shooting every one to two seconds for extended periods without having to wait for the flash to recharge. I use ISO to control the lightness of the image.
