I have spent the last several months putting a series of fine lenses through my own kind of tests. No, I don’t shoot fine-lined charts or produce MTF specs, but I do work a lens as best I can for my particular style of photography. What am I finding out through all this lens juggling? I thought I would write down a few points that are pretty much now axiomatic with me. Before you raise objections, these are just my opinions. I know quite well there are other ways to take photos, etc., and yada, yada, yada. Hear me out, please. If the points are useful, check them out. If not, forget about it.
What follows is provisionary, but most of these issues seem to be hardening up into what amount to rules in my little book of photo rules, what I have learned. See what you think.
EXOTICS AND INDUSTRIALS
The old exotic Nikkors (and other) industrial lenses have very, very special qualities. They do, but what they do not have is the standard coatings, etc. that we have come to expect from lenses these days. And for my use, many have too short a focus-throw as well or none at all. Many require special mounts, which is no problem. The result of my tests is that these industrial lenses are for specialized work, just as I’ve always told myself. They can never become my “walk-around” lens, meaning the standard lens I most use on a tripod because, even though some are highly corrected, their age shows through, probably just as my own does. They really are specialized lenses.
This observation on the industrial exotics has been disappointing because I have put a lot of importance on this group of lenses. They indeed are very remarkable, but an additional remark has to be that the results of these lenses don’t look (generally speaking) as good as, say, the new Zeiss Otus APOs. Period, end-of-story. Yes, I have learned to use the exotics pretty well, but perhaps my time might be better spent learning to use the Otus Zeiss really well, because in the long run, they produce better images… at least for my work and IMO.
This includes the Printing Nikkors, the El Nikkor APOs, the CRT-Nikkor, the Repro Nikkor, and so on. These exotics are incredible lenses, lenses with special character, but despite that special character, they show their age. If I look carefully, there are qualities that I do not like, which are usually color-related. Yes, I can work them and still use them, but they no longer appear as the lens panacea that I once thought they were. Nothing ever is… well, the Otus lenses come close.
STACK WIDE-OPEN
I generally stack with a fast lens wide open, so that I have plenty of bokeh. Then, any stacking I do effectively paints focus only in the areas I want to bring out or highlight, and not just foreground images, but anywhere in the image I want to have in focus. This is the technique I most often use, concentrating on the compositions, since the technique is pretty much second nature by now.
I DON’T STACK AT NARROW APERTURES
I used to do this, but I don’t anymore. And I don’t stack at the optimum sharpness aperture for a lens either, because I would rather have the bokeh I get at wide apertures, which I don’t get with most apertures at their optimum, which is often something like f/5.6. Sharpness at the optimum aperture for a particular lens is not something I look for (in focus stacking), but something I paint in with layers of razor-thin focus at wide apertures using fast APO lenses.
APO (Apochromatic)
Yes, yes, and yes to APO lenses. To my eyes and in my work they are superior to lenses that are less well-corrected. I believe the Zeiss Otus line has shown us this.
SHORT STACKS
I have stacked in so many ways that I have forgotten some of them, like “short stacks,” which are just to give an impression, for me a proof-of-concept. A short stack is 5-6 images stacked, and there are ways to use them.
SHORT STACKS, NARROW APERTURE
However, one good way to make a short stack is to take images of just the main subjects in the frame at high apertures, so there is a lot of fine detail, simulating depth-of-field. For example, if there are three flowers, then take a carefully focused shot of the center of each of the three flowers and stack them using only DMap in Zerene Stacker. The result can be pretty interesting.
STACKED COLOR
It is pretty much axiomatic that stacked color, no matter how well done, sucks compared to the color in a single shot image. This can be tempered somewhat by using as much DMap and as little PMax as possible in the stack-retouching with Zerene Stacker. When we choose to stack, we choose a lesser quality of color rendering, and the apparent added depth-of-field has to make up for or to compensate for the color loss.
STACKED “SHARPNESS”
The same general idea is true for whatever we want to call “sharpness,” be that resolution, acutance, or whatever we could agree on. Stacked images have somewhat degraded “sharpness,” by their very nature. If there is absolutely no movement in the subject, the effect can be OK, but if there is any movement in the stack, forget about it. They do not compare to a carefully done single-shot image with the same lens.
STACKS RETOUCHED WITH SINGLE-SHOTS
Another useful technique is to stack images using a fast, highly-corrected lens wide-open, and then take a single-shot photo of the same image (the same exact pose) at a narrow aperture, like f/16. Then, taking the stacked image (with good bokeh) as the base, use the f/16 photo to copy (retouch) only crisp areas where they would improve the impression of sharpness, like the center of flowers, and so on. This can be quite effective.
BELLOWS AND RAILS
We should all know by now that the available stacking software prefers that we shoot (in order of quality):
(1) On a bellows with the lens fixed by the front standard, and the camera (which moves to focus) on the rear standard.
(2) Moving the standard focus ring or helicoid.
(3) Attach the camera (with lens attached) on a focus rail and move the whole setup down the rail.
As for me, I tend to use the second option, moving the focus ring, but I like lenses with a large focus-throw. Lenses with less than 360-degrees of focus throw are more difficult to use, and 90-degrees or less of focus throw are damned hard to use. I might as will put it on a focus rail.
WHEN ALL IS SAID AND DONE
Most of the standard Nikon lenses that we all own are not corrected highly enough for me to use anymore. I save a few (the sacred trinity of 14-24, 24-70, 70-200) for family shots, concerts, sports, or whatever. The others I never use, so I am selling them off. I also have lots of older AIS Nikons (which I will keep) that are indeed nice, but not corrected well enough, so that the final result is in some ways a little too harsh. I love the Nikon 16mm and have two versions, which I often use.
I bought and like the Sigma 24mm ART lens and will keep it until the Zeiss Otus wide-angle lens is issued. It looks like I will send the Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens back to B&H, but I am still deciding.
When all is said and done, I end up using the new Otus-level Zeiss lenses, mostly because they are very highly corrected and whatever coatings they have seem sufficient. They are just a better mousetrap as far as I am concerned. I am not brand-loyal, but quality-loyal. For years I used the Voigtlander 125mm f/2.5 APO-Lanthar lens for my close-up and macro work, but as soon as I had the Otus lenses, I set it aside, to be used only on occasions. The Otus series (with the 135mm APO) are a landmark in lens history for the Nikon.
I am sure I am forgetting some points, and there are others I am still vetting, but, in general, that is what I am working with and how I work.
Discussion would be great.
[Photo here with the Nikon D810 and the Zeiss Otus 55mm, f/1.4 APO lens, stacked.]
