Notes on Nikon AF-S 105mm f/1.4E ED for Focus-Stacking and Close Work

[Alaun]

Michael, with respect to the "too short a focus-throw", have you tried the "electronic" stacking you can do e.g. with the CamRanger? (Instead of moving the focus by hand using the software and the electronic focus drive system in camera and lens to change the focus distance in small steps) I found this very helpful for doing some shots at work (so I can not show here, sorry).

[Michael Erlewine]

Michael, with respect to the "too short a focus-throw", have you tried the "electronic" stacking you can do e.g. with the CamRanger? (Instead of moving the focus by hand using the software and the electronic focus drive system in camera and lens to change the focus distance in small steps) I found this very helpful for doing some shots at work (so I can not show here, sorry).

I have looked at various "stepper" solutions, but although in winter I work inside, in the warmer months I work outside and already have enough to carry, etc. But that for me is not really the issue. I have no problem using a focus rail (and stepping it myself) and I do this with lenses like the Noct Nikkor, the CRT Nikkor, and others. The question for me is: Since in trying to accommodate the focus-stacking software (Zerene Stacker, in my case), focusing on a rail is said (by author Rik Littlefield) to be the poorest of the main three ways to focus stack:

(1) The best is on a bellows, locking the front standard (with the lens) and moving the rear standard.

(2) Using the lens focus ring.

(3) Using a focus rail.

However, I will be experimenting with the new Nikor 105mm f/1.4 on a rail and with extension, before I decide to keep it or return it. I do try to use any good lenses for my purposes, which are closer than farther. Some work well; many do not.

[Bjørn Rørslett]

The first method is also the only one that will keep the perspective relationship camera-subject constant. Not easily accomplished with modern lenses, though, as they invariably include a focusing helicoid and very often also internal adjustments to the optics along the focusing range (CRC, IF, RF etc.).

Thus what one really needs is a lens head without any extras and capable of returning good optical performance across a wide range of optical magnifications. That would constitute a tall order for any lens. The 105/1.4 E features an electronically-controlled aperture and thus removing it from its focusing mount to make it a lens head, yet still have a workable aperture control is not simple.

The reason for some earlier comments was that it is not fair to blame the lens designers for aspects of its performance not being considered very important to the intended use of the lens. The 105E is a child of the AF age and one should really be enthusiastic it is acceptable to focus by hand instead of complaining about "too short focus throw". It might be possible to reduced any CA already low to even lower levels by adding more glass elements to the design, but the lens is already big and on the borderline of being suited for hand-held use.  It also is optimised for portrait and studio work for which minute residual aberrations off the optical axis is of no consequence. If it is put on an extension tube its designated conjugate parameter domain is violated and accordingly, spherical and chromatic aberrations become more prominent. Again, it is not correct to take the designers to task for such behaviour as it is inherent to any optical system.

I'm stating the above as a general remark as many people tend to ignore such basic facts that extension tubes entail more than adding "air", it has immediate and destructive impact on the optical performance of the lens.

[Alaun]

Maybe my question was not clear. I did not have in mind using a focus rail (your #3) but your #2 using the focus ring on the lens, which can be controlled electronicly as well.

[MFloyd]

Well, I don't care about auto-focus; it's nice for family snapshots.

I trust, this quote is valid yourself and not a general statement...

[Ilkka Nissilä]

After shooting a second day with it, I started to get good results with the D810 and 105/1.4 now, with autofocus, even with moving subjects. I was so used to the D5's responsiveness that I had become sloppy and making an effort to hold the focus point steady caused a marked improvement. Also I refined my fine tune setting from -2 to -3 and all is good now, most images in focus at f/1.4. Mostly the difference is that with D5 even sloppy technique and cornermost focus points are fine, the newer system picks up focus so quickly even on faces.

I did notice an image with color fringing, it was a subject at a fairly close distance (well, closer than full body portrait), on the other hand there were some overexposed pixels which could have accentuated the problem.

[Michael Erlewine]

I totally agree that anything (close-up lenses, teleconverters, extensions, etc.) cannot but degrade a lens. I live by this, which is not to say I don’t try to push the envelope regardless. I have found that adding the K-1 Ring, which is 5.8mm extension (Nikon’s smallest extension), on some lenses does very minimal image degradation. And, since many of the lenses I like the most are not for close-up work, I am getting pretty experienced in this by now.

Bjørn:

I remind you of something you said to me when I wrote to you:

 “Like many things, experimenting may turn out to be useless, but I like to try all kinds of things.” And you responded:

“Now, that is an angle of approach I fully endorse.”

Just to put the question of extension to rest regarding the Nikon 105mm f/1.4 lens, here are some proofs of what Bjørn points out:

IMAGE 1
Here is the 105mm lens with 5.8mm of extension (K1 Ring), but using the focus ring of the lens at f/1.4. This shows me that the focus throw is too short, so that even turning the lens by hand very-carefully, the resulting artifacts are many and too difficult to fix. I tried to remove some artifacts, but gave up.

IMAGE2
Here is the 105mm lens with 5.8mm of extension (K1 Ring) plus being mounted on a focus rail at f/1.4, allowing smaller increments to be made. The result shows how important a longer focus throw is. Had they made the focus throw on the new lens longer, this would be possible. But since they made it for street or sports photography (short focus throw), unless you want to mount it on a rail, you can’t stack-focus well.

IMAGE3
And finally here is an image with the 105mm lens, where it was set to f/10, then removed from camera, thus fixing the aperture there, and then re-mounted on the K1 Ring creating a 9-layer stacked image, where each of the nine layers was focused at a particular part of the image I wanted in fine focus.

As you can see, Image-2 and Image-3 are “useable,” although they could use more retouching. It is not that I did not accept what some users here pointed out. I already knew that, but I like to personal get ahold of a lens and see for myself, whether I can get something out of it that is usable...for my particular work, so please note that. And to MFloyd (and others): These are not general comments on the lens, which I made clear several times. This blog was about close-up and focus-stacking with this lens, whether it was designed for it or not.

And to Alaun’s post about electronic focus:
Unfortunately, I own very few lenses that are not manual. This 105mm was a lens I took a chance on as far as what we are discussing here, but also bought it because I need an autofocus portrait/small-group lens for a project coming up. I have yet to see whether there is much focus-shift and just how much, etc.

I originally thought that this kind of inquiry post would interest those other focus-stacker/close-up photographers, but it caused too much hassle. Sorry about that.

[MFloyd]

I guess "150 mm" is a typo ?

And I'm using "Helicon Remote" for the focus stepping; and Ps for the proper stacking.

http://www.heliconsoft.com

[Alaun]

"IMAGE 1
Here is the 105mm lens with 5.8mm of extension (K1 Ring), but using the focus ring of the lens at f/1.4. This shows me that the focus throw is too short, so that even turning the lens by hand very-carefully, the resulting artifacts are many and too difficult to fix. I tried to remove some artifacts, but gave up."

Ok, my proposal was to -instead of turning by hand- doing the turning by the electronics of the lens, but with the K1-ring, off course you loose this possibility. I think you would need one of those rings, which transmit the electronic signals (like the modified TC's from Erik).

Thank you for the detailed examples!

[David H. Hartman]

Is not the focus throw of most any zoom and most any IF lens dictated by the internal design of the lens? For example I would like a longer throw on my 25-50/4.0 AIS and a shorter throw on my 80-200/4.0 AIS Nikkors. I suspect changing the throw would be at the least a great complication of these lens designs.

Now what about AF lenses where manual focus is secondary to most photographers? Might it have been practical for the AF-S NIKKOR
105mm f/1.4E ED to have a longer throw? One might like it to but that doesn't mean it would be practical to accomplish. It would quite likely compromise other design factors.

I'll probably never even touch the 105/1.4E due to helping a paralyzed woman who was screwed over by a church and school of medicine I won't name but I can read reviews and dream.

Dave Hartman the Infidel

[Ilkka Nissilä]

I don't see how implementing longer throw would be difficult. Gears are not a new invention. In most AF-S lenses the manual focus ring moves at a different angular speed than the distance scale inside, so gears are already likely being used, or some other mechanism which allows the rate to be different.

[David H. Hartman]

I would think that focus in AF-S lenses is done by cams but that's at best a guess. The cam might be shared with the silent wave motor. Maybe someone​ can post a link. I think there was a teardown of the 105/1.4E somewhere online.

Dave

[David H. Hartman]

I found the teardown at Lens Rentals and I remember complaints about gears but I looking at the photos on a smart phone which isn't conducive to my understanding of the lens' features.

Dave who needs suitable reading glasses

https://www.lensrentals.com/blog/2016/12/taking-apart-the-new-nikon-105mm-f1-4e-ed-af-s/

[Michael Erlewine]

I have a 100mm Leica Elmarit-R Macro with a 720-degree focus throw, so of could it can be whatever we wish. The 105mm f/1.4 is, IMO, designed for street or sports, one-off photos. To stack without a long focus-throw means not enough photo layers can be squeezed in for the amount of turning the lens focus. So, I would have to put in on a focus rail.

I have tried to be clear, but I think I have said what I can. If anyone actually has this lens and does focus stacking, glad to hear from you.

And I pointed out that I don't have any lenses that I use for close-work that are not manual. They have no auto-focus, plus evenly electronically, you can't even-step around a sphere, etc. Spheres take more and shorter intervals, and so on.

[David H. Hartman]

I'm guessing but I doubt that the 100mm Leica Elmarit-R Macro is an AF or IF lens. I'll do a search and see what I can find.

I haven't done stacking yet but I'd like to try. I read these threads to learn. When I try my hand I'll start with Nikon PB-4 Bellow and a D800. My best guess is I'll prefer moving the camera while keeping the lens stationary, a method I probably learned by using a monorail view camera back in 1974. I don't Invision using any of my AF-S lenses.

Dave Hartman