Process Lens & Close Work

[neil poulsen]

I read where a process lens is optimized for 1:1 photography with a likely aperture setting of f22. At this magnification, the subject matter is about two focal lengths away from the lens.

I'm wondering, how many focal lengths away must be the subject matter, before a standard lens (versus a process lens) will get effectively the same result?

Put another way, at what magnification does a process lens become advantageous, versus a standard lens?

[Drew Wiley]

Depends. Better process lenses tend to be 4-element air-spaced symmetrical lenses versus the tessar style typically used for cheaper ones. So some of these, like my 4-element Apo Nikkors, are going to be very precise all the way from 1:1 clear out to infinity, and probably pretty good at even slightly greater magnification than 1:1, in other words, quite a bit better than general purpose photography lenses. And at least the series I work with is stunning sharp and well corrected by f/11 down. The f/22 standard is for sake of a printing industry common-denominator specifications, as does not condemn performance at other apertures.

Now, as per you actual question, there's no way to answer it, because you haven't told us yet exactly which "standard" shooting lenses you have in mind. They differ. Some of my own "standard" view lenses happen to be close-range corrected Fujinon A's and Schneider G-Clarons, which themselves perform excellently at infinity clear down to near-macro, at least stopped down a bit. But most general purpose LF lenses don't do so well really close up. And some, like the Nikkor AM series, are designed for only close-up.

[r.e.]

The lens designer/manufacturer may have a recommendation on this. For example, Schneider-Kreuznach recommends that its 150mm Super-Symmar XL not be used at a magnification ratio of more than 3:1. For greater magnification, it would recommend a macro lens. As you probably know, there have been many discussions on the forum about whether macro lenses have advantages over process and standard lenses. In my case, I would follow the recommendation and use Nikon's Nikkor 210mm AM ED Macro lens instead of the 150mm Super-Symmar XL. It isn't relevant to your post, but this would also buy me a bit more working room.

[Dan Fromm]

I read where a process lens is optimized for 1:1 photography with a likely aperture setting of f22. At this magnification, the subject matter is about two focal lengths away from the lens.

I'm wondering, how many focal lengths away must be the subject matter, before a standard lens (versus a process lens) will get effectively the same result?

The same.


Put another way, at what magnification does a process lens become advantageous, versus a standard lens?

This is an entirely different question. It depends on the "standard lens." There is no broadly applicable rule of thumb.

Drew, tessar type Apo-Nikkors have exactly as many elements as dialyte type Apo-Nikkors. I don't know whether the tessar types do as well at distance as the dialyte types do, never had any. I have, though, three TTH process tessar types, one badged Apotal, one badged "Cooke Copying Lens" and one engraved "Copying." All are, contrary to expectation, pretty good at all distances.

[Drew Wiley]

Dan - it's not the number of elements which counts, but the configuration and underlying application. 4-element process lenses are SYMMETRICAL. Budget style process lenses like for "Stat" copy cameras, were generally not. There are of course exceptions, like the very expensive Apo El Nikkor series - too expensive for any typical commercial copy application! But even regular Apo Nikkors were quite expensive when new. Now they're a bargain on the used market. But cheap lenses like Rogonars, once bundled with stat cameras under Beseler private labeling, are now sometimes sold as discount "student grade" enlarging lenses. Some of these are only 3-element.

But again, we don't yet know in this case the exact intended application. Taking close up pictures of flowers? - or of the eye of some insect on a petal of that flower?

[Dan Fromm]

Drew, not to quarrel too much, but tessar type process lenses have 4 elements and are quite asymmetric. I agree with you completely that dialyte type process lenses such as Apo-Artars, dialyte type Apo-Nikkors and Apo Ronars have 4 elements, are symmetrical and are very good at all distances. That they didn't drive tessar types from the market suggests that they were pretty good. I'm thinking of CZJ Apo-Tessars, which were eventually replaced by Germinars, and TTH Apotals. These were made in focal lengths more than slightly too long for "stat" cameras.

[Drew Wiley]

How on earth can any tessar formula be classified as symmetrical? The front group and rear group don't match! Note that I'm not criticizing older non-dialyte process lenses. I have a superb old single coated Zeiss f/9 apo tessar process lens that I love for its out of focus "bokeh" rendition. It does great at infinity too. But it's certainly neither as versatile nor precise as the more expensive later Apo Nikkors. And that distinction becomes critical when moving from general photography applications to downright nitpicky ones, like making precise enlarged internegs or interpositives in the lab.
Or, for a person I know who uses Apo Nikkor dialytes for extreme telephotography using small SLR cameras, it's also an important distinction. I don't use these for general photography myself because I'd need to put them in shutter, and that would compromise the overall weight and practicality of them. But I do have them on Sinar boards for sake of visual comparisons using a view camera, as well as for sake of enlarging application on a big enlarger of mine which accepts Sinar boards.

But as far as branding, that's a whole different game. Sometimes lens names get re-attached over time to relatively unrelated configurations. It's no different in industrial optics. But those CZJ Apo Tessars were not symmetrical; they were tessars. Apo Germinars were symmetrical, but by the same token, were NOT tessars.
They probably also cost way way more than the Apo Tessar option.

[ic-racer]

In my experience process lenses excel when the subject is flat, as in copy work, or using them for enlarging. For a picture with a central object with, perhaps, a blurry background, a conventional lens works very well for me at close distances.

[Dan Fromm]

How on earth can any tessar formula be classified as symmetrical?

I think we agree on something. Please read the first sentence of post #6 above.

[neil poulsen]

. . . Now, as per you actual question, there's no way to answer it, because you haven't told us yet exactly which "standard" shooting lenses you have in mind. They differ. . . .

That's a good point. :o

While I would consider something else, I was thinking of a 210mm G-Claron as a process lens, and definitely a Plasmat (the only other lenses that I have) in the same focal length as a "standard" lens.

I have it in mind to photograph a violin in vertical, frontal position, straight on and across using a 5x7 camera with no movements. I would enlarge either to 11x14 or 16x20. I would like to see every tiny spec of detail on the front of the violin.

[Oslolens]

That's a good point. :o

While I would consider something else, I was thinking of a 210mm G-Claron as a process lens, and definitely a Plasmat (the only other lenses that I have) in the same focal length as a "standard" lens.

I have it in mind to photograph a violin in vertical, frontal position, straight on and across using a 5x7 camera with no movements. I would enlarge either to 11x14 or 16x20. I would like to see every tiny spec of detail on the front of the violin.If that is your goal then it won't matter when using f22-f22 1/2. But going closer to 1:1 it will make the G-Claron shine, while if you try to shoot wide open the plasmat will shine - my Apo-symmar 210mm was so sharp in center it did match my 35mm lenses, while my process lenses do not show super sharpness before f11-f16.

https://www.flickr.com/photos/47052585@N06/albums/72157634939838558 at the bottom has 1:1 pictures comparing 210mm of single-coated Fujinon-W, Nikkor-W, Apo-Gerogon f9 and a Macro-Sironar-N 210mm macro-on-mirrorless shots, done just to educate myself.

Sent fra min SM-G975F via Tapatalk

[r.e.]

I have it in mind to photograph a violin in vertical, frontal position, straight on and across using a 5x7 camera with no movements. I would enlarge either to 11x14 or 16x20. I would like to see every tiny spec of detail on the front of the violin.

A full size adult violin is about 23" long. With a 5x7 sheet of film, and without taking into account the background, you're at a magnification of 4.6:1 (landscape orientation) or 3.3:1 (portrait orientation) just for the violin. You're more or less at the magnification ratio of portraits of people. A standard lens should work fine.

[neil poulsen]

In fact, I'd be using a 180mm Apo Symmar, which has plenty of image circle for 5x7.

This has turned into quite a helpful thread. I appreciate the responses that have been offered.


If that is your goal then it won't matter when using f22-f22 1/2. But going closer to 1:1 it will make the G-Claron shine, while if you try to shoot wide open the plasmat will shine - my Apo-symmar 210mm was so sharp in center it did match my 35mm lenses, while my process lenses do not show super sharpness before f11-f16.

https://www.flickr.com/photos/47052585@N06/albums/72157634939838558 at the bottom has 1:1 pictures comparing 210mm of single-coated Fujinon-W, Nikkor-W, Apo-Gerogon f9 and a Macro-Sironar-N 210mm macro-on-mirrorless shots, done just to educate myself.

Sent fra min SM-G975F via Tapatalk

[Tin Can]

Please define 'close work' exactly

When does normal become Macro andor close work

Ken Lee is a master of typewriter keys, what is that called

Is there a rule?


A full size adult violin is about 23" long. With a 5x7 sheet of film, and without taking into account the background, you're at a magnification of 4.6:1 (landscape orientation) or 3.3:1 (portrait orientation) just for the violin. You're more or less at the magnification ratio of portraits of people. A standard lens should work fine.

[r.e.]

Please define 'close work' exactly

When does normal become Macro andor close work

Ken Lee is a master of typewriter keys, what is that called

Is there a rule?

I didn't even use the term "close work", and I addressed your questions in post #3. I would have thought that what I said in the post to which you're responding (#12) is self-explanatory.

[Tin Can]

Thank you

I will be using for the first time a Nikkor 210mm AM ED Macro

I have used Plasmasts at +3 on 11X14 some years ago and was blasted universally by Forum experts








I didn't even use the term "close work", and I addressed your questions in post #3. I would have thought that what I said in the post to which you're responding (#12) is self-explanatory.

[Drew Wiley]

G-Claron plasmats, generally in no. 1 shutter, were deliberately marketed for closeup tabletop photography, and are excellent for general shooting also, clear out to infinity. Not fully equal to Apo Nikkor process lenses in my own tests, but plenty good enough for most closeup purposes, and more convenient. And a 210 GC easily covers 5X7 stopped down, even at infinity. If one is commercially specializing in big enlargements of diamond rings or insect portraits, then a specialty lens like the 210 Nikkor AM ED might be a worthwhile investment. Otherwise, the specially close-range corrected (but also highly versatile) plasmats like GC and Fuji A series will do a decent job if you want something already in shutter. I've done high resolution 1:1 work with the 360 Fuji A on my 8x10, as well as with the 180 A on 4x5 format.

[Tin Can]

https://www.bhphotovideo.com/c/product/459342-DEMO/Nikon_Macro_210mm_f_5_6_Nikkor_AM_ED.html/specs?gclid=CjwKCAiAyPyQBhB6EiwAFUuakru-A-FC1tJXXfG16NOygwWavGPppLJ0JK3Rm-gHD9Jx_OvJFs7ZuBoCD1MQAvD_BwE

https://www.kennethleegallery.com/pdf/Nikkor_LargeFormatLenses.pdf

[Bernice Loui]

APO artar, APO ronar and similar has been the table top and "close up" image lens of choice for decades. They do excellent from infinity focus to life size 1:1.

The more pressing need for close up images, lighting, camera support/set up stability. Lighting is always an issue for these images as is camera stability/set up. Weaknesses in camera support and set up negates any advantage the the lens might have if stuff does not stay put.

Other pressing question becomes DOF/F, unless stacking of properly focused images is used, DOF/F can be a real issue. Stopping the lens down to f90 or more is not always the cure for this way of nature.


Bernice

[ridax]

My practice-based opinion is here: https://www.largeformatphotography.info/forum/showthread.php?133358-2024-quot-enlarger&p=1394698&viewfull=1#post1394698

But that's all about the purely technical stuff such as sharpness and contrast. And as I said more than once, for 3-D subjects, the out of focus rendition is far more important for me. So for anything 3-D I just use Dagors.

[ridax]

for anything 3-D I just use Dagors.

Or even Half-Dagors when the background is really far away (https://www.largeformatphotography.info/forum/showthread.php?163832-Protar-Lenses&p=1623018&viewfull=1#post1623018)...

[Drew Wiley]

What does a dagor formula have to do with a 3d look? I've generally found dagors quite disappointing with respect to out of focus rendition, and not very good at extreme closeups either. But perhaps you are referring to a particular dagor construction process lens, ridax? They do render what some people have called a subtle bit of "roundness" to edges, for lack of a better way of describing it.O That's one of the reasons I still keep on hand a 14 inch dagor myself for 8X10 usage (but never use it for close-ups per se). Please re-elaborate your specifics in the context of this particular thread.

When I want really lovely background blur at the same time as good close range performance, I resort to an equivalent focal length 360 f/9 single-coated Zeiss process tessar. Someday I need to get that mounted into a Copal 3s shutter for greater convenience.

[ridax]

What does a dagor formula have to do with a 3d look? <...> But perhaps you are referring to a particular dagor construction process lens, ridax?

(1) I am not talking about any '3d look' (which sounds quite a bit mystically, and I always strictly avoid anything non-scientific). I am talking about the out of focus background rendition in 3-D subjects.

(2) I am not talking about a dagor formula. The formula has a lot of implementations very different in their spherical aberration (SA) character. And its the SA that makes the out of focus rendition different. In particular, I am referring to the Series III Dagors and their descendants - the f/6.8 ones (f/7.7 if longer in the focal length) .


I've generally found dagors quite disappointing with respect to out of focus rendition

That may just be the case which is usually described by the words tastes differ. But its also possible that you mean the foreground out of focus rendition, not the background one. If that's the case then I totally agree with you. And besides that, the Dagor's background out of focus rendition gets nice when the lens is stopped down at least to f/10 and stays as fine up to at least f/32. At f/45 it is still good but less good than at f/32. At f/64, it's already nothing special. And it's plane ugly wide-open. The Dagor's foreground out of focus rendition is terrible at any f-stop.

In fact, the topic of the OOF and the SA (not particularly in the macro range; but it's exactly the same in close-ups and in the more distant subjects - except that in close-ups, there are way more chances to have anything out of focus in the frame) was discussed here a lot over the recent decade so I really don't want to repeat all the same again. (I'll probably find the links to the previous discussions containing my own posts on the topic and post the links here when I have time to.)


When I want really lovely background blur at the same time as good close range performance, I resort to an equivalent focal length 360 f/9 single-coated Zeiss process tessar.

I move my f/9 Apo-Tesar-type and the process Celor-type lenses' front elements about 1mm or 2mm out to get a better out of focus background rendition (the pre-WWII Zeiss and all the LOMO barrels allow for that kind of movements easily; the later GDR-era CZJ ones, as well as the post-WWII barrels from lots of other manufacturers, do not). But the front element displacement makes the out of focus background rendition good from wide-open to about f/16 only. At f/22 the influence is already negligible.

What is nearly unique to Tessars and Celors is that a little modification of the barrel makes moving the front element a bit backwards possible. That builds up some positive SA in the outer zones of the pupil which make the foreground out of focus rendition look pleasant wide-open (but alas, stopping the lens down eliminates the effect).

[Drew Wiley]

Interesting. Thanks for the reply.

[Bernice Loui]

225270

Circa 1990's
~240mm APO (red dot) Artar @f22 in barrel round iris, nearly life size or 1:1, 13x18cm Agfachrome RS100, 5x7 Sinar C with Sinar shutter.


Bernice

[Tin Can]

My male Pug, Cosmopolitan Topper loved that flower fragrance

As did my wife and even me...

Our 2 female pugs didn't care, they were a bit mean

Cosmo loved child smell, and ran to them

I bought well used rag dolls from parents, best if never washed

Only hunger got him away, then I had to hide them high up


225270

Circa 1990's
~240mm APO (red dot) Artar @f22 in barrel round iris, nearly life size or 1:1, 13x18cm Agfachrome RS100, 5x7 Sinar C with Sinar shutter.


Bernice

[Bernice Loui]

Not LF, another pix of this flower.

225282


Bernice





My male Pug, Cosmopolitan Topper loved that flower fragrance

As did my wife and even me...

Our 2 female pugs didn't care, they were a bit mean

Cosmo loved child smell, and ran to them

I bought well used rag dolls from parents, best if never washed

Only hunger got him away, then I had to hide them high up