View Full Version : Process lens image quality

Ron Marshall
29-Jan-2006, 09:20
I know very little about process lenses, but I imagine they are optimised for 1:1. How do they perform at infinity?

Dan Fromm
29-Jan-2006, 09:59
Um, to anticipate a little, when Bob Salomon notices this thread he'll tell you that when taking pictures of subjects at distance you're best off using a lens designed to do that. By him, process lenses shot at distance are second-best. I believe that this is Bob's personal view and that it does not reflect his commercial interests.

Nikon's literature on their process lenses (Apo-Nikkor, Process-Nikkor, some but not all Nikkor-Qs) says that they are best from 3:1 to 1:3 and good at all distances.

Rodenstock's propaganda on Apo-Ronars asserts that an AR is better at distance than the equivalent tele lens.

The lens books agree that dialyte type lenses optimized for 1:1 hold their corrections very well at all distances. They suggest that asymmetrical lenses like tessar types optimized for 1:1 should be worse at distance. My Taylor Hobson tessar type copy lenses don't agree with the books.

In my limited experience, process lenses do well at distance. But much depends on condition, and many of them are very hard to put in shutter. Two sets of problems there. The cells aren't always threaded to go into standard shutters, require expensive adapters. And sometimes extracting the cells from their barrel isn't easy. I finesse those problems by hanging 'em in front of a shutter. This works for me because I shoot 2x3, might not always work with larger formats.

If you're contemplating buying a process lens and then putting it in shutter, estimate the costs as best you can before buying. It often turns out that a relatively modern used lens of the same focal length in shutter will cost less.

Brian Ellis
29-Jan-2006, 10:43
I've used four different G Clarons and one APO Artar. All performed well at any distance. It may be desirable for some specialized purposes (e.g. macro photography) to try to match the distance for which a lens is optimized to a particular subject distance but I don't think that's necessary for most purposes. I use whatever focal length lens is needed for the desired composition and never think about whether I'm within the distance for which the particular lens is optimized. There are so many variables involved in making a technically excellent photograph that I don't think they can all be dealt with to perfection. Operator ability/talent/knowledge is IMHO much more important than owning the perfect equipment for every possible purpose.

29-Jan-2006, 11:08
I've seen a lot of work done by friends with process lenses (including older ones like apo tessars and kodak copying ektanons). They seem to make beautiful, crisp contact prints. Looking at negs with a loupe, though, it's clear that at any significant magnification they'd be soft.

If you go to the schneider site and look at g-claron MTF curves, you'll see that they are not sharp lenses (by the standard of general purpose lenses) a higher resolutions or at infinity.

N Dhananjay
29-Jan-2006, 11:47
Yes, many process lenses are optimised for close distances but the corrections of the dialyte design that they are based on are supposedly fairly robust to a wide variety of distances. That is, the corrections are not terribly upset by using them at distances they are not optimised for. In short, while there may be a theoretical drop in performance when you use them at infinty, the drop is not bad and based on practical experience of many, they perform admirably at infinty. Cheers, DJ

Ted Harris
29-Jan-2006, 12:49
I have never done any exact optical measurements of 'process lenses' bu tI use the Fuji A series 240mm and 300mm lens and, like many others, find them among the best lenses in my kit. The 300, particularly, is one of my all time favorite lenses for landscape work. I also use a Docter Apo Germinar 3650mm lens (also a process design) that performs wonderfully at infinity for landscape work.

I think you willfind that most folks have similar experiences.

Ed K.
29-Jan-2006, 13:30
Hey Ted -

Ahem... You have a 3650mm ( 143.7 inch, or about 12 foot lens??? )

This is amazing! I'd like to borrow it from you sometime. Is it faster than f2800?

I'd like to build a nice "tow and shoot" camera for it. How big
is the image circle on it, and does anyone know where to get a 12 foot wide
roll of film made up? <big grin> Perhaps it would be better to just make
some giant tintypes or glass plates...

Tony Karnezis
29-Jan-2006, 14:23
Ed, in my experience the fact that the 3650mm lens is two stops slower doesn't make a difference in focusing on the ground glass. Depth of field, which is limited with the 2800 as you know, is nonexistent with the 3650, so choose your subject carefully. The real problem is that when stopped down to the optimal aperture of f/2680, it doesn't let in any light. But when you see the final results on paper, and when people comment "that single eyelash that's in focus is really pretty," it makes the back surgery for the slipped disk seem like a small price to pay.

But seriously, Ron, I had the same question a while back. I've never seen back to back comparisons of a process lens to a plasmat or other design, but looking at the beautiful prints of Michael Smith & Paula Chamlee, many of which were made with old Goerz Red Dot Artars, and it's clear to me that you won't be disappointed with a process lens for distant subjects. If Bob Salomon is here, could you provide a link to photos taken with a plasmat vs a process lens at low reproduction ratios? That would be great to illustrate the point.

Ted Harris
29-Jan-2006, 15:13
Ed, LOLOLOL ... ahh those cold fingers! Welllll, I'll sell it to you for only 50¢ a mm. A bargain at twice the price ....

Dan Fromm
29-Jan-2006, 15:47
Guys, after I shot my 180/10 Apo-Saphir against my 7"/4.5 Aviar, post-WWII and coated and beautiful, I sold the Aviar. The Aviar is, I've read, legendary for all sorts of good qualities. But understand that for me coverage is unimportant even with lenses as short as those because I stick with tiny little 2x3.

I've reported many times that with the same subjects at 1:2 and ~ 35 feet at f/9, f/11, and f/16 my 210/9 Konica Hexanon GRII shot better than my 200/4 MicroNikkor AIS. This on a Nikon, so all I saw was central sharpness and contrast. There was no contest, the GRII is a much better lens.

In the french LF forum, Henri Gaud wrote "Apo-Saphir Boyer Paris <snip>600 mm F/10 (celui est très bon, je l'utilise encore, a part le cercle de couverture, même niveau qu'un Fuji C, rendu un peu plus chaud)." This one is very good, I still use it, aside from coverage, same level as a Fuji C, rendition a little warmer.

The thread in which he made this remark is http://www.galerie-photo.info/forum/read.php?f=1&i=67974&t=37579 Note that M. Gaud is an apostle of the most modern lenses possible. He has often written that LF lenses from the '70s and early '80s aren't good enough for critical work.

In the end it all comes down to budget and discernment. Those with small budgets and no discernment, like me, can be happy using process lenses as taking lenses at distance. Others may not be so happy.


Kevin Crisp
29-Jan-2006, 15:50
Re: PaulR's comments, I haven't used Kodak copy lenses or APO tessars. The suggestion that negatives shot with G Clarons can barely survive modest enlargement is absurd.

Ed K.
29-Jan-2006, 16:05
Somehow, the html processor made things bold in error.
Let's see if putting in an unmatched unbold tag works...


Eric Rose
29-Jan-2006, 17:10
I have used a Rodenstock 135mm EL for general photographic work and it's performance was outstanding. I was blown away by the sharpness and contrast. However while using it for some night shots with bright lights in the corners I got some real funky halos.

It's not that I have nothing to compare it with as I also use the latest and greatest APO German lenses too.

I think you would be hard pressed to tell the difference between using a process lens and a regular lens during normal photo making exercises.

Maybe the math doesn't agree, but I've not had people look at my photos with slide rules in hand LOL.

Dan Fromm
29-Jan-2006, 17:32
Oh, come on, Eric, slide rules went out when electronic calculators came in.

Thinking of which, does anyone here know the name of the first electronic calculator to come to market? An English device, the ANITA. Used nixie tubes to display the digits. I first used one in, IIRC, 1965.

And does anyone know what ANITA is an acronym for? A New Inspiration To Arithmetic. I am not making this up, the instruction book said so.



Jason Greenberg Motamedi
29-Jan-2006, 18:20
</big> Make it stop!

Jason Greenberg Motamedi
29-Jan-2006, 18:27

Your "big grin" which you typed in brackets got read as HTML code (hence it is invisible). Funny.

I run a middle path with process lenses, but mostly I figure that since I have never done more than a 4x enlargement with 5x7, it really doesn't matter very much. My Apo-Ronars and Apo-Artars and Apo-FourElementWhatnots are just fine. I am a bit less fond of G-Clarons and other 6 element process lenses, but that is mostly baseless prejudice on my part.

Dave Moeller
29-Jan-2006, 19:18
I've had very good results using modern process lenses, enlarging 4x5 negatives as far as 16x20. Not much of an enlargement, but there was no softness to speak of at that modest size. My 4x5 lenses are mostly modern taking lenses with a couple of process lenses thrown in, and I can't tell which lens was used for which shot unless I look at my records.

My mix of 8x10 lenses is very much the opposite; mostly process and a couple of modern shuttered lenses. With 8x10 I only contact print, so I have no way of knowing how the negatives would stand up to enlarging. They look fine under an 8x loupe, which is far beyond what I need out of them.

Bob Fowler
29-Jan-2006, 21:06
Hmmm... I kinda like my process lenses. 12" and 14" Apo Artars for 5X7, and 305mm f/9 Apo Nikkor and 17" f/10 Ektanon for 8X10. Then again, I also like Rapid Rectilinears. Truth be told, my lens arsenal is all over the map!

John Kasaian
29-Jan-2006, 21:48
The APO Artars, Ektanons, G Clarons, Konicas and even an Ilex Process Paragon which I'm familiar with are superb performers. Perhaps it isn't a matter of Process vs. Non Process lenses, but that different makes and models of process lenses do work very well while others may not.

The problem it seems to me is its not nearly so much "the lens" as it is the subject the lens is aimed at. I've yet to see a great photograph mucked up by a less than 'state of the art' lens---many wonderful photographs of the past have been produced using what we'd now consider obsolete glass (of course I wouldn't consider them obsolete!)

If you have a good lens with a good reputation, then good for you. If you have a mongrel lens and you like the results, thats swell too. Don't make your lens into an excuse for any shortcomings in your work---that'll drive you crazy, or at least to the eBay poorhouse ;-)

I doubt if you can go wrong with an APO Artar or G Claron.

Good Luck!

29-Jan-2006, 23:22
I have a 240/f9 Apo Ronar in a Copal shutter and recently shot some material while on holidays in the Yosemite national park.

If anyone in a blind test can identify any lack in the image [apart from my contribution] I would be very surprised. Everything about the near foreground to infinity performance of this lens is remarkable. Despite an aperture of f9 it is still very easy to focus.

The lens has far better performance than me as the photographer :)


30-Jan-2006, 00:15
"The problem it seems to me is its not nearly so much "the lens" as it is the subject the lens is aimed at. I've yet to see a great photograph mucked up by a less than 'state of the art' lens---many wonderful photographs of the past have been produced using what we'd now consider obsolete glass"

remember that people using the old glass knew about its abilities and its limitations, and worked within them. a lot of those old lenses were only good for contact printing ... so that's what they were used for. they may well muck up your results if you shoot 4x5 and want to print 16x20, if you need to use wide apertures, big movements, or a wide range of magnifications. improvements in optics have led us to new working methods and new expectations.

granted, i'd rather see work made by a fuzzy lens than a fuzzy photographer.