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Peter Hruby
4-Jan-2005, 10:39
Hello,

I do have one dummy question here. What is the difference between Regular Lens and Process Lens? I know about shutter issue. Can vs Can't be mounted on shutter, but what are other drawbacks or benefits? Price, Sharpness or anything else?

I am so ashamed to put this into forum but it might help me to understand it so I am asking...
Thanks for responses.

Peter Hruby

Ted Harris
4-Jan-2005, 10:55
Process lenses. by definition are optimized togie their best performance when capturing images from flat objects (e.g. art, newspapers, etc.) and they are generally optimized to give their best performance bwtween 1:1 and 1:5. Nonetheless many 'process' lenses give superb performance at normal distances and with normal three dimensional subjects (e.g. G-Clarons, Ronars, Fuji A) and are often among the best in their respective focal length for regular landscape use.

So called 'regular' lenses are optimized to give their best performance at reproduction ratios of 1:5 and beyond and focused at (or near)infinity. Today, most are also apochromates although that was not the case 20 or so years ago.

Mark Sawyer
4-Jan-2005, 17:24
One drawback to *some* (not all) process lenses is focus shift. This means that after you focus with the aperture wide open, then stop it down for the negative, the focus shifts slightly. One more thing to remember and risk goofing up... I have a 480mm Ronar which doesn't do that, but I checked around before buying it to make sure I wasn't going to have to deal with it. I'm quite happy with it as an 8x10 "taking" lens, and since it stops down to f/256, I don't have to worry about a shutter. (One mississippi, two mississippi...)

Another drawback could be that most process lenses are relatively dark; f/9 or 11 or so for max aperture. I can deal with it with a good loupe.

Paul Fitzgerald
4-Jan-2005, 19:43
Hi there,

Just to confuse you more, there are process lenses that are optimized to 1 spectrum of light. Some were designed for U.V., other were for sodium vapor light.

If you are looking at process lenses it's helpful to stay with familiar names.

Just a thought.

Herb Cunningham
5-Jan-2005, 07:01
Following my motto of "nothing in moderation", I got a 'new' Nikkor 455mm f 9 apo from Andy Glover a couple of years ago, had Grimes mount it in a copal #3, and can report it is probably my sharpest lens for landscapes, although it is pretty long for 4x5- if you stay with the name brands, you will be ok. the counterparts, ie Nikon 450 M, which are usually already mounted in a shutter, are actually cheaper by the time you pay for a shutter and pay
to have it mounted.

John D Gerndt
5-Jan-2005, 17:14
The reason anyone is talking about process lenses at all is because they are real cheap. They are real cheap not because they were origanally cheap to make or buy but because of the drastic change in printing technologies. They are being dumped on the market and worse, I almost have to cry when I think of how many of these fine lenses are in landfill as we speak because the businesses clearing out their old equipment never found a buyer.

I have bought perhaps ten of these lenses and have found it possible to back or front mount a shutter for their use with a modicum of woodworking skills and one #5 Ilex universal shutter. I highly recommend you give a few a try. You can get some really fine results for under $100 and many times under $50! per lens.

Technically, they are designed for reproducing 1:1 at f22 and usually have a very narow field of view (40-55 degrees). They are usually single coated. They can be pretty heavy. They are hard to find in shorter focal lengths. I recommend the Konica GRII and Kodak lenses for price and more generous angle of view. Wollensak porcess lenses also go for cheap, but I have not used any of these so cannot speak for their performance.

Cheers,

Ernest Purdum
5-Jan-2005, 19:41
There are two "families" of process lenses. The first, of which the Goerz Artar is a good example. was designed for use on huge horizontal process cameras. There was no need for wide coverage, and they didn't provide it. The Artar has a 46 degree field. Most of these are symmetrical, which is important if the lens is to be used for general photography. Many are a four individual element "dialyte" construction, a type very tolerant to varying subject/image size relationships. (p)

In about the early 1960's, compact vertical process came in for the benefit of small local printing shops. These demanded a wider field lens and several became available. A typical example is the Schneider G-Claron (only the "G" series, Clarons with other prefix letters are very specialized and should be avoided for most purposes). Schneider rates the later G-Claron kenses at 64 degrees when stopped down to f22. Most of these later type process lenses have six elements, needed to gain the extra width. (p).

The later type lenses are not necessarily the best for everyone. The narrower angle types make great "long" focal length lenses if you have enough bellows capability. They can often be front-mounted to a shutter at much less expense than having one of the later type adapted to a shutter. A few of the later type lenses, one being the G-Claron, have cells made to screw right onto a shutter.