PDA

View Full Version : Ilex Paragon 7.5 in f/4.5: fit for color work or not?



Philippe Gauthier
21-Feb-2004, 08:35
I own an Ilex Paragon 7.5 inches, f/4.5 lens (serial #4422) that I bought only with B&W work in mind. I've been satisfied with it so far. I now have an opportunity that would require me to use color transparency film, but I'm not sure I can do the job with the lens (the other one is so ancient and little known that the question isn't even worth asking). What do you think? Is this apparently uncoated lens made in the late 1940's sufficiently corrected for color aberrations to be used with color film?

The design, as far as I know, is a relatively contrasty Tessar type. Will the contrast inherent to the design compensate for the relative lack of contrast caused by the lack of coating? Or should I use a very contrasty film (Velvia 50, for instance) as some form of compensation? But then, the wild colors of Velvia 50 on a lens not designed for color might just be too much...

Any opinion? I'd rather lose the (small) opportunity than buying a more modern lens. I'm saving for an old 8x10...

Ted Harris
21-Feb-2004, 09:52
If I had a choice I'd go with a more modern lens. OTOH your Ilex was good enough for color when it was new and I was a young photographer so it should be good enough now. I say that with the reservation that good enough is not as good as it can be ... buy ten sheets of film and try it out.

Tony Galt
21-Feb-2004, 10:03
Why not rent a more modern lens for this project? (That, of course, assumes that you are located near some outfit that rents out large format lenses.)

Philippe Gauthier
21-Feb-2004, 10:18
Tony: Renting would be a good idea - and yes, it is easy to do where I live. But the project is a two week trip; renting for a day is OK, but two weeks would simply be prohibitive - probably more expensive than a second hand modern lens + shutter.

Ted: Thanks for the bit of lore. Knowing that it is indeed designed with color in mind - even if it's not optimal - is already half the answer. Testing is the obvious answer, but everything here is under 2-3 feet of snow, almost monochrome; and the actual pictures would be shot in lush and green Ireland. There is no way I can realistically test for that right now!

Dan Fromm
21-Feb-2004, 12:03
Philippe, reasoning by analogy -- my uncoated 101/4.5 Ektar makes nice color transparancies when I get the exposure right -- you have nothing to worry about. And you believe you're stuck with the Ilex anyway.

I worry more about metering and off-speed shutters, both of which are real problems, than about a lens' characteristics. My lenses, like yours, are what they are and I can't do anything about that. But I can certainly meter badly and from time to time a shutter that I thought was ok betrays me. So I try to meter well and to make sure my shutters do what's expected.

Cheers,

Dan

Robert Brown
21-Feb-2004, 12:09
Hi Philippe

I asked Steve Grimes the same question (when he was still with us) a couple of years ago. I shoot transparency film and asked him if the older lenses (such as the Ilex Paragon) have adequate coatings to produce color corrected images, and what follows is a direct quote from his reply:

"Yes. It is a common and persistant piece of misinformation that optical coatings are somehow related to Color Fidelity and Color Correction. They are not. Speficically, "Color Correction" is a parameter of lens design which involves selection of the glass and design of the curved spherical surfaces so that all the colors focus at the same (or as nearly the same as practical) place on the film. It is not in any way connected or related to Optical Coatings. "Color Correction" long precedes optical coatings and was acheived some fifty years before the introduction of color film. Black and White photographs taken with a poorly color corrected lens are blurry, so color corrected lens design is equally important in black and white photography as it is in color photography.

"Optical antireflective coatings (there is no such thing as "Color Coating") have to do with enhancing the transmission of white light (made up of all colors) thru the glass. They help prevent the reflection of light from air to glass surfaces. A lens with no coatings, made of clear optical glass will, by definition, produce the best color fidelity. Well designed optical anti-reflective coatings will cause the light to be conducted throughout the spectrum and not interfere with the transmission of any partcular range of colors.

"Since optical internal reflections and light scattering are minimized in optically coated lenses they tend to produce images that are more "snappy" and/or contrasty and yeild a more modern presentation."--S. K. Grimes, 24 April 2002. Oh, that dear Steve was still alive--he was a sorce of great information and inspriation. His company is still in business and his technicians can be reached at www.skgrimes.com. They are very helpful and love to disperse their knowledge.

In short: the Ilex can and will do the job. But if your project is critical (most are) you may want to first shoot a few sheets of Velvia (or what ever you plan to use) with the Paragon and put the results on the light table. A few sheets of test film can be cheaper than getting a new Schneider or Fuji or the like, and it will tell you what you want to know. Hope this helps. Bob

Philippe Gauthier
21-Feb-2004, 12:46
Thanks a lot, Robert. I knew that coatings had little relation with color (more with contrast), but I didn't know that color color correction was important even in B&W.

There is no way I can test the film in a realistic setting, but I think I'll just take the risk and buy a few sheets. I'm used with Velvia in 35 mm and anyway, the opportunity is sight is more speculative; they'll buy it if it's good, but they aren't waiting for it. So it's not catastrophic if the colors are so so or the exposure a bit off on some frames.

Dan got me a bit worried with his shutters, but my results in B&W are consistant so they should be with slide film, too.

Bob Fowler
21-Feb-2004, 14:13
Have you considered getting a Polaroid holder and film to do some testing? Even a 405 holder and 690 pack film will work fine to help dial in exposure (Fuji FP100C is my fav).

Philippe Gauthier
21-Feb-2004, 15:12
Yes, I have a 545 holder and I've run some type 54 in it. I'm fairly confident that under 1/25, the times are correct within a 1/2 stop margin of error. I haven't used the higher speeds with Polaroid film.