View Full Version : Kodak Polychrome graphic arts films
11-27-2007, 11:26 PM
Sorry this is a film question, but I figured this forum was more likely to cross paths with users of such films than the B/W Film forum.
I once ran into someone who had used Kodak Polychrome graphic arts films for contone ULF, but can't remember who.
A visit to the KPC site left me confused with the multitude of products they offer, including recording film, apparently red sensitive.
I believe years ago when I first learned of them they had some green sensitive and blue sensitive hard dot films in huge rolls up to about 60".
Has anyone used any such films for ULF pictorial work instead of intended hard dot use?
11-27-2007, 11:46 PM
I have not used this type of film pictorially for a long time. I think there was a major change in emulsion formulations around 1990 and the subsequent films were extremely high contrast in universal developers. The density with some films I have used would go from base plus fog dmin .01-.04 to dmax of 5+ over a 1 to 1.5 stop range. You would need an extreme compensating developer. I have a 48" roll in my basement but could not make a test until sometime next week if you are interested. I think I would try technidol developer as a starting point.
imagesetter film needs to be very high contrast and needs to have the ability to be developed at a high temp and very fast.
that is what the KPG film is made for. The offset printing industries is what the market for this film is. I you can make it do something else then good luck.
11-28-2007, 03:20 AM
Thanks, Richard & Lee
Maybe either of you can help me.
I know that in general there are a couple of types of high contrast film people have successfully used for normal pictorial work through special developers.
I thought I had run into a green 'ortho' film previously and am trying to find a green-sensitive film that can be made continuous tone in this manner.
I had a hard drive croak and can only rely on my memory: I obtained an Opti-Copy lens and thru writing to someone with the same name as the patent holder (turns out it was his son), my letter was handed to the former optics QC guy at Opti-Copy over lunch. My contact has become as scarce as that old hard drive that contained our email correspondence. I see him post rarely on other forums but all email addresses are defunct.
So, what I learned was the lens was used for hard dot work with pulsed xenon lighting (full spectrum) fitted with green filtration and sometimes an additional yellow filter on the lens. Additionally, definitely a monochromatic lens, not blue-optiized like some of their other models.
So, what I am researching is whether there is still a green-sensitive film for graphic arts work so I can utilize the optimal resolution of this lens. It's apparently good for nothing at other wavelengths and I have enough other doorstops. I'm determined to make some unique use of it and eventually I would like to enlarge reversed b/w negs (transparencies) to large film as mentioned above to contone process and make large negs for contact printing kallitype/argryotype.
So, Richard, yes, that type of film is on my wish list, and the research part is cheap. Unfortunately the film may not be, and regardless of how close Canada is, shipping people see it as a foreign land and charge what they do to enable border crossing.
Anyway, no harm in asking, and eventually I will find something suitable, I hope. Unless I run into a deal I can't refuse, I've recently begun thinking maybe a 12" roll would be a realistic starting point as it's not to big to use in-camera for say 12"x20".
Does such film exist?
11-28-2007, 03:23 AM
BTW, it's the 27" f/8 lens and may have been used on the Imposer machine.
Retailed for $35k however many decades ago. Cost from Corning Tropel in whatever quanitities they bought them was $10k.
11-28-2007, 09:43 AM
IIRC the Imposer was also used for in camera colour separations. One of my customers had one of the high resolution lenses as well. Considering the limited magnification range of the Imposer and the end use of the film, I really wonder if there was much point to using it. I have the head of an Opticopy 8.5 x 11 camera enlarger which has a built in green filter. I have used it with and without the filter and notice no difference. It was built around a 360mm Componon S. I also have a Wild lens which is optimized for the 550nm line of the mercury vapour spectrum. The performance of this lens in white light is phenominal, resolving better than 400 lppm with my microscope. I am about to play with it using Kadak 2430 aerial film that is supposed to resolve 800 lppm. I saw a roll of this on the auction site a few days ago so it is still available at times. It is an ortho emulsion. I would think it better to try something like this than a high contrast film. Try seller mrfoto 1.
11-28-2007, 07:34 PM
You can get Green or Blue ortho emulsion in xray Film. http://www.cxsonline.com
11-29-2007, 01:20 AM
Yes on xray. Thanks.
Not same resolution as graphic arts film, but I wonder for contact printing if it matters much...someone told me equine xray film is available up to 3 or 4 feet but I haven't found larger than 14"x17" yet.
For shooting, I don't think xray film would enlarge well because they seem to be pretty low res. (I've only seen Fuji data for this, and it wasn't really any better than Polaroid prints...6-7 lp/mm. I hoped I was wrong).
That is sounding better as I think about it. Tiling individual sheets of film on a vacuum board and enlarging onto it is another way to afford a large area of film without committing to a $600 (or whatever) roll of film - the inter-sheet lines are ok with me on a large print.
11-29-2007, 02:14 PM
The fact that Xray film has an emulsion on both sides, limits its resolution, because you will always have a slightly out-of-focus image superimposed on the sharp image, creating a slight "glow" to the photo. This can be quite an attractive quality, but not for highest resolution. There is a film made for making copies of Xray images, and this film is coated only on one side. This would be the film to use for maximum sharpness available from Xray materials. The whole reason pictorial photographers use Xray film is because of its tonal rendering (approximating the look of wet collodion photography), and its extreme cheapness when compared to "real" camera films.
sun of sand
11-29-2007, 04:19 PM
One day I'm going to try some IR imagesetting film
11-30-2007, 04:19 AM
Looks like Arista APHS cuts off at about 600 nm, so that should actually work with blue to green.
I've run into two people who have used some of the 'left-field' fims like Imagesetting, one used IR, one used red, IIRC.
The IR worked liek IR but he didn't care for the tonality and didn't pursue it further.