Perhaps someone can help me out.
I just acquired a 70mm back for my 4x5 and have come across some attractive offers on slightly dated dupe films.
OK.. explain to someone who's a bit sleep deprived. What sort of results do you get from using a dupe film as your original?
Although this isn't the color forum I'll ask the same question for color film.. What's the difference?
I would assume a dupe film would be tuned for a flat response, low grain, etc.. but it seems to me a possible way of shooting a lot of film quite inexpensively.... unless I'm dramatically mistaken ;)
Thanks in advance for any perspective, advice or experience.
It's hard to answer your question based on the information provided. Will you be using the film for its original purpose--copying old black and white photos? Duplicating films vary in their spectral sensitivity and often react quite differently to different developers. Kodak Commercial, my favorite for copying, is sensitive primarily to blue, and I usually rate it at about E.I. 8 under photofloods, processed in HC-110B for 2-3 minutes depending on the contrast present in the original and/or the final result desired. The daylight E. I., however, is 50; I've never tried it as a pictorial film, but I imagine that the results would have an old-time rendition similar to the emulsions used back in the 19th century. Another film, Kodak Ortho Copy, which I believe was available in 70mm, has a rating of 12 for tungsten and 25 for both White-Arc Flame or Pulsed-Xenon. If you can identify the particular type of film you have, I'll bet that someone out there in APUGland can provide specific exposure and development data.
Otherwise, you'll just have to do a little experimenting, but, hey, that can be interesting too.
In my Kodak catalog black & white duplicating sheet film ( 4168 ) is a direct positve product that produces duplicate negatives when contact printed from your existing negative. I think you are correct to assume that the image will be very fine grain and have lower contrast than a camera film. Film speed is not specified.
I used some Ektachrome duplicating film years ago in a 35mm camera and the result was a very soft color rendition. That product was ASA 16 for tungsten.
P.S. There is a big difference in COPY film and DUPLICATING film. Copy film produces a negative. Duplicating film duplicates the original.
GMA--Thanks for pointing out the distinction between duplicating and copy films. The second line of my previous post should use the word "copying" instead of "duplicating."
i've used negative duplicating film - it used to be called SO-132.
kodak doensn't make anymore, but you can get the exact same thing for 1/4 the price kodak used to charge from photo warehouse.
it is about the same speed as azo paper.
there is a blue cast to the end product after it is "souped" in paper developer.
i've thought of making camera negatives with it, but the all day exposure kind of kept me away. :)
the upside is that since it goes from negative to negative ( single step ) you don't have to deal with an internegative. the downside is that it is kind of flat, there is a loss of information, and it is slower than you would expect.
hmm, a nap makes everything a little bit clearer :)
Thanks for the replies!!
I don't plan to use the films for duplicating, I'm looking for something that will be inexpensive to pump through the camera in volume and have an interesting look to it.
My biggest concern is getting enough speed since I'm primarily looking for a film I can use handheld.
The film I could find the least data on is: 2421 AEROGRAPHIC Duplicating 2421 (ESTAR Base) (b/w).
A 19th (turn of the century) look might be really cool!
I'm not opposed to ordering a 100' of tri-x. I'd never really thought of using oddball films before and the idea rather appeals to me.
Please refer to my earlier reply. If you use DUPLICATING film in a camera you will not end up with negatives. You will have low contrast positives (transparencies). I suppose you could then contact print the positives to a lith process negative film, but it will be a lot of extra effort and expense to get a negative. Why not use negative film in the first place? If you want an old time look just use an orthochromatic COPY negative film in your camera.
Thanks for your two posts. :)