Contrast filter specs?

Discussion in 'Contact Printing' started by ntenny, Nov 4, 2009.

  1. ntenny

    ntenny Member

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    I've been doing contact printing on multigrade papers, but just using a light bulb for illumination (I don't have an enlarger, nor the space for one, nor the all-important spousal permission for one). As far as I know, this generally means I'm getting grade 2, which is usually fine. However, I'd like to have the other grades available, which means filters.

    The obvious way to do this, I think, is to get a big gel-type contrast filter and put it on top of the printing frame itself. But as far as I can tell, no one makes contrast filters in a size big enough to do that (I'm mainly printing 9x12cm).

    Of course, I could always get some coloured glass or theatrical gels or something in the proper colours, and there I'd be with perfectly good contrast filters, right? Only I can't seem to find out what "the proper colours" are. Is there a spec sheet somewhere that says exactly what colour a filter should be for a given contrast grade on VC paper?

    Thanks

    -NT
     
  2. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Ilford makes a 6" filter set. You could cover a 9x12cm neg with that, or you could get a 6" or smaller reflector for your lamp and make a gel filter to fit over it. An advantage of using Ilford MG filters, is that they have neutral density built in, so you can go from grades 00-3.5 without having to adjust exposure, and grades 4-5 only need one extra stop.
     
  3. ntenny

    ntenny Member

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    OK, now I feel dumb; I'd discovered that, but I saw "6x6" and assumed it was in cm! :smile:

    Thanks for setting me straight.

    -NT
     
  4. BetterSense

    BetterSense Member

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    I'm poor, so I bought the 3" ILFORD filter set and use it as under-lens filters. About 1/3 the cost of buying the under-lens set.
     
  5. RalphLambrecht

    RalphLambrecht Subscriber

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    Nathan

    You have to put your foot down. No permission to buy an enlarger is a no-go. Get some polysulfide toner and tell her that the smell would not occur if you just had an enlarger! Of course, there is a danger that she will get her stuff an leave you, in which case, you don't need to ask anybody for permission anymore, and you get a lot more room for the enlarger.

    Just kidding.

    Davids idea is a very good one, but the neutral-density capability of Ilford filters is unfortunately highly sophisticated and useless. Not that any other filter does a better job. They all try to satisfy an impractical ISO standard. But go with David's idea anyway. That will work.

    Let me know if you need the recipe for polysulfide toner. :wink:
     
  6. John Koehrer

    John Koehrer Subscriber

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    Wasn't it Brett Weston that used a small box built around a light bulb to hold VC filters beneath the lamp?
     
  7. Rick A

    Rick A Subscriber

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    You could do the obvious, and buy graded paper. There are some excellent ones available from Freestyle that aren't too terribly expensive. I still do a lot of printing on Kodabrom II RC, that I get off of fleabay, in grades 4 and 5. This works great for printing chromogenic negs, and some color.

    Rick
     
  8. Anscojohn

    Anscojohn Subscriber

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  9. ntenny

    ntenny Member

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    You guys are missing the long view here. If I can't have an enlarger, what other options might I have if I wanted to produce, say, nice frameable 5x7 or 8x10 images? Hmm, I bet I can think of a way if I just put my mind to it... :smile:

    -NT
     
  10. RalphLambrecht

    RalphLambrecht Subscriber

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    Nathan

    Get to the root cause. Why can't you have an enlarger if you can have everything else that belongs into a darkroom?
     
  11. Rick A

    Rick A Subscriber

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    I can feel for your dilema, as you would need a large machine to handle 6x12cm negs. You are just going to have to move to larger quarters, and buy an enlarger(right after you buy your spouse a really nice ring) an extra bedroom or bathroom would suffice for the new equiptment(and you if you dont buy her something nice)Also, you must do your part in convincing her of the dire necessity of having an enlarger-especially a large one(at least a 4x5)

    Rick
     
  12. Kirk Keyes

    Kirk Keyes Member

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    Photo Techniques had an article a few years ago - I think my Howard Bond - about using Rosco theatrical gels as VC filters. His article showed it worked well.