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  1. #1
    TheFlyingCamera's Avatar
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    COT-320 and Palladium

    I've been playing around with two different paper types I got with my first ever Palladium kit. I got the Cranes (the big advantage of the Cranes is that it is a much faster medium - the downside is the stuff dissolves worse than generic paper towels when wet) and the COT-320. I have a couple of questions about the COT-320. I notice there are two distinct sides to the paper - one smooth, the other coarse. I have been coating my emulsion onto the smooth side, but my prints seem to still be soft and have too much of a paper texture showing up when dry. Should this be happening, or do I need to do something in addition to avoid this, like re-sizing the paper?

    I've built my own UV lightbox more-or-less - I got six 24" bl-b tubes from Home Depot, and mounted them to the underside of my enlarger table. The lamps are very tight to each other, as I've read about in various descriptions of how-to-build descriptions. I've got the shelf where I put my contact frame about 12" or so from the lamps. It seems like my exposure times are somewhere north of 15 minutes, but I've only had real success in printing using direct sun exposure to date. Do I need to modify my setup in any way to improve my results, or do I just deal with 20 minute exposure times?

    Also, how do you gauge proper exposure under blacklights? I have a decent idea when something is properly exposed using sunlight, as I can see the brown darkening. Any tips at all will be greatly appreciated.

  2. #2
    david b's Avatar
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    where did you buy the palladium kit from?

  3. #3
    Jeremy's Avatar
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    Quote Originally Posted by TheFlyingCamera
    I've got the shelf where I put my contact frame about 12" or so from the lamps. It seems like my exposure times are somewhere north of 15 minutes, but I've only had real success in printing using direct sun exposure to date. Do I need to modify my setup in any way to improve my results, or do I just deal with 20 minute exposure times?
    Why is the contact frame so far away? My frame is only about 3-4" down from the bulbs; I get even lighting and much faster exposure times.
    Let's see what I've got in the magic trash can for Mateo!

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  4. #4
    Kerik's Avatar
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    Quote Originally Posted by TheFlyingCamera
    I have a couple of questions about the COT-320. I notice there are two distinct sides to the paper - one smooth, the other coarse. I have been coating my emulsion onto the smooth side, but my prints seem to still be soft and have too much of a paper texture showing up when dry. Should this be happening, or do I need to do something in addition to avoid this, like re-sizing the paper?
    You shouldn't have to re-size a paper like COT 320. I'd have to see a print in person to answer your other question. Have you seen pt/pd prints up close and in person before? If so, do these look different? How are you coating the paper?

    Quote Originally Posted by TheFlyingCamera
    I've got the shelf where I put my contact frame about 12" or so from the lamps. It seems like my exposure times are somewhere north of 15 minutes, but I've only had real success in printing using direct sun exposure to date. Do I need to modify my setup in any way to improve my results, or do I just deal with 20 minute exposure times?
    20 minutes is on the long side, but first tell us about your negatives. (FYI, I use FP4, HP5, and Forte films processed in Rollo Pyro. My negs usually print in 6 or 7 minutes or less under a bank of 40W BL tubes.) Also, you can move the contact print frame much closer to the bulbs (2-4 inches). Your times will be shorter, but maybe not as much as you'd expect. The inverse square law doesn't apply to a large bank of lights, it applies to a point source.

    Quote Originally Posted by TheFlyingCamera
    Also, how do you gauge proper exposure under blacklights? I have a decent idea when something is properly exposed using sunlight, as I can see the brown darkening. Any tips at all will be greatly appreciated.
    Why not just pull the frame out from under the UV and turn on the room lights?

    Good luck. You're on your way...

    Kerik
    www.kerik.com

  5. #5

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    Sounds like you have your print frame too far from light, 12 inches is pretty far. Use test strips to determine exposure time. Cot-320 should be pretty smooth, how are you coating? Sometimes too much brush work can raise the nap or fibers of the paper.

  6. #6
    colrehogan's Avatar
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    Quote Originally Posted by wm blunt
    Sounds like you have your print frame too far from light, 12 inches is pretty far. Use test strips to determine exposure time. Cot-320 should be pretty smooth, how are you coating? Sometimes too much brush work can raise the nap or fibers of the paper.
    The same thing can happen if you've moved your coating tube across the paper too many times.

    Also, have you dried your paper thoroughly after coating it?
    Diane

    Halak 41

  7. #7
    TheFlyingCamera's Avatar
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    Many thanks to all...

    I'm coating with a puddle pusher. I got the 12" distance from some reference on how to build the lightbox. I can move the shelf for my contact frame much closer. Negative-wise, I'm shooting FP4+ (or Arista 125 in 8x10, which I assume is the same animal in a different label), processing in PMK Pyro, when printed on silver paper, they are printing somewhere between a 0 and a 1 for grade (55 yellow filtration on my dichro head).

    I think the paper is dry enough before printing - it feels dry to the touch on both sides, and I'm drying it with a hairdryer.

    I got the palladium kit from Bostick & Sullivan.

    I just got a new contact printing frame from Photographers' Formulary, and a smaller puddle pusher to coat some for 4x5 negs. I'll try moving the shelf for the printing frame a lot closer to the bulbs and see how it goes.

  8. #8
    TheFlyingCamera's Avatar
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    Ok -

    I moved the contact frame to about four inches from the lamps - I'm still getting long exposures (15+ minutes) but I'm getting much better dmax on my prints, and an overall better print. Here's an example... I do have a question though- is this much graininess in the print normal? Or is this just something I'll find on a negative-by-negative basis?

    http://www.theflyingcamera.com/photos/JStreeLEBSF.jpg

  9. #9
    colrehogan's Avatar
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    The graininess could be because the paper isn't completely dry. I know, you think your paper is dry. I've thought that some of my papers were dry, but they came out similarly to yours and there's not that much grain visible in my negative (at least not visible to me). How long are you drying your paper?

    See the sky in this picture: http://dianemaher.fotopic.net/p11879189.html
    Diane

    Halak 41

  10. #10
    TheFlyingCamera's Avatar
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    I'm drying it for about 5-10 minutes with a hair dryer. I let it sit a bit first, then hit it with the hair dryer. I hit it from both the front and the back, alternating sides.

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