Using a contact print frame for UV expousre of Imagon plates.

I'm wanting to make a portable UV exposure unit for my ImagOn plates. I was considering using a contact print frame to hold the plate and transparency together. This would be instead of a larger, heavier, and more costly vacuum frame.

Will this method work? I know contact print frames are used for solar plates and of course for photo contact printing, but there is always the issue of "light leak" with photo-polymer films if there is not good enought contact between the plate and transparency.

Best, David.

g'day free

why not just try using the equipment you have on hand?

Ray

read the post

Ray, I don't think you read my post very well. I want a portable unit which I don't have on hand. In fact I have no UV unit "on hand."

Ray Heath said:

why not just try using the equipment you have on hand?

Click to expand...

ok free

so you get a piece of 6mm MDF, cut it to the same size as a piece of picture frame glass, 10"x12" is good, then cut the MDF in half cross ways, tape the two pieces back together, two fold back clips either side and one on each end and you have a split back contact printing frame to place in sunlight or under a UV array

simple, cheap, effective, portable

Ray

using a contact print frame for UV exposure

Okay Ra, thanks for info. on how to build one.

I'm still needing some feedback on using one for UV exp. of ImagOn plates. All the conventional wisdom seems to be that I can't use one since it won't give good enough contact between the plate and transparency and that's why everyone uses a vacuum UV unit.

d.

hey free 'conventional wisdom' tells lots of people to do lots of things they don't need to

Ray

Take this with many grains of salt because I have no flipping clue what either of you are talking about, but how about putting a small amount of water between the transparency and the plate and then pressing (perhaps brayering?) them together. The contact should be greatly improved and it'll stay so for a very long time.

Disregard if it's idiotic

keithwms said:

Take this with many grains of salt because I have no flipping clue what either of you are talking about, but how about putting a small amount of water between the transparency and the plate and then pressing (perhaps brayering?) them together. The contact should be greatly improved and it'll stay so for a very long time.

Disregard if it's idiotic

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Idiotic is an understatement Keith.

Don Bryant

Thanks Don.

I have been getting very cocky and brilliant lately; this brings me back down to where I belong.

keithwms said:

Thanks Don.

I have been getting very cocky and brilliant lately; this brings me back down to where I belong.

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Keith,

I wasn't trying to put you in your place, merely trying to alert you that this idea is as you said idiotic. Be careful about things you suggest online as some people may take them to heart. You should know that dry film and water don't mix when printing, especially contact printing.

Don

Fine, then use immersion oil. Or glycerin.

I agree that people should be careful when they stray too far from the textbooks.

keithwms said:

Fine, then use immersion oil. Or glycerin.

I agree that people should be careful when they stray too far from the textbooks.

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Keith are you trying to pull my leg? Contact printing isn't rocket science, there is no need to make it complicated.

Don

I don't know about the characteristics of ImagOn plates, but for photographic processes involving negatives and paper, split-back print frames with heavy leaf springs on the back are good for prints up to about 11x14". Avoid the type of frame that has spring clips around the perimeter of the frame. Vacuum frames become more attractive for larger sizes. This may be where the conventional wisdom is coming from--there is some size at which a spring back doesn't provide good enough contact, and perhaps most intaglio printers want to be able to print up to a certain size, and if you've got a plate burner with a vacuum frame, there's no need to mess around with anything else--unless you need to be portable.

Keith--You wouldn't want any kind of liquid involved in such a process, because it would soften the two emulsions that are face to face and make a mess, or if you are using inkjet negs, it would likely make the ink run, which is another mess.

Don Bryant said:

Keith are you trying to pull my leg? Contact printing isn't rocket science, there is no need to make it complicated.

Don

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Oh I'm not deliberately pulling your leg, just idly musing about how to get the best possible contact. I was thinking about doing film-to-film contacting this way, that's what I had in my head. I mean, I did [RC] paper-to-paper contacts once with water in between and got sharp results... in the areas that didn't have bubbles :rolleyes:

Thanks for your comment, David.

I don't have an exact answer for you, I haven't done any "print plate" work at all. However, you can approximate a contact frame with 2 plain sheets of glass large enough that you can put a gallon bottle (drinking water or darkroom chemicals) on each corner. Easier to do if your UV source looks "up", or just use the sun for a quick test.

I finally (after many years of contact frames) built a cheap homemade vacuum system (peg board and a shop vac). It is noisy, but I must admit I'll never go back to split frames!

Tom

freedda said:

I'm wanting to make a portable UV exposure unit for my ImagOn plates. I was considering using a contact print frame to hold the plate and transparency together. This would be instead of a larger, heavier, and more costly vacuum frame.

Will this method work? I know contact print frames are used for solar plates and of course for photo contact printing, but there is always the issue of "light leak" with photo-polymer films if there is not good enought contact between the plate and transparency.

Best, David.

Click to expand...

David,

Frankly you can find NuArc vacuum easels for a song. Kick in a new oil-less vacum pump and you can be up and running for about $100. About the same price as a new high quality 8x10 contact printing frame.

Don Bryant