What to look for during exposure?

[gr82bart]

OK last question, I promise!

So I have this fancy contact printer with the 'split' hinged back. Supposedly, this is useful so that I can look at the PT print during exposure without losing registration.

What exactly am I suppose to look for?

I mean, I've read a couple books - well skimmed through them really - and read a couple different websites, but nowhere does it tell you what you're suppose to look for. Every reference was unanamous in stating to remember the exposure time for the UV source used. If that's the case what's the point of the hinged back?

Thanks again, Art.

 

[donbga]

OK last question, I promise!

So I have this fancy contact printer with the 'split' hinged back. Supposedly, this is useful so that I can look at the PT print during exposure without losing registration.

What exactly am I suppose to look for?

I mean, I've read a couple books - well skimmed through them really - and read a couple different websites, but nowhere does it tell you what you're suppose to look for. Every reference was unanamous in stating to remember the exposure time for the UV source used. If that's the case what's the point of the hinged back?

Thanks again, Art.

Art,

If you print palladium by inspection the thing to look for is when you have a "whisper" of an image. Once you have a very pale image with very slight detail in the highlights your print has probably been exposed enough.

Don Bryant

 

[Joe Lipka]

It is possible to judge exposure using the split back part of a printing frame, but I have never done so.

I have used the traditional photographic method of test strip to get to the basic exposure. I have made my decisions after developing, rinsing, clearing, washing and drying the test strip. Of course it takes longer, but I have a better idea what the finished print looks like. Once you understand your exposure, then you can work backwards to know just what a "whisper of an image" (really like that phrase, by the way) means to you.

 

[colrehogan]

If you are using a print out process (POP) such as the Ziatype, you can judge your print's exposure by opening up one side of the print frame. If using a develop out process (DOP) such as pt/pd, you can look for the faint image that Don mentioned above. That is what the hinged back is for, to allow you to inspect your image during the exposure process.

 

[Poptart]

It's actually quite noticable with all the processes I've printed. Gum becomes a bit darker than the coating and cyanotype lightens like faded jeans. I forget what Van Dyke does.