Contact print frame material for ultra thin papers?

Hi there,

Are you contact printing thin papers? How do you stop light passing through the paper and bouncing back off the contact printing frame during exposures?

I'm printing with 21gsm Japanese Gampi and have been using a piece of thin, very black, somewhat firm open cell foam.

Have you discovered some other material that's working for you?

Hello, MurrayMinchin @
Are you coating 21gsm Japanese Gampi and contact printing ?????

When I contact print film, I put matt black paper behind it. You can paint the contact frame flat black.

MurrayMinchin said:

Hi there,

Are you contact printing thin papers? How do you stop light passing through the paper and bouncing back off the contact printing frame during exposures?

I'm printing with 21gsm Japanese Gampi and have been using a piece of thin, very black, somewhat firm open cell foam.

Have you discovered some other material that's working for you?

Click to expand...

I haven't used quite that thin papers. But I've also used an open cell black foam. Sometimes with a clear PE sheet between paper and foam, to trap moisture during exposure.

One problem has been fogging through the slit in the split back especially when exposing with sunlight. A strip of aluminium foil on the back takes care of that.

And with processes sensitive to humidity, like Argyrotype the PE sheet has to be in place to stop the paper from drying unevenly.

If you are having problems with reflections maybe one of those super black paints could be used?

joho said:

Hello, MurrayMinchin @
Are you coating 21gsm Japanese Gampi and contact printing ?????

Click to expand...

Yes.

Don_ih said:

When I contact print film, I put matt black paper behind it. You can paint the contact frame flat black.

Click to expand...

Thanks. Once I have 3 or 4 options, I'll test them against each other to see if there is any 'dark fog' around fine back lines.

FotoD said:

I haven't used quite that thin papers. But I've also used an open cell black foam. Sometimes with a clear PE sheet between paper and foam, to trap moisture during exposure.

One problem has been fogging through the slit in the split back especially when exposing with sunlight. A strip of aluminium foil on the back takes care of that.

And with processes sensitive to humidity, like Argyrotype the PE sheet has to be in place to stop the paper from drying unevenly.

If you are having problems with reflections maybe one of those super black paints could be used?

BLACK 2.0 – The world’s mattest, flattest, black art material | Stuart Semple: Official Homepage

Click to expand...

Thanks for the paint link...the one I found recommended building up multiple thin layers using an air spray gun. Yours looks much easier.

Do you live in a dry environment where you found that sandwiching your Argyrotypes in PE helps in holding the moisture level where you want them?

Also, are you steaming or using a humidity chamber? I live in a temperate rainforest and have a basement dimroom, so the relative humidity doesn't move much. Have dabbled with steaming only once...maybe I should try it again.

There might be another option.

Zone VI enlarging easels were painted yellow, much like the colour of Thomas Duplex sodium vapour safelights they sold for graded papers. Yellow is supposed to absorb the most UV light, so maybe a matte yellow paint would work as well...

MurrayMinchin said:

Do you live in a dry environment where you found that sandwiching your Argyrotypes in PE helps in holding the moisture level where you want them?

Also, are you steaming or using a humidity chamber? I live in a temperate rainforest and have a basement dimroom, so the relative humidity doesn't move much. Have dabbled with steaming only once...maybe I should try it again.

Click to expand...

I'm in northern Europe, so I wouldn't say it's very dry here. But during winter the RH can drop to 30% if it's cold outside. Then humidifying and using a PE sheet really helps.

I have a simple humidity chamber with a saturated solution of salt (NaCl). And sometimes steam over a sink with hot tap water.

Another trick is to sandwich a thick humid paper behind the print in the printing frame. Especially helpful if you are printing on thin papers that can't hold much moisture themselves.

FotoD said:

I'm in northern Europe, so I wouldn't say it's very dry here. But during winter the RH can drop to 30% if it's cold outside. Then humidifying and using a PE sheet really helps.

I have a simple humidity chamber with a saturated solution of salt (NaCl). And sometimes steam over a sink with hot tap water.

Another trick is to sandwich a thick humid paper behind the print in the printing frame. Especially helpful if you are printing on thin papers that can't hold much moisture themselves.

Click to expand...

Thanks for the tips.

At first I had all kinds of problems trying to coat this thin paper. Fell upon some steps which are working, at least for the time being:

1) Pre-wet the paper (torn to size with a thin border) on a sheet of glass with distilled water, making sure to brush it out flat (moving from the centre out works best, after 'draping' it gently into place) with a light touch and a hake brush until it has an even sheen.

2) Pat it dry (about half way) with paper towel.

3) Measure out sensitizer and brush it evenly onto the whole sheet of paper, right to the edges.

4) Place under a fan in the dark for about a half hour (typically a cup of coffee, tea, Photrio rummaging session, or doing the dishes) until it's dry. It stays stuck to the sheet of glass but peels up easily.

The extra water in the pre-wet step doesn't dilute the sensitizer because it evaporates off...its only purpose is to flatten and prepare the paper for the sensitizing step.

Thanks, I really need to try some japanese papers. They seem like nice challenge.

MurrayMinchin said:

Yellow is supposed to absorb the most UV light, so maybe a matte yellow paint would work as well...

Click to expand...

It really depends. Some black paints are as effective UV absorbers as yellow paints. It really depends on the specific paint/pigment used and also factors like surface. Overall, you can't really go wrong with a black paint.