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menglert
04-29-2007, 05:07 PM
Hello,

This is somewhat similar to the question I posted in the alt forum. Although, I would like to know how to make the gelatin coatings for paper. Could someone please shortly describe the process and ingredients?

I only want to coat with a gelatin layer, then after that is coated, paint my emulsion on top of it (Kallitypes). Does this seem feasible?

-Martin

Ryuji
04-29-2007, 05:14 PM
What you are referring is usually called "sizing" and it is described here:

http://wiki.silvergrain.org/wiki/index.php?title=Gelatin_sized_paper

Let me know if there's any question or need for clarification.

Basically, you typically coat paper with 2 to 3% of plain gelatin solution and let it dry. Most people use a bit of hardener (lined from the article above) in the gelatin to prevent potential troubles. These things were discussed to death on alt-photo mailing list (probably the best place to ask technical questions) so you might want to search archives there.

Ryuji

menglert
04-29-2007, 05:20 PM
Is it ok to use regular gelatin from the market?

Thanks,
Martin

Photo Engineer
04-29-2007, 05:23 PM
Do not use regular gelatin from the market. Get a 250 bloom photo grade gelatin from a reputable photgraphic supply house.

PE

menglert
04-30-2007, 12:43 AM
Thanks for the info everyone.

Is there a way I can make the surface smoother after sizing? Maybe putting it in a drymount press with a ferrotype plate?

-Martin

Ryuji
04-30-2007, 01:07 AM
Using hot pressed paper stock is the easiest.

Next step up is to use a polymer blend described on the page I put before. It's also useful to give two coats of sizing, but this will pretty much require hardening of the gelatin size, at least for the first coat.

If you want anything smoother than this, the only obvious method is to use baryta sized paper.

I'm not sure if baryta sized paper works well with kallitype. If plain gelatin size works well, I don't see why baryta wouldn't work, but if you want to be sure, you can look up the alt-photo archive, ask a q there, or otherwise ask other kallitypists.

menglert
04-30-2007, 01:14 AM
Using hot pressed paper stock is the easiest.

Next step up is to use a polymer blend described on the page I put before. It's also useful to give two coats of sizing, but this will pretty much require hardening of the gelatin size, at least for the first coat.

If you want anything smoother than this, the only obvious method is to use baryta sized paper.

I'm not sure if baryta sized paper works well with kallitype. If plain gelatin size works well, I don't see why baryta wouldn't work, but if you want to be sure, you can look up the alt-photo archive, ask a q there, or otherwise ask other kallitypists.

Thanks for the info... I think I'll try this.

-Martin