Liquid Emulsion on Canvas

[Photo Engineer]

Sometimes, emulsions in gelatin or polymer will not stick to a surface. It is then necessary to coat a first layer (sub) that is compatible with both the emulsion and the support. Gelatin alone is often used with a hardener and spreading agent.

PE

[stormbytes]

Borrowing from Rockland Colloid's Faq's:

"Liquid Light and Ag-Plus prints consist of colloidal silver grains in a gelatin binder"

Considering this, is there any point to "sub'ing" with a layer of gelatin (am I using the term correctly?) with canvas as the target medium or does the gelatin/emulsion suspension sort of 'auto-sub' ?

The RC Faq seems to talk about sub'ing only in terms of ceramics or glass, which is another reason I'm asking.

[Photo Engineer]

Well, the answer is "it depends".

I dont sub my glass plates and have no problem, but others sub them complaining of problems.

You have to try a few to find out what is best for your workflow.

PE

[stormbytes]

Thanks PE. More then a fair response.

Half a pound of gelatin is going to run me an extra $20 or so from Artcraft.

Can't blame a guy for trying to err on the side of cheapness :-)

I'm not sure if I should start another thread or simply ask here, so I'll be lazy:

Same question for Gum Bichromates on canvas, to sub or not to sub?

[Photo Engineer]

Again, that depends.

Coating on a textured support will be more difficult than a smooth support and there are other factors involved here.

IDK what gelatin Artcraft sells. I do know that the Formulary sells Kodak Photograde Gelatin.

PE

[CMB]

Most commercially available "artist" canvas comes with a "subbing" or primer layer that serves two functions: 1. It smooths out the canvas weave (multiple subbing layers provide smoother surfaces) and 2. It improves the receptivity to subsequent "topcoats" (such as your proposed Liquid Light) or most commonly, oil, acrylic and watercolor paints. This subcoat is rarely made of gelatin - usually PVA or a similar substance. So unless you have obtained raw, un-subbed canvas, there should be no necessity for you to gelatin coat the canvas to prepare it for your purposes. I would suggest that you obtain unmounted canvas in rolls (or sheets) and after processing, mount it in on stretcher bars.

In the early 90's, UltraStable coated several hundreds of thousands of square feet of canvas for IRIS printers and was considered to be the "gold standard" for fine art giclee printers. The emulsion was virtually identical to the gelatin emulsion used to coat
final transfer papers for the UltraStable Pigment process.

[stormbytes]

Thanks PE. More then a fair response.

Half a pound of gelatin is going to run me an extra $20 or so from Artcraft.

Can't blame a guy for trying to err on the side of cheapness :-)

I'm not sure if I should start another thread or simply ask here, so I'll be lazy:

Same question for Gum Bichromates on canvas, to sub or not to sub?