Liquid Emulsion on Canvas

[thefizz]

I will be trying out liquid emulsion on an artist's canvas which comes stretched over a basic wooden frame.

I have read that the emulsion will expand when wet and shrink when dried, so my question is should I remove the canvas from the frame before developing. This would allow it to expand and shrink easier. I had been thinking of leaving the canvas on the frame and putting it upside down in the developing tray.

Anyone see any problems with that?

Thanks,
Peter

 

[tormod]

Do any one know someting about this?

tormod

 

[magic823]

Works fine not on the frame. Its what I did for the print exchange last time. Size the canvas first and then the liquid emulsion. Expect about a 50% failure rate though (at least that's what I average.)

Steve

 

[thebanana]

I've never had much luck with artist canvas. The problem is that it is very porous, so the emulsion seeps into the canvas. In order for a neg to properly develop it needs a smoother surface.There may be some way to prep the canvas, but you would need to find a substance that would withstand the developing and washing process. Artist paper on the other hand, seems to be easier to get results from. The best luck I ever had was using ceramic tiles or glass. It both cases, the surface needs to be roughed up considerably using sandpaper before applying the liquid light.

 

[Photo Engineer]

One of the problem is that Liquid Light and other emulsion products don't contain a hardener. Therefore, it can wash off during processing.

Another is that it probably does not contain enough or any surfactant. A surfactant will help spread it evenly on the surface of the canvas. And, it may take two coatings.

I can't say for sure, as I make my own emulsions, but I have been able to coat my emulsions on canvas with little problem, but see difficulties if I leave out or vary hardener or surfactant.

I would suggest adding either chrome alum (10%) or glyoxal (10%) to the emulsion, about 5 ml / 150 ml of emulsion. Coat and let dry for about 4 hours or more and then process.

Another alternative is to soak in a pre-hardener and omit the hardner.

PE

 

[smieglitz]

I've never had much luck with artist canvas. The problem is that it is very porous, so the emulsion seeps into the canvas. In order for a neg to properly develop it needs a smoother surface.There may be some way to prep the canvas...

I've used canvas gwoo sizing (i.e., wabbit skin gwoo) successfully fow duewing gum bichwomate pwints on paypuhs. I suspect it would cweate a pwopaw substwate fow pwinting wiquid emowshuns on canvas. Next choice would be to twy sizing with someting wike 250 bwoom ossein (hawd gewatin) or maybe give it a bwushing of ahwbwumen (egg white) twying to not genewate too many bubbles in the pwocess.

Wegawds,

smiegwitz

 

[glennfromwy]

Rockand Colloid makes a Liquid Light emulsion specifically for fabrics. You may want to check that out. Otherwise, I would say leave the canvas on the stretcher frame and apply several coats of emulsion. Use a hardening fixer. Be really careful not to exceed 68° F, also. Gentle agitation and wash. Use hypo clear to reduce wash times. Good luck. I'll bet it would be beautiful.

 

[nworth]

I have no experience in this area, so this is a pure guess. Sizing the canvas with gelatin (several coats of dilute gelatin solution) might be a way to mitigate the coating problems.

 

[Willie Jan]

I left the canvas on the wood when working with it. Some canvas i used was ok and others soaked the emulsion up. So a gelatin prefix would be good to do.

The nice thing about leaving the wood around the canvas is that you can develop/fix the picture with floating. When the wood gets wet be sure to wash good because the develop/fix can get deep into the wood.

 

[stormbytes]

What exactly does "subbing" with gelatin mean? Could someone describe a workflow?

 

[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?

 

[poncho villa]

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?

 

[poncho villa]

Hi this is poncho villa from el Paso , Juarez Mexico. After you stretch your canvas onto the frame you paint the raw canvas with.a white alkloid enamal paint. When that drys it will take a base very well which you spread your emulsion on. Compliments of poncho villa photographic emulsion technologist, black and white negative and positive emulsions for mural size landscapes on canvas

 

[poncho villa]

Hopefully your familiar with bases you can compound that can stick and will accept an emulsion ,development is by floating with 6 mil plastic attached to rear of frame to keep developer off rear of canvas