luminos liquid emultion problems

[dave_pemberton]

I just started working with luminos' variable contrast liquid

emulsion. I have done on two canvas boards and on both of them the

emulsion has pulled off in places. on the second one I did no

agitations, and it turned out much better, but still some of the

emulsion pulled off. I am about to my final print of this on a nice

stretched canvas. My question is this, I was under the impression

canvas did not need to be pretreated, do I need to coat with

polyurethane? is the canvas treated with something bad? and is it

something else I was doing not realated to the coat or the emulsion?

(i processed through ilford developer stop and fixer, and then let

soak in a tub of water)

[colmmccarthy]

How long do you allow the emulsion to dry before printing?

[dave_pemberton]

I coated two canvas boards and a streteched canvas at about 1:45 (11-12) one day, and worked the two canvas boards next day(11-13) at about 2. the canvas is still sitting in the dark, it I'm gonna go ahead and do it tomorrow (11-15) so hopefully everyone will respond by then.

thanks

-dave

[cane_prevost]

I think you need to apply a subbing material to the canvass before the emulsion. An oil based poly works. Everything I've seen says that canvass needs to be pretreated. Use oil based not water based poly. The water based can come off in processing.

[snapamhall]

I know you posted this a while ago, but for future refrence- canvas generally has a residual chemical content from the manufacturing process, and requires either extensive washing prior to coating, or the use of a oil-based primer (alkyd primer) to maximize tonal range and sharpness. Eliminating agitations might not be the best idea either, as you could fail to remove all chemicals, causing spots to show up later. cheers.