liquid light and a brain

[ErinHilburn]

So last night I tried using liquid light on a clay brain that I had created for one of my collabrative pieces. I followed all the instructions covered the brain with an oil-based polyurethane coating twice. I put the emulsion on twice as well then I made pieces of paper with the emulsion and held them at the same level the brain would be to get exposure time. Well after I got the accurate times and wrote them down I started exposing the different areas of the brain being sure to use light proof things to block the other areas of the brain. When I developed it the brain turned all black. So I scrubbed off the emulsion and tried again and ten seconds less than the previously used time. There was no diffrence in the exposure at all. So I tried once more and exposed for only five seconds which was half of the last exposure time I used. This time I had a visible image but only lightly. I have several other projects that I am using liquid light on in the future. Can anyone tell me why I had such a problem and how I can avoid it in the future. And why would a five second exposure be too light, but a ten second exposure be completely and totally black? Is liquid light just super sensitive. Any help or suggestions would be greatly appreciated. This is the first time I've used a liquid emulsion. Is there any way that the fact that the brain wasn't a smooth surface be part of the problem?

Thanks,
Erin

 

[Photo Engineer]

Erin;

It might be ingredients (chemicals) in the clay or the polyurethane that are fogging the LL, although your problem does not sound like that. If chemical fog was taking place, it would be constant regardless of exposure.

OTOH, you may be washing something out of the clay as you repeatedly recoat it with LL and this might be decreasing the chemical fog. IDK.

It certainly is odd. But, the fact that it was not a smooth surface is not part of the problem.

I'll give it more thought.

PE

 

[ErinHilburn]

I had considered the clay being a problem. That is why I coated it with a sealant beforehand so that it wouldn't absorb anything and none of the clay would be lost in the chemicals/wash. I even coated it twice. I honestly have no idea what I did wrong. But it must have been me since the liquid light worked on the paper test strips I made.

 

[Donald Qualls]

How long did you let the urethane "varnish" cure before coating with emulsion? From what I recall, many urethane coatings require curing times of up to a week before they quit outgassing, and the catalysts they contain to promote curing might well fog silver halides. If you can do so, try removing all the gelatin (chlorine laundry bleach does an admirable job of that) and simply let the brain stand in a warm, dry location for a week, then try coating and exposing again...

 

[ErinHilburn]

ok I let it dry for a couple of days, so its possible thats the problem. Thanks a lot for your help.
-Erin