Glass Plate Negs

[robert_fisher4]

I'm looking at making some dry glass plate negatives to use in a pinhole camera

I'm going to build. The albumen process is the one I'm finding the most

information on. The albumen is basically used as a substrate on the glass to

hold the silver when the glass is coated later with the silver solution. My

question is, would it be possible to use gelatin in place of the albumen?

 

Thanks in advance.

[jay_de_fehr]

Hi Robert.

 

Albumen is a UV sensitive emulsion, and would require VERY long exposures to daylight through a pinhole. You can make a blue sensitive emulsion to coat on glass plates, or you can use a ready-made emulsion, like Liquid Light. Ron Mowery is the resident expert on emulsion making and coating. You might post your question in the Alt process forum. Good luck.

 

 

Jay

[robert_fisher4]

Thanks Jay. I do know it's a slow emulsion to be sure. There isn't a lot of silver that adheres to the albumen substrate. Liquid Light is as slow or slower. About a 5 ISO if I recall. Maybe even as slow as 1. I don't know how archival it is either. Albumen glass plates are very archival. Didn't know there was an Alt Process forum here though. Didn't see it when I was trying to figure out where to post this question. I'll have another look.

[jay_de_fehr]

Hi Robert.

 

I think you might be confused about a few things. First, an albumen emulsion will have an EI something like .001 in sunlight, because it is only sensitive to UV, whereas a Liquid Light emulsion will give an EI somewhere between 3-12. Second, albumen emulsions contain an excess of silver nitrate, far more silver than camera films. Finally, albumen is not as archival as a gelatin emulsion, and will crack and yellow with age. I hope you find the information you're loking for. Good luck.

 

Jay

[robert_fisher4]

That information is different from what I've been seeing Jay. Anything I've been finding so far indicates that albumen emulsion is quite archival. I've not found anything so far that indicates an albumen glass plate is only sensitive to UV either. I'm still researching, obviously. Appreciate the help.

[terence_spross1]

While I'm not knowledgeable about the albumen process, I do know a major factor reguarding the aparent speed of these older processes: Early lenses sometimes did not pass UV light well and therefore exposure relied on the end of the curve in blue light sensitivity and the amount of UV that was passed. These often resulted in long exposure times. Obviously a pinhole does not attenuate UV, so the effective speed is faster if exposed in daylight that contains UV. (Modern lenses also pass UV better.)