Lippmann Plates - silver "mirroring"?

Silverhalide Emulsions / Chemistry.
ThePhotoChemist
Posts: 3
Joined: Thu Sep 24, 2015 12:50 pm

Lippmann Plates - silver "mirroring"?

Post by ThePhotoChemist »

Hi everyone,

I've been playing around with Lippmann plates here and there. Most recently I made a batch using Darran Green's recipe in "The True Color Photography". I followed the recipe to a tee, except I used ethyl violet as a red sensitizer instead of pinacyanol.

Plates were developed in GP-2 (15 + 100) for 3 minutes. Upon inspection, all the plates seemed to have developed a mirror-like finish on the outside of the emulsion! A blue sky can barely be seen in one plate, but the mirroring more or less fogged out the colors. Transmitted light still shows a red negative, just as described.

Does anyone have any ideas as to what happened? I have no experience with AgX holograms, so this is all new to me. The mirroring didn't seem to vary with exposure, and I ran out of plates before I could experiment with dilution.
Martin
Posts: 131
Joined: Sat Apr 04, 2015 2:36 am

Re: Lippmann Plates - silver "mirroring"?

Post by Martin »

ThePhotoChemist wrote:Does anyone have any ideas as to what happened? I have no experience with AgX holograms, so this is all new to me. The mirroring didn't seem to vary with exposure, and I ran out of plates before I could experiment with dilution.
Maybe something like this happened(???):
https://archivesandspecialcollections.w ... mirroring/

http://notesonphotographs.eastmanhouse. ... -mirroring

In the context of holography I've seen this kind of behavior with some PFG-03 batches.
ThePhotoChemist
Posts: 3
Joined: Thu Sep 24, 2015 12:50 pm

Re: Lippmann Plates - silver "mirroring"?

Post by ThePhotoChemist »

Martin wrote:
ThePhotoChemist wrote:Does anyone have any ideas as to what happened? I have no experience with AgX holograms, so this is all new to me. The mirroring didn't seem to vary with exposure, and I ran out of plates before I could experiment with dilution.
Maybe something like this happened(???):
https://archivesandspecialcollections.w ... mirroring/

http://notesonphotographs.eastmanhouse. ... -mirroring

In the context of holography I've seen this kind of behavior with some PFG-03 batches.
This was my first thought! I have a few antique glass plates that have experienced this. My mirroring seems to be uniform all across the plate, however.

I emailed Darran Green, he offered that the ammonium thiocyanate content may be too high in the GP-2 stock. Has anyone had experience with the GP-2 kit from the Photographer's Formulary?

It's possible, though unlikely, that I fogged the plates while they were drying.

Here's a picture of one of the plates. The mirror is very much in the emulsion, and cannot be rubbed off.
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photo2.JPG
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ThePhotoChemist
Posts: 3
Joined: Thu Sep 24, 2015 12:50 pm

Re: Lippmann Plates - silver "mirroring"?

Post by ThePhotoChemist »

Just made another batch of plates -- exact same setup, no more mirroring! I even got some colors this time around!

I had a leftover plate from last batch that I forgot to clean, which still "mirrored" in the GP-2. But subsequent plates showed no sign of it. I'm guessing I (or a room mate... ) may have fogged these plates somewhere along the line.
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