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[[File:HCRGimage010.gif|right]]
aka The Home & Studio of E. Wesly + Sons
Names withheld to protect the guilty!
It never failed to amaze me that those slick black boxes
were made by Empak, in a suburb of Minneapolis, Minnesota, USA, shipped across
the ocean, filled with the Lippmann emulsions in Belgium and back here
again. I wonder how much that
added to the price of the plates.
Built-In Pre-Swell, so that the replay color was
automatically shifted about 25-35 nanometers even when using a
develop-rehalogenating bleach scheme, which should retain the recording fringe
pattern spacing. To retain laser
color fidelity this bloating agent had to be washed out <u>before</u>
exposure. Nobody should be forced
to handle things in the dark more than is necessary, especially since the
emulsion could be damaged or fogged before shooting the hologram. Let's hope nobody else is brilliant
enough to come up with that marketing scheme again! The problems it created! Why put something in that nobody really needed?
Let's have a contest to see who has the wildest things to
do while wiling away the settling and developing times. What is on <u>your</u> mind?
I got mine from my undertaker buddies.
[1] See for example, Zone System Manual, Ansel Adams, the negative, etc.
[2] Private conversation, circa 1983.
[3] Tell the tales of woe of the instruction sheets,
including how worthless the Agfa ones were. Holographic paper collectors.
[4] I still have it in my permanent collection! The earliest publication that I have of
the formula in my collection is Ostrovski,...
[5] My own paper, Recycling of Holographic Plates... Sorry for the sketch footnotes! Maybe when this gets published for real!
no edit summary
|-
| Part A || ||
|-
| || 15 g || Pyrogallol
|-
| || 5 g || Metol
|-
| || 1 L || Water
|-
| Part B || ||
|-
| || 30 g || Sodium Carbonate
|-
| || 7 g || Sodium Hydroxide
|-
| || 1 L || Water
|}
=== The Pre-hardener Problem ===
The idea of pre-hardening the plates doesn't seemlike such a good idea to me. Theonly photographic process that comes to mind that requires such a step was theoldold Ektachrome E-4 color process. The untreated film was not capable of withstanding the high temperaturesnecessary for short process times, so this pre-developer step was added.
But what really makes me queasy are two of theconstituents of the solution; Formaldehyde and potassium bromide. Formalin solution is not easy to comeby; even just having the stuff in a darkroom doesn't sit right with me. It belongsin an embalming room<ref>I got mine from my undertaker buddies.</ref> Perhaps in Eastern Europe this stuff isn't considered that dangerous,but here you will be paying a bundle in Hazardous Material Shipping Charges!
The other component in this bath that raises one ofmy eyebrows is the potassium bromide. I know from experience that solutions of bromide can <u>erase</u> alatent image!<ref>My own paper, Recycling of Holographic Plates... Sorry for the sketch footnotes! Maybe when this gets published for real!</ref> Although it is a minute amount, anything that slows these plates downshould be avoided.
But just for the sake of you, dear readers, I gotahold a hold of some Formalin solution and made up a batch of this toxic waste. It appears to be necessary for the -03 emulsions.
[[File:HCRGimage008.gif|right|The Ultra-Fine Grained Crew. It seems like a tie between the BB 640 developed with Pyro and bleached in PBQ and the PFG-03M and its GP2 colloidal developer.]]
== Conclusions ==
[[File:HCRGimage010.gif|right]]
Figure Five shows the full-plate holograms using
the best exposure and developer combination based on the above trial and error
a better idea of the signal to noise of the emulsion. They were photographed against a Kodak 18% Gray Card to give
some idea of relative diffraction efficiency.
=== Pricing ===
So I hope that this Holographic Consumer Report
will help others spend their hard-earned dough wisely!
== Notes and References ==
<references />
