Search found 95 matches

by Martin
Wed Jan 20, 2021 3:53 am
Forum: General Holography
Topic: Mounting Photopolymer Film
Replies: 3
Views: 143

Re: Mounting Photopolymer Film

With our own material back then (DAROL photopolymer that is) one could easily "index match" the photopolymer side of the polyester film to a glass plate with water, glycerol, glycols etc. (if I'm not mislead it also worked with white spirit). One could even laminate it with a warm gelatin solution. ...
by Martin
Thu Jan 14, 2021 11:31 am
Forum: Beginning Holography
Topic: A little more of beginners luck
Replies: 3
Views: 295

Re: A little more of beginners luck

Litiholo used to sell a blue (450nm) laser module - see: www.litiholo.com/hologram-lasers.html). Its power is only 5 mW though. Of course that's pretty moderate. Nevertheless, I could make holograms on DCG, FEG, photopolymer and diazo materials. The laser module I have works nicely without any mode-...
by Martin
Mon Jul 27, 2020 1:07 am
Forum: General Holography
Topic: Geola question
Replies: 12
Views: 1214

Re: Geola question

You may switch on an auxiliary incoherent light source during recording. This lowers the threshold energy required to initiate polymerization for the holographic (laser) exposure. It involves a lot of testing and fine tuning though.
by Martin
Tue Nov 19, 2019 9:50 am
Forum: Optics
Topic: Ruby LASER for holography
Replies: 6
Views: 1568

Re: Ruby LASER for holography

That's absolutely amazing! Congratulations!
by Martin
Sat Nov 02, 2019 4:39 am
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 4373

Re: Diazo gelatin (DIAG)

Martin wrote:
Sat Nov 02, 2019 4:21 am
I was thinking of improving mode stability/coherence length of a cheap 405nm diode...
See: https://www.coherent.com/assets/pdf/Sin ... torage.pdf
by Martin
Sat Nov 02, 2019 4:21 am
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 4373

Re: Diazo gelatin (DIAG)

Found the patent for spectrally sensitized diazo by adding "dithiocarbamates" with dye: https://patents.google.com/patent/US3778274 Interesting. The question though is if the diazo materials mentioned in this patent are available and compatible with gelatin. Interesting, but if i understand correct...
by Martin
Fri Nov 01, 2019 3:49 am
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 4373

Re: Diazo gelatin (DIAG)

Well, it is one of my alchemy attempts, i've mixed safranin O dye, TEA and TMG (2 times more than TEA) in same emulsion (from my previous experience - TEA provides good holograms but weak sensitivity and TMG increases contrast and sensitivity but weak holograms alone). This should work with Methyle...
by Martin
Thu Oct 31, 2019 3:05 am
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 4373

Re: Diazo gelatin (DIAG)

Interesting. I'm busy experimenting with dye+TEA/TMG (no dichromates) emulsions now and got good holograms with it last week but plan to return to experiments with FEG and speedball diazo stuff some time later. That's amazing. What's your gelatin? The last time I tried this with my standard gelatin...
by Martin
Tue Oct 22, 2019 3:54 am
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 4373

Diazo gelatin (DIAG)

Just noticed that I might have had it wrong about D.A.S. (diazidostilbene-2,2'-disulfonic acid salt), diazo gelatin ("DIAG") - see https://holographyforum.org/forum/viewtopic.php?f=7&t=620&start=30. Luckily, I had some ethanol D.A.S. solution left, which I had kept in my fridge for more than six yea...
by Martin
Mon Sep 16, 2019 6:17 am
Forum: General Holography
Topic: Silver halide sensitivityy enhancer
Replies: 10
Views: 4356

Re: Silver halide sensitivityy enhancer

I recently published a brief article on the hypersensitization of silver halide emulsions using a formate pre-soak., which I first mentioned in the Forum more than a decade ago. Took me all this time to try it out. See: https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10558/105580C...