Search found 58 matches

by vasimv
Fri Nov 08, 2019 7:45 pm
Forum: General Holography
Topic: Easy to build Peltier cooling for Osram PL530
Replies: 4
Views: 6436

Re: Easy to build Peltier cooling for Osram PL530

I have designed analog driver for PL530 include peltier driver, but currently I have no time to produce complete lasers... see for inspiration: viewtopic.php?f=11&t=9912&start=30 Yes, looks good but i was too lazy to make PCB. And i have good experience in using MCUs for that kind of regula...
by vasimv
Thu Nov 07, 2019 9:29 pm
Forum: General Holography
Topic: Easy to build Peltier cooling for Osram PL530
Replies: 4
Views: 6436

Easy to build Peltier cooling for Osram PL530

The Osram PL530 (DPSS laser module) is cheap and has very good beam quality but quite hard to run properly. After some unsuccessful attempts and one destroyed module i've found the laser is very sensitive to temperature and requires quite precise cooling. So, i've started to build cooling/powering s...
by vasimv
Fri Nov 01, 2019 8:27 am
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 10080

Re: Diazo gelatin (DIAG)

I tried a couple of dyes but didn't notice any sensitizing effect. Found the patent for spectrally sensitized diazo by adding "dithiocarbamates" with dye: https://patents.google.com/patent/US3778274 There are some dithiocarbamates with low toxicity available for purchase even on amazon (l...
by vasimv
Thu Oct 31, 2019 8:02 am
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 10080

Re: Diazo gelatin (DIAG)

That's amazing. What's your gelatin? The last time I tried this with my standard gelatin I was only able to record some dim transmission gratings. 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 - T...
by vasimv
Tue Oct 29, 2019 6:47 pm
Forum: DCG
Topic: Diazo gelatin (DIAG)
Replies: 7
Views: 10080

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. Do you think the DIAG stuff compatible with dye+TEA or TMG sensitizing? Seems it has high...
by vasimv
Tue Sep 03, 2019 3:55 pm
Forum: DCG
Topic: Ferric ammonium oxalate tests
Replies: 118
Views: 90979

Re: Ferric ammonium oxalate tests

I usually just add few drops of 10% soduium lauryl sulfate solution and it helps for gelatine and PVA emulsions enough to stay on the glass unless additional reprocessing with longer water exposure used. That's interesting. Usually surfactants are said to have a negative impact on layer adhesion (I...
by vasimv
Sun Sep 01, 2019 9:05 pm
Forum: DCG
Topic: Ferric ammonium oxalate tests
Replies: 118
Views: 90979

Re: Ferric ammonium oxalate tests

Around 1999 or so, Jeff Blyth published his silver halide diffusion method (which I think he updated and improved since then). I think in one of his papers (about that time or later), he detailed his glass preparation method. The diffusion method required that the gelatin adhere strongly to the gla...
by vasimv
Sun Sep 01, 2019 5:16 pm
Forum: DCG
Topic: Ferric ammonium oxalate tests
Replies: 118
Views: 90979

Re: Ferric ammonium oxalate tests

Wow, nice hologram. Quite a red-shift if you're exposing at 405nm. I think this really proves the viability of the ferric system, at least with your environmental conditions. Yeah, it works better in my temperature than non-hardened FEG but no stable result still. I hope to get better with mold coa...
by vasimv
Sun Sep 01, 2019 10:05 am
Forum: DCG
Topic: Ferric ammonium oxalate tests
Replies: 118
Views: 90979

Re: Ferric ammonium oxalate tests

I've diluted pre-hardened emulsion by adding 50% water (so, now it is 12g gelatine, 0.3..5g potassium alum and 1g FAC per 150ml of emulsion), easier to do coating. Looks like the emulsion requires more thickness. Did test with 200um and 80um mayer bars, first one has some red-shift to be visible but...
by vasimv
Mon Aug 26, 2019 10:01 am
Forum: DCG
Topic: Ferric ammonium oxalate tests
Replies: 118
Views: 90979

Re: Ferric ammonium oxalate tests

Got some promising results with pre-hardened emulsion (12g gelatine, 0.3..0.5g potassium alum, 1..1.5g of FAC per 100ml of emulsion), holograms aren't great (mostly in deep-blue/near-UV area) but better than in my most attempts. With mayer bar (i've used 120um bar, perhaps too thick) i was able to m...