Search found 795 matches
- Sun Apr 28, 2024 4:42 pm
- Forum: General Holography
- Topic: noise due to a large (extended) object
- Replies: 0
- Views: 32
noise due to a large (extended) object
Since the forum has been slow lately, I would like to pose the following question (which I've been wondering about). Say we make two holograms that measure 10cm X 10cm. These would be single-beam Denisyuk DCG reflection holograms (with a wide dynamic range associated with DCG, if that makes a differ...
- Sat Mar 30, 2024 6:00 am
- Forum: Beginning Holography
- Topic: Hello! Good books for interested peeps?
- Replies: 1
- Views: 646
Re: Hello! Good books for interested peeps?
Welcome to the forum. Practical Holography by Saxby, G., I saw someone mention 4th edition is best, but is it really worth an extra $140 over a 3rd edition In my opinion, probably not. My favorite is the 2nd edition. As for getting started in holography, I would recommend a green (532nm) laser of at...
- Tue Mar 19, 2024 1:30 pm
- Forum: General Holography
- Topic: beam ratios: silver vs. polymer vs. DCG
- Replies: 5
- Views: 1148
Re: beam ratios: silver vs. polymer vs. DCG
Wow, thank you Din and Joy! Joy's comments seem to confirm my impressions about Bayfol HX200 photopolymer. When I did the first two, they were just simple Denisyuk with no extra object light. I didn't measure the reference/object ratio, but the reference must have been much, much stronger. White obj...
- Mon Mar 18, 2024 10:25 am
- Forum: General Holography
- Topic: beam ratios: silver vs. polymer vs. DCG
- Replies: 5
- Views: 1148
Re: beam ratios: silver vs. polymer vs. DCG
The Bayfol material is impressive, and it works reasonably well with a very high reference to object ratio. But, compared to (non-dye) DCG, it doesn't seem capable of very high brightness, without a certain quantity of object light. In my limited experience, that is. I did a hologram yesterday with ...
- Mon Mar 18, 2024 9:37 am
- Forum: General Holography
- Topic: beam ratios: silver vs. polymer vs. DCG
- Replies: 5
- Views: 1148
beam ratios: silver vs. polymer vs. DCG
Having done my first few photopolymer holograms (Bayfol HX200), it seems that polymer is more dependent on beam ratio equality (ideally ~1:1 for a reflection hologram) compared to DCG. It reminds me of silver halide, but perhaps not as extreme. Maybe this is due to the dyes present in polymer and si...
- Fri Feb 16, 2024 12:43 pm
- Forum: For Sale / Want to Buy / Trade
- Topic: Looking for photopolymer films
- Replies: 11
- Views: 20879
Re: Looking for photopolymer films
Like Bob said previously, the films have a stickiness comparable to a post-it note. First remove the PE protective film by sticking a piece of adhesive tape to the corner, and peel it away. Then laminate it to your glass (a rubber roller is good for this). Bubbles and dust can be a problem at this s...
- Tue Jan 30, 2024 12:15 pm
- Forum: For Sale / Want to Buy / Trade
- Topic: Looking for photopolymer films
- Replies: 11
- Views: 20879
Re: Looking for photopolymer films
Regarding availability, I ordered from Geola in Lithuania recently with no problems. They are professional and fast.
https://www.geola.com/product/photopolymer/
The total cost including shipping to the US was 149 Euros for 36 sheets of HX200 (2 packs of 18 each) of the 10cm X 10cm size.
https://www.geola.com/product/photopolymer/
The total cost including shipping to the US was 149 Euros for 36 sheets of HX200 (2 packs of 18 each) of the 10cm X 10cm size.
- Thu Jan 25, 2024 9:44 am
- Forum: For Sale / Want to Buy / Trade
- Topic: Manual for the Coherent Sapphire 532-300
- Replies: 7
- Views: 2255
Re: Manual for the Coherent Sapphire 532-300
What I tried to convey with "reasonably" collimated (a poor choice of words, I admit) was that it's not wildly diverging coming out of the aperture (and that it could be "tamed" with lenses).
- Thu Jan 25, 2024 6:56 am
- Forum: For Sale / Want to Buy / Trade
- Topic: Manual for the Coherent Sapphire 532-300
- Replies: 7
- Views: 2255
Re: Manual for the Coherent Sapphire 532-300
Hi Andrei, Thanks for the tip about the Michelson! Sounds like a very good idea. That's fascinating that a ring cavity (Coherent 532) has mode hops. I think that for many types of lasers, this is something that can be accepted and dealt with. I could be mistaken, but I thought FPT FT means fiber-cou...
- Wed Jan 24, 2024 2:03 pm
- Forum: For Sale / Want to Buy / Trade
- Topic: Manual for the Coherent Sapphire 532-300
- Replies: 7
- Views: 2255
Re: Manual for the Coherent Sapphire 532-300
I can't help with the manual, but I recently bought a similar Sapphire 532-300 (formerly fiber-coupled) from Dave on Facebook. Dave said it worked for holograms, and that was good enough for me. I haven't tried it yet. By the way, my Sapphire 488-200 does appear to mode-hop once in a while (at certa...