my first attempt hologram

Simple answers are here! For Theory look in General Holography.
Locked
blue_electric_71

my first attempt hologram

Post by blue_electric_71 »

Here is my first hologram using the integraf JD-4 kit ..this one turned out the brightest out of 12 exposures...It's still quite dim but spraying black paint on the emulsion side helped somewhat.


http://vimeo.com/12393626


However, every attempt after that turned out way too dim..i'm not sure what the cause for it is. I tried to half my exposure from 10 to 5 seconds and also increased developing time from 10 seconds to 45 seconds...The results are quite sharp so i guess it's not a isolation problem

Also i'm not quite sure when to change chemicals for best results. I have changed the developer twice (using dozen plates in 2 days) and bleach once, rinsing water twice and still use the same photo flow solution i mixed on Sunday.

And also i have a problem identifying the emulsion side of the plate after packaging which resulted in a couple of flipped exposures. Since my hands are quite dry I use a cup of water to moist my finger to be able to feel the sticky side of the plate..but sometimes it's just too hard to tell. Is there a better way for this?

Some advice would be greatly appreciated :angel:
rzeheb

my first attempt hologram

Post by rzeheb »

Actually, I thought that hologram you posted looked quite nice!

Anyway, you may want to conduct a few test exposures to zero-in on the optimal exposure time which I suspect may be too short. You can block the light from succeeding strips of a plate and test, say, 5 sec, 10 sec, 15 sec, and 20 seconds on a single plate then select the time that gives you the brightest image. Once you have better optimized the exposure time you can burn a few plates to dial-in development time, which for reflection should be pretty dark (you may want to try 1 to 2 minutes).

Sounds like your solutions should be fine. I use developer for only 1 session then make it fresh for the next one.

Ron
Jem

my first attempt hologram

Post by Jem »

I'd say for one of your first holograms that looks pretty good :)

As regards finding which side of the plate the emulsion is on... I gently breath on the plate, the side that mists up is the non-emulsion side. Why not try it, breath on both sides of the plate in turn and note the difference.

Cheers

Jem
bernardb

my first attempt hologram

Post by bernardb »

Looks really nice!

Good job :angel:
BobH

my first attempt hologram

Post by BobH »

Good show!!! The holograms with the emulsion toward the viewer can be covered with another glass plate (bad exposure with emulsion bleached off). Either UV curing adhesive or epoxy can be used.
blue_electric_71

my first attempt hologram

Post by blue_electric_71 »

Thanks for the input guys!
You can block the light from succeeding strips of a plate and test, say, 5 sec, 10 sec, 15 sec, and 20 seconds on a single plate then select the time that gives you the brightest image. Once you have better optimized the exposure time you can burn a few plates to dial-in development time, which for reflection should be pretty dark (you may want to try 1 to 2 minutes).
Ron, that's a really clever way to test exposures you described..i will try that, and at the same time saving some precious plates in the process. I just made another exposure just now, at 20 seconds (since I previously tested 5 and 10 seconds) with 1 minute of developing. It's still drying on the shelf as we (I) speak.
As regards finding which side of the plate the emulsion is on... I gently breath on the plate, the side that mists up is the non-emulsion side
I applied Jem's 'breathing on the plate suggestion' an on my latest session...works like a charm Thanks! Brilliant . I felt more relaxed during exposure too, knowing the plate had the right orientation.
At first I was reluctant reflecting the safe light on the plate..But I took a chance withe the green bulb i bought at the photo store.
The holograms with the emulsion toward the viewer can be covered with another glass plate (bad exposure with emulsion bleached off). Either UV curing adhesive or epoxy can be used
Yes, that would probably be the best solution if you want to save a perfectly good hologram that's exposed that way. But only when necessary. And i guess these techniques could be useful as protection for transmission holograms.

Thank you again for the helpful tips. I'm down to the basement now :D

Gilbert
Tom B.

my first attempt hologram

Post by Tom B. »

For all glass plates I have tried, the emulsion side is on the "clean edge" side of the plate - I think when they separate the plates (made in large sheets) , they scribe the glass on the non-emulsion side with a carbide tool leaving a slightly ragged line, then break along the lines leaving a perfect edge on the emulsion side. The difference is visible by close-up inspection under safelight, and is also detectable in the dark by running a thumbnail along the edge. The emulsion edge feels smooth, while the other edge is noticeably rougher. You can check to see if you can feel the difference with an exposed plate.
rzeheb

my first attempt hologram

Post by rzeheb »

Tom B. wrote:For all glass plates I have tried, the emulsion side is on the "clean edge" side of the plate - I think when they separate the plates (made in large sheets) , they scribe the glass on the non-emulsion side with a carbide tool leaving a slightly ragged line, then break along the lines leaving a perfect edge on the emulsion side. The difference is visible by close-up inspection under safelight, and is also detectable in the dark by running a thumbnail along the edge. The emulsion edge feels smooth, while the other edge is noticeably rougher. You can check to see if you can feel the difference with an exposed plate.
Tom, what a great observation. I tried your "thumbing the edge for roughness" technique, and it works great! Certainly beats what I used to do, which was to put a corner of the plate between my lips and feel for the sticky side. Ron.
BobH

my first attempt hologram

Post by BobH »

That's one excellent tip Tom!!! :clap: :clap: :clap:

I've always breathed on it and looked for condensation on the glass side, but sometimes one doesn't want the potential for spit on the emulsion when testing for orientation. :doh:
Locked