Seeking tips from a more experienced holographer

[tschmelcher]

Hi there! I'm new to this forum. I'm a hobbyist holographer and I'm trying to figure out why so many of my holograms don't turn out. I'm hoping someone more experienced than me can take a look at my set-up and give me a few tips.

I use Slavich PFG-03M plates and process with JD-4 (I got all my materials from Integraf). My set-up is based on the basic set-up that Integraf describes in their handbook; I have a 5 mW laser embedded in a cup of sand, and separately I have a 9x9 baking pan filled with sand and on top of that I put both the subject and the plate (example photo is at the end). All of this is done on my bathroom counter, which is the only convenient, sturdy, and dark place in my apartment. I use a thick black book as the shutter. I always try to follow as many of the recommendations as possible, including storing the JD-4-A and the unexposed plates in my fridge.

My problem is that a lot of my holograms don't turn out and I don't know why. The most common problem I see is that all or part of the emulsion is "clouded" after developing and has no image on it. I've attached a picture showing a good example where the entire plate was covered in clouds. This was practically a brand new plate (manufactured in 2009/04, I think), so it should have been good.

Clouding on a developed plate

Clouding.JPG (145.74 KiB) Viewed 2910 times

I've read that "fogging" can be caused by unwanted exposure to light, but I've never seen a picture of fogging before so I don't know if this is the same thing or not ... Plus the clouding seems to just happen randomly, as far as I can tell. Another thing I see every now and then is that the image is just very faint.

Currently I'm trying to holograph a set of bright painted wooden figurines onto 4" x 5" plates. In the past I used to just lean the plate against my subject, but for this latest subject I've built a holder for the plates and subject out of some unused Ikea wooden shelf pieces that I've glued together with wood glue. There's are little cut-out rails in the sides that let me slide the plate in vertically.

Photo of my set-up

MySetup.JPG (143.36 KiB) Viewed 2910 times

So far this has produced one very faint image and the super-clouded one that I attached above, so I'm wondering if perhaps this is not a good set-up?

Some things that I'm worried about:

- Maybe wood just isn't rigid enough at small scales for doing holography?
- A lot of ambient laser light reflects off of the walls and mirror and gets around the shutter, so maybe the plates are already exposed by the time I go to lift the shutter?
- The distilled water that I recently bought says on the jugs that it is also ozonated. Maybe there are trace amounts of ozone in the water and it's chemically interfering with the developing process?
- Maybe my two D batteries are getting close to empty so the laser isn't stable anymore? (But I checked them with my multi-meter and they're still at full voltage ...)

Any tips would be greatly appreciated.

Thanks!

[JohnFP]

Wood is not a good material to use. Plus I would imagine the plate can move in those slots. Remember, the object/plate cannot move relative to one another by so much as even 1/4 wavelength (1/4 of .6 microns for a red laser).

Since you are not on a vibration isolation table, I strongly recommend leaning the plate directly on your object to insure they do not move relative to each other. Also, let the plate that is leaning against the object to set for a few minutes to stablize.

Also, you definitely want to block any stray light from hitting your plate. You may be able to put a box over your object/plate unil just a few seconds before your exposure. Then lift off the box and do you exposure.

[LarryD]

Hi there! I'm new to this forum. I'm a hobbyist holographer and I'm trying to figure out why so many of my holograms don't turn out. I'm hoping someone more experienced than me can take a look at my set-up and give me a few tips.

I use Slavich PFG-03M plates and process with JD-4 (I got all my materials from Integraf). My set-up is based on the basic set-up that Integraf describes in their handbook; I have a 5 mW laser embedded in a cup of sand, and separately I have a 9x9 baking pan filled with sand and on top of that I put both the subject and the plate (example photo is at the end). All of this is done on my bathroom counter, which is the only convenient, sturdy, and dark place in my apartment. I use a thick black book as the shutter. I always try to follow as many of the recommendations as possible, including storing the JD-4-A and the unexposed plates in my fridge.

My problem is that a lot of my holograms don't turn out and I don't know why. The most common problem I see is that all or part of the emulsion is "clouded" after developing and has no image on it. I've attached a picture showing a good example where the entire plate was covered in clouds. This was practically a brand new plate (manufactured in 2009/04, I think), so it should have been good.



I've read that "fogging" can be caused by unwanted exposure to light, but I've never seen a picture of fogging before so I don't know if this is the same thing or not ... Plus the clouding seems to just happen randomly, as far as I can tell. Another thing I see every now and then is that the image is just very faint.

Currently I'm trying to holograph a set of bright painted wooden figurines onto 4" x 5" plates. In the past I used to just lean the plate against my subject, but for this latest subject I've built a holder for the plates and subject out of some unused Ikea wooden shelf pieces that I've glued together with wood glue. There's are little cut-out rails in the sides that let me slide the plate in vertically.



So far this has produced one very faint image and the super-clouded one that I attached above, so I'm wondering if perhaps this is not a good set-up?

Some things that I'm worried about:

- Maybe wood just isn't rigid enough at small scales for doing holography?
- A lot of ambient laser light reflects off of the walls and mirror and gets around the shutter, so maybe the plates are already exposed by the time I go to lift the shutter?
- The distilled water that I recently bought says on the jugs that it is also ozonated. Maybe there are trace amounts of ozone in the water and it's chemically interfering with the developing process?
- Maybe my two D batteries are getting close to empty so the laser isn't stable anymore? (But I checked them with my multi-meter and they're still at full voltage ...)

Any tips would be greatly appreciated.

Thanks!

I don't know why Slavich or the vendors of these products don't try to clarify this (showing clear pics of the problem, and the correct way to avoid it,) especially since this combo (PFG-03M/JD-4) is what is offered to new comers as the starting point. I would bet that a very large percentage of people new to PFG03M see this, even pro holographers!

As an amateur, I have experienced very similar results trying to shoot PFG-03M and PFG-03C. In both cases the emulsion is said to be much a smaller grain size (than PFG-01) and softer emulsion. I am pretty sure you must pre-harden (with a hardening fixer?) your plates. Also note that you will typically see these go instantly black in the developer...almost totally black! Most docs that describe developing a silver halide hologram will say something like "...watch as the plate goes dark, in about 2 minutes. If you look through the plate at a safe light you should just barely see the bulb filament..." Not so with these plates, it's VERY black in less than a few seconds. I have got a couple (literally 2) decent holos (not cloudy) without hardening, but I have no idea why they worked and most others from the same batch of plates did not. BTW, when I was successful, the PFG-03M holos did seem "brighter" and "clearer" than those shot on PFG01, supposedly due to the smaller grain size.

I agree with JohnFP, go back to resting the objects against the plate, but also try a diffuse white object .vs the red painted ones. With the diffuse white objects you know that you are getting a better percentage of the light being reflected back to the plate. With the colored objects, the paints used could actually end up absorbing too much light at the wavelength of your laser, and your holo could be very dim.

If you continue to have problems, (but remain interested in holography after that :wall: ) I would suggest trying PFG-01 with the JD-2 developer. This appears to be a much harder emulsion (or maybe it's gets harder in the JD-2?) and I have never seen the cloudy scattering as in PFG03M. However, if you over-expose a bit it will have a tendency to shrink very slightly and shift your red holo to green. The holo below was shot with a red HeNE on PFG-01 and exhibits this shrinkage.

Catique holo from holographyforum contest. Shot on PFG-01 with Red HeNe.

catique.jpg (17.21 KiB) Viewed 2896 times

Good luck.

[tschmelcher]

Thanks you two! I guess I'll try leaning the plate against the figurines then. Not sure if they're heavy enough to hold it up though ... maybe I'll make a "sandwich" with something on the other side for it to all lean against. I did look at them under the laser light and the high-gloss red paint/lacquer seemed very bright. Also, just yesterday I started using two additional textbooks to block stray light from the laser, so that should help.

Larry, I know exactly what you mean about the plate going black after a few seconds. In total I've had about 5 decent shots out of 14, and most of the rest were clouded. Any idea how to pre-harden the plates? Right now I'm trying out the distilled water "pre-soak" step that some instructions recommend ... but maybe that's making the emulsion even softer and I should skip it?

[BobH]

I'd also recommend building a little housing for the laser to capture all light from it when the "shutter" is closed, but lets air flow freely around the laser to keep it cool. Might want to use a small fan to help with that. You could be fogging the plate when you handle it to load into the plateholder.

Also, there is no need for the cup and tray of sand in your set-up. No reason at all!

Finally, Hans Bjelkhagen recently mentioned somewhere that PFG-03C should NOT go black immediately in the developer as was mentioned by Larry and has been my experience too. He said that if it does, it means the material was fogged by being passed through x-ray scanners comming into the US, and is therefore damaged. I think that may be also true of the PFG-03M material you're using.

[LarryD]

Any idea how to pre-harden the plates?

I would try the recommended procedure from Slavich first. (But see Important Note below, too)

Formalin 37% 10ml
Potassium Bromide 2g
Sodium Carbonate 5g
Water to 1L


The above recipe came from : http://www.slavich.com/pfg03m.htm#hardener%C2%A0

Important Note: While looking at the above link I also noticed this comment "Ultra fine grain emulsions provide a bit more clear image than fine grain ones, but are very soft and are not recommended for hobbyists and beginners due to quite difficult processing and shorter life time." Emphasis on "...are not recommended for hobbyists and beginners..."

[tschmelcher]

That X-Ray explanation sounds very plausible. Come to think of it, this latest batch of plates seems to go blacker much quicker than the first batch I ordered. I seem to recall that the first batch took more like a minute. I'd assumed that the new ones were just more "potent" somehow ... but maybe it means they're bad, like you say, Bob. I might try going back and using up the previous batch that I ordered but didn't finish. Those plates are really old now (about 1 year), but I was at least able to produce images with them when I tried last week (though faint).

As for that hardener recipe, I see on the site that it is for use with GP-2. Supposedly JD-4 hardens the emulsion _during_ developing so that it isn't as soft as when using GP-2 (according to Integraf), so I'd bet that the same pre-hardener step wouldn't apply.

I'm going to go back to my previous plates and see if they do better than these new ones.

Thanks guys!

[Ed Wesly]

BobH said “Finally, Hans Bjelkhagen recently mentioned somewhere that PFG-03C should NOT go black immediately in the developer as was mentioned by Larry and has been my experience too. He said that if it does, it means the material was fogged by being passed through x-ray scanners coming into the US, and is therefore damaged. I think that may be also true of the PFG-03M material you're using.”

Recently having dinner with Hans and Stas from Geola they said the fog was coming from the very tiny grains being oxidized by the atmosphere, rather than X-ray fogged! Like tarnished silverware!

In any case, if you want to salvage the fogged plates, try the Jeff Blyth “erasing” formula in this forum’s Wiki somewhere.
When I tried the PFG-03M plates, I did develop and bleach, however my best results came by using the GP-2 developer, whose chemistry is given on the Geola or Slavich web site.
Also, TJ (Dr. Tung Jeong, founder of Integraf) told me that he uses a dunk in cold water, room temperature or below, instead of the hardener to help keep the emulsion on the plate during processing.

I had written a poster paper for the 2000 ISDH comparing some left over Agfa plates, Slavich PFG-01 and -03M, and Colour Holographics BB640 plates. Anyone want a copy of it please PM me c/o this forum. My conclusion: Don’t screw with the Slavich junk, just go BB and you will be very happy!

[BobH]

Could be my memory's been fogged by W-rays! :whistle:

But fogged film is still fogged film, which isn't as bad as fogged plates like the two boxes I have in the fridge.

[JohnFP]

A very simple test would be to develop a completely unexposed plate. If it goes black fast then it's definitely fogged.