PFG-04 Processing

This is a forum to share experiences and ideas about holography.
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mrneilalan

PFG-04 Processing

Post by mrneilalan »

I'm an experienced holographer with silver plates, but I have not tried DCG. I'm interested in working with the Slavich PFG-04 plates. I'm getting some conflicting information about processing though. The "preferred method" says:

1). Thermal Hardening after exposure (100 degrees C) - Depending on the layer freshness.
2). Cooling to Room temperature.
3). Bathing in running filtered water - 3mins.
4). Bathing in 50% Isopropyl Alcohol solution for 2 - 3 mins.
5). Bathing in 75% Isopropyl Alcohol solution for 2 - 3 mins.
6). Bathing in 100% Isopropyl Alcohol solution for 2 - 3 mins.
7). Drying in a desiccator. (100 degrees C) for 60 mins.
8). Emulsion layer preservation using optical anhydrous adhesive and protective glass.

But I've also been told that I can use Kodak Rapid Fix and place of the 100 degree hardening. Does anyone have any experience processing the PFG-04 with Rapid Fix?? Do I still need the desiccator in STEP 7? I have access to a desiccator, but it is not heated. What do they mean 'drying in a desiccator (100 degrees C)'??

Any help that the community can give me would be appreciated.

Neil
Joe Farina

PFG-04 Processing

Post by Joe Farina »

It seems that few people who frequent this forum actually use PFG-04. I haven't tried it myself, so my comments will assume that this material is similar to "regular" DCG.

There are a number of methods to "develop" DCG, such as heat, light, and fixer. All of these methods help the exposed areas get extra reduction (to Cr3, which causes the needed hardening) and all of the methods will also likely provide some extra "bias" hardening to the entire layer (i.e., to the unexposed areas also).

Since Slavich recommends heating, I would give that a good try, first. If that fails, then you could experiment with something else, like fixer.

After you produce the holograms, it's important to thoroughly dry the layer, i.e., desiccate it. The drier you can make it, the better. Any excess moisture remaining in the hologram will increase the likelyhood that it will absorb additional moisture from the air, and cause it to vanish. I doubt there's any special need to use a "desiccator" as Slavich suggests, a more common approach is to use ordinary heating for maybe a couple hours or more. You could also try a microwave oven (being careful not to overheat the glass in this case, because it can crack) or a desiccator. Some people even use vacuum ovens at this stage.
JohnFP

PFG-04 Processing

Post by JohnFP »

Hey Neil, welcome to DCG. From what I heard the Slavich PFG-04 is so old you will probably not get super bright results. But you surely should be able to get nice holograms. There is nothing special about Slavich DCG other then they adjust the PH to allow a longer storage time. So you should be able to use Rapid Fix with hardener in place of the heating. I have never been crazy about heat developing as there seems to alway be a little unconverted CrVI left in the emulsion after heating. This means you have to really wash the hologram for a long time (I found) to remove it all. And then where the heck does it go? Remember this is nasty stuff when in the CrVI state. Fixer always converted all the CRVI to CRIII which is harmless. Again, this is just my opinion for safety and environmental reasons. It cracks me up they tell you to bath it in running water with all that unconverted Cr going down the drain :naughty: and again, I have found it to take much longer then 3 minutes, more like 10 - 20 minutes. Once you bake that stuff, it's hard to get the orange out.

Instead of desicating you could blow dry with a hair dryer, hot, on high and as close as possible. Really dry the heck out of it. I still have plates I dried this way and they are uncovered, over 2 years old and still have not faded. Of course I surely would recommend using a cover plate to protect the final hologram from moisture if you want to keep it for years.

Finally, they tell you not to exceed 20C for fresh layers. I am sure yours is over a year old so if you can up the temp of your water rinse and alcohols, that will help get a brighter hologram and maybe even force it into the broadband playback a little.

Good luck and keep us posted. Lots here love to help.
mrneilalan

PFG-04 Processing

Post by mrneilalan »

OK. Great advise on processing. I have already purchased Blue Ray Diodes to use in my rig, but I've just read that coherence is a major issue with these diodes. Can you recommend a laser for DCG exposure? I'm looking for something that I can find on EBay. I use spatial filters to clean up and diverge my HeNe lasers in a sandbox setup. Again - thanx for your input.

Neil
JohnFP

PFG-04 Processing

Post by JohnFP »

Have you looked at the lasers on this forums for sale page? Chances are if you buy from a holographer the laser would be holography ready. I would suggest anything over 100mw in the green or over 20 - 30 mw in the blue for DCG at a minimum to keep exposure times reasonable. Dave Baton usually has very nice holography ready lasers for sale.

Dave?

If you have three phase power available I can sell you an Argon Ion laser. It puts out about 600mw in the green or blue (with elalon). It's color tunable and the coherence length is in the meters. :wink:
The_Stranger

PFG-04 Processing

Post by The_Stranger »

JohnFP wrote:H Dave Baton usually has very nice holography ready lasers for sale.

Dave?
Do not hesitate to buy from Dave, he always offers a lot for a nice price and has helped me a lot when I bought a HeNe laser from him...
dave battin

PFG-04 Processing

Post by dave battin »

thanks for the words of endorsement ! i currently have 215m laser putting out @30mw with a varible power control dongle (not in picture), controller, power supply and all the necessary heat sinks and connection wires to power this unit. $475 guaranteed satisfaction too! as a holography forum member i'll throw in some extra "goodies" too ..........
Attachments
OEM 215 30mw
OEM 215 30mw
215m30e.JPG (217.17 KiB) Viewed 3212 times
JohnFP

PFG-04 Processing

Post by JohnFP »

Hey Dave, what are the exposure times for DCG on a 4x5 plate, SBR with 30mw of 532nm?
dave battin

PFG-04 Processing

Post by dave battin »

good question John. im thinking if its a bright object doing a denisyuk? @5-4 min exposuer, we will see this weekend as im going to mix up a batch later today .............
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