BB-640 vs PFG-03M

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Updated: 2005-03-28 by HoloM (the god)
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Ted Park

BB-640 vs PFG-03M

Post by Ted Park »

Hi,
Has anyone had experience with both these photoplates? I've been using the slavich plates, but I'm wondering if the colourholographics plates are better.


--Ted.

Dinesh

BB-640 vs PFG-03M

Post by Dinesh »

"Has anyone had experience with both these photoplates? I've been using the slavich plates"
I've used both. My experience is that the BB plates are incredibly clean, but incredibly insensitive. They need presensitization. Also, I don't seem to get them super-bright, necessary since I'm doing DCG. This may be due to processing. I use CWC2 with a PBQ (rehalogenating) bleach. The fact sheet that came with them when they were HRT suggested a metol-ascorbic acid developer and Van Ranesse bleach.
I can get Slavich (VRP-M) very, very bright but a little noisy. I didn't get good results with a reversal type bleach. Also, the drying method varied. i found that drying Slavich in alcohol tended to kill the hologram a bit. I now dry in photo-flo.
To me the advantage of the brightness overcomes the noise, especially since I can control the reproduction of the noise.
Tom B.

BB-640 vs PFG-03M

Post by Tom B. »

I like the BB-640 plates better. Much cleaner and more consistent results - the emulsion is much less soft and runny than PFG03. As Dinesh states, the plates are relatively insensitive - even with presensitization I need at least a milliJoule per cm^2 for reasonable density. For non-color shifting presensitization I've found a 1% ammonia presoak works for me, and TEA for color shifts. I use JD-4 developer (metol-ascorbic) and Fe3 rehalogenating bleach (Brilland). A minor additional advantage is that drying time is much faster than for PFG-03 - tens of seconds rather than tens of minutes.
Tom B.

BB-640 vs PFG-03M

Post by Tom B. »

I should also have mentioned that my BB plates have been coming from Vinteq
http://www.vinteq.com/gen-bb.htm
He often has stock of 4x5 640 plates and is willing to ship by mail which was a big plus for me since I prefer to avoid UPS whenever possible.
Ted Park

BB-640 vs PFG-03M

Post by Ted Park »

It sounds like the BB-640 is very good media. Can it be bleached with the standard JD-4 bleach? I've never presensitized plates, so this would be a new addition to my process.


Tom B.

BB-640 vs PFG-03M

Post by Tom B. »

The JD-4 (copper sulphate) bleach should work fine. I am habituated to ferric sulphate bleach, but whenever I've tried both with other films, they produced equivalently bright results. I think the deciding factor for me was that I preferred the slight yellow brownish stain of the ferric bleach to the bluish copper sulphate stain. Also there may or may not be some concern about possible printout (light-induced darkening) with copper sulphate - I have never directly compared printout sensitivity of the two.
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