Sunday, February 14, 2010

Updates on the Three Main Things

New55 has narrowed down areas of worry to three:

1. Emulsion. New55 identified more than one emulsion that can be processed in two minutes using a reagent. The results to date are contrasty and have some other problems, but are an excellent start. Even TMY can be processed in two minutes if one is aggressive. The image of the rocks at the beach is somewhat unfair, as the speckled texture gives the impression of more grey scale than was actually achieved, but it is still an interesting result. So-called "monobath A" produced quite smooth tonal gradients when camera was aimed at the bench, and its shadows, but took longer.

Scroll down or look at earlier posts to see these examples.

2. Reagent. There are several reagent options, of which two have been tried. Both do something, did not cause fires, nor were they difficult to make. Images are posted below. There are many different possible ratios possible just using the Type 55 reagent information we have from the MSDS. If someone could assist in tweaking, or simply remembering, that would save a lot of time and money. It occurs that a very aggressive reagent could be made with materials never used by Polaroid.

3. Receiver sheet. New55 Project considers this essential for controlling the rate of silver diffusion from the negative if processing times are to be short enough to label "instant". I think, personally, that two minutes is the limit but if it had to be a little longer and the results were very good then I think that might be OK. Not everyone agrees. In any case we do not have enough information about the nucleation and migration kinetics with respect to reagents and receivers, and are seeking advice and help.

In other words, we still have no real info on how the receiver sheet will be prepared, especially the non-coaterless 55 type receiver sheet construction, which we suspect is very much like the old 47 and the like, with that wonderfully scented pink coater swab that prevents browning. The FP100B material is being looked at, but it is not like 55. Chances are this is something simple and we will look stupid soon.

Things like packaging and how actual processing will be carried out are being left open right now, as there are several options beyond existing roller and pod methods. Roller and pod have not been ruled out by any means.

1 comment:

Bob Crowley said...

Silver Diffusion book by Rott of Agfa is on the way from Amazon. Rott at Agfa was the inventor of the silver diffusion transfer positive which was the cornerstone of Polaroid. His discovery, which apparently was a surprise, came about while experimenting with monobath processes. Rott should be celebrated for his invention, which predates Polaroid. Land then used the Rott principle, and refined it by using a sheet and roller system that became the 47 film and similar types.

A link to Rott's patent is posted in the early pages of this blog, and is essential reading for anyone interested in the history of Polaroid.