Re: ferri sesquichlorati
Hi Francesc If what you are looking for is highest sensitivity, that is usually given as 365 nm (I believe something in that area goes for most metals ? Although several factors affect things... As usual) I don't have everything here right now, for me this has been more background studies.. Just very quickly put together, this is from something I did some years ago, the top line shows the absorbency of ferric oxalate (in water), the following lines/scanns are "during" exposure, each line, moving downwards, is a doubling of exposure time. http://photorelief.googlepages.com/ferricoxalate I´ll take down that link in a week or so, are very slowly working on that site... (and before anyone asks, no; alcohol sensitisation of platinum printing is not very practical, as the alcohol tends to evaporate :-) Ammonium ferric citrate and oxalate have an almost similar absorbency pattern. (and absorbency does not directly equal sensitivity). Try google scholar, that would give better results for that kind of searches, but a university library connection might help to actually get hold of the search results. I can recommend a couple of articles on this subject, but they are quite heavy reading and are not about printing, contact me off list if that is your taste :-) Halvor On 10/25/06 3:25 AM, "sitgesn1@netscape.net" <sitgesn1@netscape.net> wrote: > Halvor wrote: > >>> But yes, the most impressive part of ferric chloride is its low > sensitivity :-) > (don't think 488 nm would be the optimum for ferric really, have done > some spectral scanning of AFC and FO and don't think there was much > absorbency at least, in that area, but I am not too familiar with the > needs of holography<< > > Halvor > I'm very much interested in ferric printing processes using ferric > salts.I have been trying to find through google ferric absorption bands > between 250-500 nm but without succes. I understand after reading > above paragraph you probably have these data. Should it be possible to > get a copy of ferric salts absorption bands? > -Francesc > > > ________________________________________________________________________ > Check Out the new free AIM(R) Mail -- 2 GB of storage and > industry-leading spam and email virus protection. >
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