Film probably just needs far less washing than fibre based paper. Remember that your sheet film is made of pretty water impermeable polyester, versus the water soaked and contaminated paper base of a fibre based print. That probably makes a huge difference..., as the gelatin layer on the film base is just a tiny layer.
Originally Posted by Usagi
"The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true.
" - William M. Ivins Jr.
"I don't know, maybe we should disinvent color, and we could just shoot Black & White.
" - David Burnett in 1978
"Analog is chemistry + physics, digital is physics + math, which ones did you like most?
That's very true. I have to check how final wash with only couple of water changes will work with gelatin based roll films. Perhaps they will require a bit more water.
Originally Posted by Marco B
Time will show
yes! thanks for posting here is some more food for thought…
Originally Posted by amac212
Food for thoughts.
Sorry, it's in French.. But I'll describde it the best I can do !
Explanation is not given, only results..
Two parts :
-a table, with chemical additives ranked by efficiencies (hydrichloridyc acid is the worse and sodium hydroxyde the best)
-a graph showing effect residual log of hypo concentration on paper (mg/m²) vs cocnentration of the added chemical.
What can we learn :
Tap water wash better paper than distilled water.
Other compound can make a wash more efficient.
(aside, one should take into account side effect : sodium hydroxide is not good for your print
Please note the pH values. These affect swell and thus wash rate. The most swell also causes degradation of the emulsion due to the high pH. So, things are not always as they seem. More tests should be shown in order that the entire story is rounded out.
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that's has been the ccommon wisdom for decadesbutyes, worth restating.nevertheless,I thought HT2 was a washing efficiency test for paper but not for film;I've used HT1 for film so far
Originally Posted by nworth
Last edited by RalphLambrecht; 01-25-2014 at 02:13 PM. Click to view previous post history.