Re: Paper negative
On Tue, 4 Dec 2007, email@example.com wrote:>
Judy's mineral oil was bought for something or other in the studio, I forget what... but it's labelled "Heavy Mineral Oil (intestinal lubricant)" and I believe essentially the same as "Castor Oil," which has the same function. But when I was testing all the ways I could think of for transparentizing paper negatives I tested the mineral oil, among others.I think I have it now. Judys mineral oil is 'paraffin wax', your mineral oil is our 'liquid paraffin' and 'baby oil' is refined mineral/paraffin oil...
My findings (written up in Post-Factory #8) were quite different from Katharine's, perhaps because our instruments are different or our oiling process was different.... but I found with the mineral oil just what I found with the other methods using wax or oil.... that the densitometer reading on day one, INVARIABLY and INEXORABLY rises, starting on day 3 or even day 2, until (theoretically anyway) the paper could in time be as opaque as it was when you began.
The bees wax reverted the least & most slowly.
(However, I didn't test every paper with an actual print on the various days, so.... possibly mysterioso-- maybe the densitometer is harder to please than the emulsion. That is, it strikes me as unlikely, but still possible, that the negative will print the same or nearly so, even as the densitometer reading changes.... Is this crazy?)
Parrafin (the hard wax, that comes in blocks, the kind they use to wax ski's) reverted more slowly, and bees wax reverted least of all. I haven't energy left tonight to re-read my article, tho I'll try tomorrow... but my findings in general were that if you wanted to re-use a paper negative after a long hiatus, you did well to re-wax it.
One other use I found for mineral oil, btw, was thinning makeup. From being either too vain or too lazy, or both, I rarely use makeup, so the "Cover" I have for camouflaging the family trait of dark circles under the eyes hangs around for years and dries out. Reading the ingredients on the label, one day, I noticed "mineral oil." So I poked holes in the caked stuff with a toothpick, poured a little mineral oil over it and mixed. After sitting for a couple of days (the makeup, not me), it was like new.