On Thu, 21 Oct 2004 Ender100@aol.com wrote:
> With your oiled negatives, is it possible the oil oxidizes or turns rancid
> and cloudy? It wouldn't surprise me that oil would take a lot longer than the
> inks to dry.
There is this myth that the oil turns rancid, tho I never found it to
happen. I even came across the claim in a magazine of the '30s -- which
isn't to say it can't happen, but none of the oils I tested said
refrigerate after opening -- and as I say it didn't happen.
I imagine that it was oxidizing, and when it fully oxidized the density
was close to the original unoiled densitiy. As for "cloudy" -- the
original unoiled paper was cloudy, but when the oil dried it wasn't any
cloudier, or not that I detected. But then I wasn't looking for that. All
I was looking at was the fact that an oiled paper negative wasn't stable.
A beeswaxed negative was stable.
I do know that many custom printers (giclee printers if you are
> from France) cure their prints done on matte papers for about 24 hours.
> They use a light paper interleaved between the prints and they report that a
> latent image of the print will appear on the interleaf papers due to the
> evaporation of the ink/carrier. I think that would be a pretty good estimate. With
> Pictorico OHP film, you can see the drying process if you hold the negative
> right in the light—it's milky looking and then clears as it dries. I like to
> sit and watch them dry—sometimes I take them out on the front porch and dry
> them there so I can sit in my rocking chair.
> Mark Nelson
> Purchase the book @
> Credit Card & Paypal now accepted
> In a message dated 10/20/04 10:32:43 PM, email@example.com writes:
>>> Mark Nelson said:
>>> Regarding waiting for negatives to dry. On Pictorico OHP film usng the
>>> Epson Ultrachrome inkset (and I am sure this is also true of other inks
>>> substrates), You can take UV readings of the negative with a UV
>>> densitometer after
>>> it comes out of the printer and watch the UV density drop over a period of
>>> time—up to a couple of hours or more. It's not just an issue of whether
>>> will smear if you use the negative right away. It is extremely important
>>> negatives be "cured" after printing so that the UF densities of the inks
>>> stabilize. Otherwise you are not going to get consistent results when
>> Mark, for how long a period did you test exposure time?
>> I realize these are two different things, but still the thought comes to
>> mind -- I found that oiled paper negatives dried for about a month. I
>> don't remember the exact schedule, but something like that -- and when
>> they did stabilize they were much less translucent than they'd been at
>> first, in fact, if memory serves, not that much better than unoiled paper.
>> Is it possible the inks behave something like the oils? Are those
>> negatives good indefinitely once they're "stabilized"?
Received on Thu Oct 21 22:41:30 2004
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