Re: Paper negatives- Ink Selection
Since the original post questioned the list on their ink settings I did another comparision: my previous post gave MY exposure times in MY setup using oiled and un-oiled paper using a colorised negative, so I now did a furter test, again with cyanotype (cheap and quick) using Chartthrob. A Grayscale_Chart printed with a color 0;255,21 printed OK with an exposure of 8 mins (ChartThrob white at 2, black at 100). A Grayscale_Chart printed with All Inks needed an exposure of 24 mins to arrive at the same density/tonal scale (ChartThrob white at 2, black at 99). Funny enough the resulting curves were almost identical. I print with an Epson 1290 using third party inks on Epson PQP oiled. So does a correctly colorised negative aid in more speed when printing? For me, maybe yes, but an all inks setup might be (a lot) cheaper, especialy when using Epson single-color cartridges Guido 2008/10/14 Loris Medici <mail@loris.medici.name>: > Katharine, don't worry I'm pretty careful about this subject - knowing (by > experience) you'll chime in every time it's brought up, to clarify ;) I'm > getting older I guess; less and less surprises... ;) > > I wasn't attributing the short exposure I'm using to curves at all, that > was a side note (which should have been enclosed between parenthesis, > sorry). I was trying to say (indirectly) that since the DR (=density > range) and tonal progression of my paper negatives (made with the HP 9180 > all-inks grayscale setting, using the printer's plain paper profile) are > close to ideal (in tricolor gum printing context - which is supported by > the fact that the curve I devised for this particular combination is the > smoothest and least dramatic one among all curves I did until now), > therefore, other people's longer exposure times could be caused by the > fact that they're using negatives with more DR, which naturally will > require more exposure and a stronger / more dramatic curve to > counterbalance. Or they're not calibrating, or their calibrations are > flawed... > > Hope it's clear, and makes more sense to you now. I perfectly understand > the confusion I may have caused on your part. > > Regards, > Loris. > > P.S. BTW, I have compared my times with the times of people who use > similar light source, emulsion, negative media and working procedures. I'm > perfectly aware of the parameters affecting exposure time and pay > attention to them. > > > 14 Ekim 2008, Salı, 7:18 pm tarihinde, Katharine Thayer yazmış: >> >> Loris, I'm wondering what data you're basing this last bit on, that >> other people's exposure times are longer than yours. It's generally >> not useful to try to compare exposure times because there are so many >> variables involved, but putting that aside for a moment, I've looked >> back through this thread, and the only reference to exposure times I >> can find is Guido's comparison between oiled and unoiled Epson PQ >> paper, 8 vs 48 minutes, with cyanotype. Since it was cyanotype, and >> since the paper is a heavier paper (27 pounds) than yours, it's not >> surprising that his exposure time for unoiled paper would be longer >> than yours, and we haven't even got to light source yet; to reach >> immediately to curves to account for a difference in exposure times >> seems rather a long stretch to me. >> >> Perhaps I've missed other posts that included exposure times for gum >> and paper negatives (my server doesn't accept some of the alt-photo >> mail, so I don't always see all the posts). At any rate, my times >> with oiled paper negatives run close to my times with inkjet >> transparencies, about 3 minutes, to add to your database on exposure >> times. I don't have any comparison with unoiled paper to offer, >> because that's not an option that makes any particular sense to me. >> >> But be that as it may, I can't see any reason why curves would >> account for a difference in exposure time. After all, the exposure >> time is determined before curves are even calculated, at least that's >> how it is with the system I use, and I assume it's the same with all >> systems; the curve doesn't change the exposure time. Besides, curves >> simply redistribute the tones within the print tonal range that >> particular emulsion can print under that particular protocol; they >> don't extend it, so there's no logical reason curves would have any >> effect on exposure time. >> Katharine >> >> >> On Oct 12, 2008, at 11:23 AM, Loris Medici wrote: >> >>> I use the grayscale using all inks (not black and gray - if present >>> - inks >>> only), plus, I choose plain paper as the media. Fortunately, with >>> my inks >>> the printer lays just enough ink giving an almost perfect negative in >>> terms of density range (something around log 1.0), and the curve I >>> use for >>> gum prints are is the least drastic and most smooth one among my >>> curves >>> collection for many processes and paper. In fact, I think that's >>> why other >>> people's exposure times are considerably longer compared to mines... >>> (!? > >
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