Re: Dense or Density

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From: Carl Weese (cweese@earthlink.net)
Date: 11/26/01-06:53:52 AM Z


Clay,

ABC+ appears to have a fairly short "window" of shelf life. It needs to be
aged some days before use, and then used in a period of a few months.
Missing the window can result in high fog from what I've heard though I
never encountered it. Since I work in trays I use PMK which has a long shelf
life. For rotary, Sandy's Pyrocat may be a better choice. I plan to test it
soon for tray processing of big negatives.---Carl

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---------- >From: clay <wcharmon@wt.net> >To: alt-photo-process-l@sask.usask.ca >Subject: Re: Dense or Density >Date: Sun, Nov 25, 2001, 9:12 PM >

> I've had the same problem with Rollo Pyro (ABC+) resulting in incredibly > long exposure times although I use mostly TMax 400 and TriX. I get a very > high base+fog using the technique outlined in the Weese article in Photo > Techniques with the Rollo Pyro. For what its worth, I DO NOT have the same > problems with Sandy's Pyrocat-HD, but do agree that adding an extra stop of > exposure (just in case) is a very bad idea with Pt/Pd printing in mind. In > fact, the whiz-bang analysis tools in the BTZS plotter program indicate that > my actual film speed with Tmax 400 and Pyrocat-HD is actually around ISO > 600. > > I have been advised (but haven't yet tried) that skipping the second, post > development metaborate bath with Rollo pyro will reduce some of the high > degree of overall staining you seem to be getting. I'm going to give that a > shot this week now that I have some time and curiosity to do a little > investigation into the staining problem. I'll let the list know if anything > earth shaking results. I CAN say that the Pyrocat-HD has pretty much solved > the problem for me though, and it seems to give all the benefits > attributable to a pyro developer (e.g. high acutance, great highlight > definition, actinic filtering for UV sensitive processes, and reasonably > short development times) without the high base+fog and toxicity. Check out > www.unblinkingeye.com for the formula. It is incredibly cheap and easy to > mix yourself. > > Good luck. Just wanted to let you know that you are not alone in finding > this difficulty with Rollo pyro. > > > Best, > > Clay > ---------- >>From: Jeff Buckels <jeffbuck@swcp.com> >>To: alt-photo-process-l@skyway.usask.ca >>Subject: Re: Dense or Density >>Date: Sun, Nov 25, 2001, 7:28 PM >> > >>OK: I've been making the FO the night before and actually using it late morning >>or so the next day.... The ambient humidity lately has been 30 to 40%. Before >>coating, I humidify the paper (Platine) in front of a smallish sonic humidifier >>for about a minute. After coating, I dry the paper (cold air double window fan >>at four feet dries to 75% or so, then med-heat hair dryer till dry), then >>re-humidify as before, then expose. The range has been pretty good, but not >>great -- I'm not getting to real black black (brown brown). I used sodium >>dichromate just with this one print; mind you, the brightness range of the >>subject was a good stop short of normal. I exposed and developed normally, >>figuring to kick up the contrast a bit with the sod dichromate. This worked >>pretty good. It was not full range, but I intended the look I got (pretty much) >>from the get-go. Believe me, if the exp. time hadn't been 50 minutes, I >>wouldn't have thought there was a "problem"... I've only done two non-pyro >>negatives. The exposure times were well within normal ranges, around 5-7 >>minutes.... Finally, these pyro negatives that have printed so slow in pt/pd >>are correspondingly slow on Azo. For this reason, I think we can eliminate bad >>FO or bad pt/pd or bad humidifying etc. ... I sure appreciate these responses. >>-jb >> >>Eric Neilsen wrote: >> >>> Jeff, There seems to be many things left unsaid by you about your whole set >>> up. >>> >>> FO should be well mixed and will take hours (pushing it) and a day or so to >>> fully dissolve. It will last many many months. Mixing it fresh is a >>> problem, not only to get it mixed, but weight properly the same for small >>> batches. If you are using AFO, that is a different animal. >>> >>> Are you drying your paper? dry palladium paper or one with a low RH is >>> slower than a humidified paper? >>> >>> Is the film printing full range? 80 minutes seems quite long. How much >>> dichromate in your developer? this will also slow your print times. >>> >>> What are your times for a non pyro negative? >>> >>> EJ Neilsen >>> >>> ----- Original Message ----- >>> From: "Jeff Buckels" <jeffbuck@swcp.com> >>> To: <alt-photo-process-l@usask.ca> >>> Sent: Sunday, November 25, 2001 10:04 AM >>> Subject: Dense or Density >>> >>> > Hello from Albuquerque NM. This is my first posting to this fine >>> > list.... >>> > >>> > I've started doing platinum/palladium. Have done two sessions in my >>> > newly up and running home rig. I'm excited by the results I'm getting >>> > but am plagued by preposterously long exposures. Here's what I do: I'm >>> > shooting FP4+ (5x7 and 8x10) @ EI 64, erring on the side of >>> > over-exposure. Nothing fancy as to reading; for the time being, to keep >>> > it simple, I'm just doing split readings (mostly between the darkest and >>> > lightest readings on the palm of my hand), leaving any particular >>> > contrast control to the printing stage. I'm developing the film in PMK >>> > for 12 minutes at 70F. All exposures, regardless. The printing is on >>> > Platine. I've done a couple prints with pure palladium, a couple with >>> > about 55/45 Pt to Pd, adding some contrast on one occasion with a small >>> > amount of sodium dichromate in the pot/oxalate developer. The color and >>> > contrast need tweaking but I'm happy with both. The exposure times are >>> > an outrage: From 20 to 80 minutes. I can live with 20, and I >>> > understand there's only 2 stops difference between that and 80, but most >>> > the exposures are over 50. The light source is a new "oven" from >>> > Edwards, which I feel is working correctly. Can anyone tell me if >>> > anything jumps out of the above procedure as the likely repeat cause of >>> > these pokey exposures?? I'd sure like to stick with Pyro and know that >>> > that is the principal culprit. But, you know, if I could just get to >>> > 15-20 minute exposures, I'd be satisfied.... Thank you. >>> > >>> > jeff buckels (albuquerque nm) >>> > >>> > >>


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