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Photo Forum / Film Photography / Darkroom / February 2006bad neg msytery
I just posted this note on the large format group as it involves 4x5 negs developed in a traditional darkroom. In the past few months I have printed two or three images from 4x5 negs that have many very small white spots on the 16x20 print. The negatives show that the black neg spots are not "on" the neg like dust spots, but exposed onto it. Yesterday I made two bald sky exposures, one with my 210mm and the other with my 150mm as I'm sure the trouble negs were exposed by one of these lenses. The 210mm showed a hundred or more tiny black spots. But only two hours before I shot some still lifes with this lens, developed all negs at the same time in the same chemicals and those negs were perfect. The film is Kodak Tri-X 320 TXP film purchased within the last year. I always expose with an f-stop in the mid range, neither wide open nor with a very small aperature. The problem seems to be bad film, but randomly appearing from the same pack. Or am I missing something? Any ideas? Art Did you use acid stop bath? > I just posted this note on the large format group as it involves 4x5 > negs developed in a traditional darkroom. [quoted text clipped - 12 lines] > something? Any ideas? > Art > I just posted this note on the large format group as it involves 4x5 > negs developed in a traditional darkroom. [quoted text clipped - 12 lines] > something? Any ideas? > Art Could it be you are printing with condenser lamphouse and the condensers are dirty? check the negative for black spots.  Signature"To announce that there must be no criticism of the President, or that we are to stand by the President, right or wrong, is not only unpatriotic and servile, but is morally treasonable to the American public."--Theodore Roosevelt, May 7, 1918 greg_____photo(dot)com > I just posted this note on the large format group as it involves 4x5 > negs developed in a traditional darkroom. [quoted text clipped - 12 lines] > something? Any ideas? > Art Pin holes in your bellows, just thinking if the still life shots were indoors and the problem negs where shot outdoors. dschneller@sympatico.ca spake thus: >>I just posted this note on the large format group as it involves 4x5 >>negs developed in a traditional darkroom. [quoted text clipped - 14 lines] > Pin holes in your bellows, just thinking if the still life shots were > indoors and the problem negs where shot outdoors. Nope; pinholes will fog the film, or give large spots, not tiny ones as he described. (Think of the cone of light between the pinhole and the film.) SignatureIf the United States government, with all its capacity to collect and interpret information, did not see Hamas doing very well in the Palestinian election in the wake of these other Islamist victories, then it is either willfully blind or totally incompetent—- and neither possibility is a very comforting thought. - Rami G. Khouri, editor at large of the Beirut-based _Daily Star_ > I just posted this note on the large format group as it involves 4x5 > negs developed in a traditional darkroom. > In the past few months I have printed two or three images from 4x5 negs > that have many very small white spots on the 16x20 print. This happened to me a few times when I went to water rinse instead of acetic acid stop bath. When I went back to using acetic acid stop bath, the problem disappeared. > The negatives > show that the black neg spots are not "on" the neg like dust spots, but [quoted text clipped - 9 lines] > something? Any ideas? > Art I use HC-110 developer and yes, I use an acid stop bath. Note: I'm not talking about printing, the black spots are on the negative after developing it. Art > > [quoted text clipped - 26 lines] > > Hmmmmmmmm.................. Try new batch of film.... Do you use trays? Try tank and hanger.... > I use HC-110 developer and yes, I use an acid stop bath. Note: I'm not > talking about printing, the black spots are on the negative after [quoted text clipped - 26 lines] > > > > > I use HC-110 developer and yes, I use an acid stop bath. Note: I'm not > talking about printing, the black spots are on the negative after > developing it. > Art Its either the film or Art it could be the holder, your using sheet film I believe you said. In any event way back when I first started using sheet film I had some old holders, and they had small pin sized scrapes on the metal....I used a sharpie to blacken the places. Signature"To announce that there must be no criticism of the President, or that we are to stand by the President, right or wrong, is not only unpatriotic and servile, but is morally treasonable to the American public."--Theodore Roosevelt, May 7, 1918 greg_____photo(dot)com You could be dispersing some kind of contaminant onto the film somehow. Photo chemistry powders can become airborne dust and settle on your film at some point. Just raising the possibility... > I just posted this note on the large format group as it involves 4x5 > negs developed in a traditional darkroom. [quoted text clipped - 12 lines] > something? Any ideas? > Art >I just posted this note on the large format group as it >involves 4x5 negs developed in a traditional darkroom. [quoted text clipped - 15 lines] > something? Any ideas? > Art This is pretty puzzling. Have you examined the spots with a strong magnifier. Check the surface of the film. This might tell you if there was a coating problem. I very much doubt that its due to out gassing as was suggested by another poster. Outgassing in acid stop bath happens only when the developer contains carbonate, which HC-110 does not. In any case, it does not seem to be problem with modern films. I can't think of anything that would produce _sharp_ black spots on negatives. Almost everything, pinholes in the camera or reflections from something, produce blured spots. Perhaps the holder dark slide has holes in it but I've never seen such a thing and it would probably produce streaks not spots. I don't suppose you were using a focal plane shutter. Signature--- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com Taking an unexposed sheet DIRECTLY from the pack (open a new one) and processing it is the only way I can think of to determine whether defective film is involved or not. > >I just posted this note on the large format group as it > >involves 4x5 negs developed in a traditional darkroom. [quoted text clipped - 36 lines] > Los Angeles, CA, USA > dickburk@ix.netcom.com Thanks for all the thoughts. I posted my original note on rec.photo.equipment.large-format also and received a really outstanding reply, fairly lengthy, which I recommend reading for everyone. It's the one from Michael Gudzinowicz. I've tightened up my development procedure following his suggestions but think he may have hit on the problem I outlined since I seem to be in good shape on his other ideas. He suggests inadequate agitation during fixing. Inadequate? I don't agitate at all except for a lift or two on the film holders during the eight minutes of fixing (he suggests 10 minutes). I'm also adding some alcohol to the Photoflo for the final rinse. But I think all his suggestions are worth looking at for anyone developing film. These newsgroups sure pay off! Art >Taking an unexposed sheet DIRECTLY from the pack (open a new one) and >processing it is the only way I can think of to determine whether [quoted text clipped - 49 lines] > > You should agitate vigorously during fixing. Why have you not been doing this? > Thanks for all the thoughts. I posted my original note on > rec.photo.equipment.large-format also and received a really outstanding [quoted text clipped - 57 lines] > > > > Because I missed this step during the workshop I took from Barnbaum. I looked at his book, the most recent edition, and found his instructions, not underlined by me as are many other instruction passages. He says agitate two or more minutes and fix for a total of 7-10 minutes. So the instructions are there, I just missed them. But I'm going with 10 minutes of continuous agitation as advised by the poster I mentioned. Also, I never had a problem through 300+ negatives so wasn't motivated to research and learn the right way. Art >You should agitate vigorously during fixing. Why have you not been >doing this? [quoted text clipped - 78 lines] > > 1. Use Rapid Fixer 2. Agitate vigorously 3. Fix 3-5 minutes, no more > Because I missed this step during the workshop I took from Barnbaum. I > looked at his book, the most recent edition, and found his instructions, [quoted text clipped - 75 lines] > > > > I was plagued by "white spots" despite using all filtered water & chemicals. I reprinted and lo' and behold, more spots, but in different locations on the paper. It's was the papers fault. I now use a premier paper, but once in a while a couple of spots. Ray >I just posted this note on the large format group as it involves 4x5 negs >developed in a traditional darkroom. [quoted text clipped - 12 lines] > something? Any ideas? > Art |
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