Dust on LF Negativesgreenspun.com : LUSENET : Large format photography : One Thread
mostly i shoot b&w negatives in 8x10. in the meanwhile i succeded in eliminating the scratches from developing the negatives in trays (5 to 10 at a time), but i still cannot get rid of the dust!!! i shoot exclusively outside in the field and carry my filmholders in a separated closed bag. when loading the film i use antistatic towels and air to clean the holders, moreover there is no difference if i load the film in a tent or in the darkroom, there are always some dustspots on the developed negatives. maybe somebody can give me some advice rgds herwig prammer
-- Herwig Prammer (email@example.com), May 09, 2002
1. Try to find a used Zone VI anti-static brush. It runs on 110v and was manufactured by Chapman = the sticker says Chapman Power Supply - in addition to having a Zone VI sticker. You may be able to find one on ebay (2 were listed within the past two weeks). The unit creates an anti static charge that repels dust from film holders - and whereever you decide to use it.
2. If you cannot get rid of dust get a small jar of opaque red. With a very fine brush spot the clear areas (where you had dust) on your negs. After making your final print you can Spottone the areas to match the print color. This works better than scraping black spots of the final print.
-- Per Volquartz (firstname.lastname@example.org), May 09, 2002.
Hi, i am very interested in this topic , because it is very frustrating to see good shots being "tainted" by this damned white spots in the negatives that inesorably allow light to go through freely.... So, this is for Per Volquartz, : Per , what kind of red paint do you use? Acrilic?
-- domenico (email@example.com), May 09, 2002.
Apparently Kodak discontinued "Opaque Red" last year (I must be lucky = have two jars left...). However, Retouch Methods = the company that makes Spottone makes a similar product called "Opaque Black"...
Kodak's product (and I assume that the similar product made by Retouch method's) is an opaque water color that can be re-wetted and removed. In addition it is extremely finely ground and goes down very well on a negative surface. Because is is NOT an acrylic it can be removed completely without damaging the negative.
So, call your favorite camera store right now and see if they have any Kodak "Opaque Red" on a shelf somewhere; it is a great product!!!
-- Per Volquartz (firstname.lastname@example.org), May 09, 2002.
Opaque Red is gone, but Kodak still offers something equivalent [and better, I think]. Its Crocein Scarlet. In the past, it came as a liquid [like opaque red], but now it comes in powdered form - you mix it up yourself, as dark as you want. It forms a red dye that does the same thing as Opaque Red.
You can always do it the old way, with lead pencils and retouching fluid. The Kodak product I REALLY miss right now is Film Cleaner. Must have been banned by the EPA.
-- Alec (email@example.com), May 09, 2002.
Herwig- I lived 20 yrs. in Las Veags, so imagine the dust I had to contend with. But, I found this: If you're using a developer with a relatively large amount of sodium carbonate,( D-76 type developers), the dust is more likely pinholes. When the carbonate goes into the acid stop bath, carbon dioxide is formed as tiny bubbles in the emulsion. They gotta go somewhere, so they pop out, leaving tiny holes. Just like dust spots. Try a different developer or dilute your stop to 1/2 of the published formula. Mine is 40ml of 28% acetic to a liter of water. I don't have that problem nearly at all now. Hope this helps.
-- Gary Meader (firstname.lastname@example.org), May 09, 2002.
Kodak continued making Opaque Black after the red variety was discontinued. I believe it was listed as a graphic arts product, and may still be available. I got mine about a year ago and figure the one little bottle should last my lifetime.
-- Henry Friedman (email@example.com), May 09, 2002.
More about spotting negs. with opaque red or black:
DO NOT buy the inferior spotting brushes from your photo store. 99% of these stores have no clue as to what makes a good brush. Instead go to a large art supply store and purchase a Windsor & Newton, series 7, size 00, water color brush. These brushes are the very best brushes made in the world today for applying water color paint. Check the brush for a perfect point when you buy it. If it does not form a perfect point look at the next one - and the next - until you find a perfect brush.
When you use opaque red or black or any other water based pigment, thin these pigments with just enough water so the are opaque, but not thick. After spotting negs - or prints with this brush, wash it in lukewarm water, letting the water flow along the hair. Do not bend the hair. After washing out all pigment shake the brush lightly, and twirl it on your tongue for a few seconds - until it forms a perfect point again. The best to dry artists's brushes is to hang them pointing downward. This prevents moisture from getting into the ferrule and rotting the kolinsky sable hair...
These brushes cost around $10 each, but you will have them for a very long time if you treat them well...
-- per Volquartz (firstname.lastname@example.org), May 09, 2002.
thank you all for your information. to gary meader: i use pyro pmk developer and i do not use acid stop bath, just water. the negs look very fine, but sometimes there are not only pinholes or spots but there is definitively dust on them. rgds herwig prammer
-- Herwig Prammer (email@example.com), May 10, 2002.
If you live near a good graphic arts or printing supply company, or know a printer, there are (or at least used to be :( )spotting aids for cleaning up litho films for platemaking, including sharpie marker type pens that put out a transparent dk red ink. The dark red usually blocks light in normal printing - a quick test on a piece of clear plastic would confirm the effect.
-- Paul Coppin (firstname.lastname@example.org), May 10, 2002.