War against dust

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Help me print without dust on the negative. It seems i can't win :(

-- Emilio Conesa (ecmaj7@aol.com), October 13, 1999

Answers

Many friendly people answered this question in this thread:

http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=000SuT

-- Peter Olsson (peter.olsson@lulebo.se), October 13, 1999.


No, you can't win. That's why you spot. Get a #00000 (5 zeros) spotting brush and a set of Spotone dyes.

http://www.ravenvision.com/rvapeter.htm

-- Peter Hughes (leonine@redshift.com), October 13, 1999.


The more you clean, the more dust you'll find on your negatives. Just leave your enlarger in place and clean it once or twice a year. Besides, it has got to do with the atmosphere too, humidity for instance.

-- Lot (lotw@wxs.nl), October 13, 1999.

Just made a great discovery several days ago, use Pledge Grab-it's or Swiffer's anti-static cloths, works great! Pat

-- pat j. krentz (krentz@cci-29palms.com), October 13, 1999.

I found air to be the best cleaning agent, because it is free of unwanted side effects. Any kind of mechanical cleaning involving rubbing with a cloth or a brush is prone to a few drawbacks:

1) scratches (which are harder to spot on the print than dust), 2) deposition of unwanted stuff (either films of some agent or grease in the cloth or brush or particles/hairs), and 3) creation electrostatic charges making de-dusting almost impossible.

The best thing I found so far is a rubber ball just fitting my hand, with a nozzle (sorry, can't remember the English term right now). The small rubber balls are mostly unsuitable to generate sufficient flow. When I compress this really hard, the resulting air stream is sufficient to blow away any dust except maybe in very few negatives where a particle really sticks to the film surface. In that case, I use a clean handkerchief to remove the speck very gently. Then I use my "compressor" again to blow away the cotton left by the hanky. Instead of my rubber ball, compressed air in cans might do the trick, too, but I haven't tested it, because the rubber ball works fine and costs much less. (About as much as one can of air.)

If your eyes are keen enough, visually inspect your negative under grazing light incidence. (The wording may seem a bit stuffy, but I am not a native speaker.) What I mean is this: Switch room lights off, enlarger on, hold negative plane parallel to enlarger's optical axis and parallel to your line of sight. Look along the surface of the negative in a direction perpendicular to the optical axis. You will then see even fine particles, because they are brightly lit and contrast well with the dark background. (The effect is the same as that of dancing dust particles in a sun ray shining into an otherwise dark room through a window.)

-- Thomas Wollstein (thomas_wollstein@web.de), October 14, 1999.



The rubber ball sounds like a good idea, but I know that compressed air only adds static, with the Pledge cloth's you don't have to use pressure, just pass the film gently over the cloth or vis versa. Pat

-- pat j. krentz (krentz@cci-29palms.com), October 14, 1999.

Pat

I have never observed static with compressed air, and I wonder how it could add some. Could you elaborate?

-- Thomas Wollstein (thomas_wollstein@web.de), October 15, 1999.


Thomas,

The air actually creates static by moving past the surface.

Why not use a StaticMaster or Kinematics anti static brush systems? StaticMaster uses a low level radiation emitter to neutralize static and the soft brush removes the dust. The other system seems to use conductive fibers in the brush to do a similar job.

There is also a product out called a Tacky Roll Cleaner. This is a roller that you pass the film over and it gently sticks to the dust and lifts it off the film.

You could also use a ZeroStat gun. These used to be very common for vinyl records. It works by generating a large static charge that charges everything. Since like charges repel, the duct is repelled from the surface.

Many ways of doing things.

-- Terry Carraway (TCarraway@compuserve.com), October 15, 1999.


"many ways of doing things"...... yup, but you still won't win. Have you ever tried one of those Kinematics style brushes? pssst, c'mere(whispering) they don't work. I have a staticmaster brush too but I don't think it works better than my "straight" camel hair. I use a combination of compressed air, breath(i have particularly dry breath) fingertips, brushes, cussing and inspection as Thomas described. Good luck Emilio....but you won't win.

-- trib (linhof6@hotmail.com), October 27, 1999.

Hi Emilio,

what I'm doing about this subject is to clean the air with an air cleaner 1 1/2 hours before I start printing to get out the dust particles of the air in the darkroom. Compared with the time before there is a significant progress. To get off the dust of the negative I use compressed air out of the tin.

Paul

-- Paul Mueller (Paul.G.Mueller@t-online.de), October 30, 1999.



1) Make sure that the darkroom has positive air pressure rather than negative air pressure. In other words, filtered air should be *blown* into the darkroom rather than *drawn* in with the normal exhaust fan. Always keep the door shut unless in use. 2) Vacuum regularly with a HEPA type vacuum, e.g., a Miele. This is the only type that doesn't exhaust dust while it works. 3) After vacuuming, wipe down horizontal surfaces, including the floor, with the new type "cloths" which have a molecular attraction for dust. One brand is "Swiffer." 4) Before enlarging do the normal negative cleaning. I use an anti-stat brush device which does both sides of the negartive at once. Or use air or the tacky roller. 5) Last, in the dark, turn on the enlarger lamp and check for dust on both sides of the negative by holding the negative in its carrier under the enlarger's light, tilting it around at a steep oblique angle. Any dust will be visible and can be dealt with. njb

-- Nacio Brown (njb@limn.net), October 30, 1999.

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