Dust spots

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I'm having a lot of trouble with spots on my home printed B&W negatives. I brush them before printing with a blower brush and rinse them in a wetting agent before drying in a quiet place, Any tips ?

I'm going to upgrade my enlarger (condenser type) soon. Are other types of enlargers less prone to dust spotting ?

-- Dusty Negative (top@end.com), January 09, 2001

Answers

Dusty,

Try to give your lamphouse, condensor spheres, and negative carrier area a good cleaning. (Windex is fine, except for the lens). Blow out the internal bellows area with canned air. About 1/2 hour before printing, mist you darkroom down with plain water with an ordinary atomizer. This will help settle dust. Finally, continue to brush down negatives before insertion in the negarive carrier. All of this should help with dust spots. Best of luck!

Joe Wasko

-- joseph wasko (jwasko@erols.com), January 09, 2001.


Whoops, forgot to add something. If you place a plastic trash bag over your enlarger when not it use, you can avoid a lot of dust build up.

-- Joseph Wasko (jwasko@erols.com), January 09, 2001.

I use nothing more than a "Hurricane Blower" or large ear syringe from the drugstore. Canned air is fine too. If your enlarger will let you view the neg by raising the lamphouse, do that, or hold it under the lens. Blow off any dust particles until it's clean. Anything you see is going to print, so be fussy. The underside of the neg tends to stay clean once blown off. I don't have real proof, but believe it helps to have the enlarger electrically grounded. Unless something is dried into the neg, it should be quite easy to make spot free 8x10s. BTW, I have a dog, the darkroom is in the laundry room, and I heat with wood, and it still isn't a big problem. Misting is a good idea and you should keep a humidity gage around and run a humidifier if necessary to keep the RH above 40%. Condenser enlargers tend to show dust a bit more, but going to something else isn't necessarily an "upgrade". You can make a fine print with almost any enlarger design. Condenser, diffusion, and cold light each have their own quirks to contend with.

-- Conrad Hoffman (choffman@rpa.net), January 09, 2001.

I use LOTS of canned air and an anti-static brush. I give a blast to the condensers & the lens before each printing session. I dust my negs as follows. 1) I give several gentle swipes with the antistatic brush front and back. 2) A blast of air front and back.3) after placing neg in carrier I hold the neg in the carrier up to the light and give both sides a blast. BTW I use the type of canned air that has a swivel nozzle so the can is always held upright.You dont want to have propeellant get on the negs or glass surfaces so always hold the can in a vertical position and never shake the can as you spray. I don't have a dry humidity problem in my darkroom. (My home has a humidification system built into the Heating/Cooling system). BTW a diffusion system will supress dust but it is by no means a panacea. Good Luck, R

-- Robert Orofino (rorofino@iopener.net), January 10, 2001.

Go to a medical supply house & purchase something like a Honeywell HEPA air filter. The type used for allergy sufferers. Run it in your darkroom for 20-30 minutes before printing and a lot of your dust problems will disappear. Couple it with washing down the walls & floors with a damp rag & you will cut down on the dust you stir up moving around. My darkroom is in a basement with exposed lath & plaster around the heating vents. At times I have had pieces if it drop into the chemistry. Since getting the heavy duty air filter dust spotting has dropped dramatically. That and basic cleaning with wet rags or mops have made a big difference. Using a brook is a loser as all it does is push the dust into the air to land on your negatives. If you add a darkroom air filtering system for the air coming in, the air evacuation system over the darkroom trays should take out much of the airborne dust & lint as you print. (as well as the chemical odor)

-- Dan Smith (shooter@brigham.net), January 10, 2001.


I am sort of a "clean" fanatic in my darkroom and fortunately it has paid off. During the past three years I have owned three enlargers. The first two were condenser type but my current one is an Omega D5 with an Aristo VC cold lite head. Since purchasing the cold lite head dust has become a "non-issue." It would be my suggestion to reconsider your plan to purchase a condenser head enlarger. My cold lite head is a real pleasure to use. I have given consideration to a HEPA system in my darkroom not only to reduce dust but to remove chemical particles from the air. One of your respondents suggested the HEPA which confirms that my thought process is in the right direction. I also place a garbage bag over the enlarger when not in use. Good luck beating the dust.

-- Bob Bedwell (rlb@triad.rr.com), January 11, 2001.

Realise that a HEPA filter only deals with particles, not with any chemical vapors or gases.

Many of the units do have a charcoal filter, but under any chemical load their lifespan is measured in hours, certainly less than a week. And the charcoal absorbs chemicals out of the air even when the unit is off.

-- Terry Carraway (TCarraway@compuserve.com), January 11, 2001.


Years ago I read an article in one of the photo mags that told of a man who blew up balloons, thumb-tacked them to the walls of his dark-room, and when he was going to print he would rub them with a rayon cloth. Seems this creates static electricity and it attracted the dust. Of course he cleaned the enlarger, pallet and darkroom before beginning. Dave

-- H. David Huffman (craptalk@lvcm.com), April 14, 2001.

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