Little white spots on negative film/scans

Discussion in 'Film and Processing' started by gwendolyn_white, Oct 21, 2006.

  1. I've been developing my own 120 black and white film for a while now and the only problem I can see is that when I scan them into my computer with my film scanner, there are always these little white dots and "scratches" on my pictures. I cannot see them with my naked eye on my film (I've help them up to the light repeatedly trying to find them) but whenever I scan, there they are. I am not doing anything wrong or particular when developing so I'm really curious as to what is causing them. The only thing I can think of is that dust is popping up somewhere along the line, but I really have no idea how. I try to be incredibly careful but they're always there. I also thought it might be because of my camera being dusty but I blew out just about every spec of dust in my camera and lens so that shouldn't be the cause of so many little dots. To be more specific, I'm attaching a picture of what a part of my scanned film looks like. Is there anything I can do to prevent these from appearing? They're not horrible but they're really, really annoying. I find it unusual that they also only seem to appear in big open spaces on my film -- i.e. skies. Thank you for any recommendations or help.
    00IWJU-33086584.jpg
     
  2. If it was dust on the film while in the camera and during exposure, the spots would be darker, not lighter since the dust would blok light from hitting that part of the film. This is rarely the case with roll film, but it happens often enough with sheet film. What you seem to have here is an accumulation of crud on the negative durning or after processing. Can't say for sure if this dust had been picked up while the film was still wet or had settled there after it had dried. Could be a bit of both. Sure enough though, it's often really difficult to see these specks with the naked eye. They do show up under a relatively strong magnifier with the light striking the film at a low angle. If the dust settled on the film while wet, chances aren't good that you'll be able to get it off the film without damage. Wet emulsion is a bit sticky and once dry will hold onto the dust specks like dried adhesive. If the dust settled after the film was dry, you should be able to brush or blow if off. How to prevent it? Make sure your water is clean and filtered and that the drying space is as dust free as possible. No hanging film to dry in dusty basements or in or near rooms with carpeting on the floor. Use the bathroom. Damp mop the floor. Dust all surfaces. Runt the hot water for a few minutes to steam up the room and let it cool down. Then hang your film to dry.
     
  3. Ok, that's what I thought. I do hang my film to dry and dust can settle on it since I do not
    have a 100% developing environment, but I've been trying to keep everything as dust free as
    possible and I guess the room I hang them to dry in is still dusty! I'll try cleaning them to see
    if it makes a difference.

    Thank you for the advice. :)
     
  4. This is dust, and dust is a fact of life. It has to be pretty gross to get on film as it's drying. Try brushing with an anti-static brush under a bright cross light (e.g., an halogen desk lamp) then blowing with canned air.

    If it sticks, then you have a processing problem. Use a final rinse in distilled water and Photoflo. Then squeegee the film (rubber blades not sponges). Wet the squeegee in the Photoflow solution first and shake off the excess. The film will dry in 1/3rd the time and be dry enough at the onset that dust won't stick (unless you drop the film on the floor).
     
  5. I can recollect one film strip where each frame seemed dustier than the previous. This was Tri-X, where is ICE was not possible. I ended up spending 2 Photoshop sessions on one frame that was really bad, maybe 5 hours in total. Looking at the film strip itself, I couldn't see any of the dust.
     
  6. Looks like there are a fair amount of fibers and lint along with general dust. To keep an area dust free recommend the following:

    a. Remove or cover or bag textiles (they generate clothing fibers)

    b. Clean all horizontal surfaces with a tightly woven dampened wipe (microfiber optical cleaning cloth would work well -- cotton or paper will shed fibers) or non-shedding sponge daily when you are doing developing work (do not use cotton wipes as these will shed lots of fibers). Hint: rubbing alcohol will evaporate more quickly than water and will also remove finger prints and other oily residues as well (just be careful not to get it on surfaces or materials that are dyed, have printing or writing inks, that have have adhesives or on surfaces that have lubricants as it may attack or remove these. Clean from top of room to the floor.

    c. Install a HEPA filter air cleaner in the work area. Do not put it on the floor as it will stir up dirt on the floor. Ideally put it above the clean work area so that filtered air bathes your negatives as they dry. You can often redirect the flow by using clean foil or plastic polyethyene bagging but be careful not to restrict the flow of air (keep bagging size larger than opening in unit) as this may cause unit to overheat.

    d. To test how effective your efforts are you can do this: put out a cleaned sheet of aluminum foil. To verify that it is clean: turn off lights and inspect with a bright (preferrably white LED) flashlight at a grazing incidence angle (shine light horizontally across the surface and position yourself so that you can view the surface edge on -- don't get bright LED light in your eyes). If your sheet is clean you should see no particles. If you see particles you need to reclean the sheet. Then leave the sheet out for approximately the length of time that you expose your wet film to the environment. Then re-inspect it. If it there are few particles -- you are done. If not, start looking for other sources of particles. If the particles are long and skinny that means that they are from fibers. If the particles are all about the same color and round and small look around the room for something that could have produced them (foam ceiling tiles, paint with rough or powdery surfaces, corroded metals, etc).

    Other possible sources of particles:

    a. Air ducts for heating and cooling systems. Buy a furnace or vacuum hepa filter material and tape seal it over the opening of the duct. Do not cut the filter material unless you tape seal the cut edges. This will filter the air coming through that duct.

    b. Clothing -- avoid wearing clothes made from plush or fuzzy materials when developing. Wear clothes made from tightly woven fabrics

    c. Materials in the room that have rough surfaces in close proximity to the work area -- for instance, painted cinder block walls, powdery painted walls, or rusted oxidized metals. Cover areas or repaint with a low outgassing (low VOC) epoxy paint (make sure room is well ventilated)or glossy polyurethane paint. Remove all optics or while paint is curing as the paint will often leave a depostion of volatile materials on surfaces.

    c. If you cannot refinish or remove particle sources, bag them with clean polyethylene bagging (white kitchen trash bags work well as you can see the dirt)

    d. Install an air ionizer near the area where you dry the film -- this will de-ionize dust particles and reduce electrostatic attraction to the film. (Ever notice how your TV set (regular not LED) has more dust on it then other surfaces -- it's because the glass is charged up by the ion guns that generate the picture.

    e. Keep pets out of the area

    f. If your skin is dry and flaking, use moisturizers (ones without silicones (di-methicone) on hands and/or wear gloves or long sleeved clothing. Wear a head scarf or hair net if you happen to have especially bad dandruff.
     
  7. PS -- make sure that you clean your equipment -- especially containers for baths and cover them (clean aluminum foil or food grade polyethylene (saran wrap) would work) or put them into clean air tight bins (food grade high-density polythyelene (triangularrecycling code on bottom says HDPE) or polypropylene (recycle code is PP) when they are not being used.
     
  8. The problem may also be in the area where you scan or store your film if they are different from the area where you process it. When you store your film negatives be sure to use clean, non-shedding and non-reactive materials -- no paper products or cardboard. Archival photo storage media are the best. Clean low outgassing, food grade, microwave safe, plastic bins will also work.
     
  9. Everybody's giving good advice about drying the film dust free. Also, what about the scanner. Especially if some of the specs seem to be in the same place on different photo scans - check the scanner glass for scratches, and other dirt. I had to take my scanner apart to clean the backside of the glass. The dirt can be cleaned, perhaps with alcohol, but the scratches are another matter.
     
  10. The image you posted is pretty bad but not unusual. It is a fact of life that dust specks will show up on film scans.

    It is a rare event, in the dusty Idaho agriculture areas I happen to live, that I don't find white spots on my scanned images.

    After scanning, I just put the images through photoshop for touch up and time spent fixing these problems. Sometimes, there is much work to do. If the scan comes out very "speckly", I just try to clean the slide or negative with a bulb type air blower (Don't use compressed air) then re scan it.

    Keep a dust cover over you scanner when not in use and keep good house keeping practices as mentioned above.

    If I can scan film in rural Idaho, it can be done anywhere.

    Dave
     
  11. Use fresh photo-flo as a final rinse, hang up film and wipe it down with pre-wetted in
    photo-flo photo sponges or squeegee, dry in closed closet, or film drying cabinet, sleeve
    in plastic sleeves as soon as film is dry.

    There will always be "some" dust in scans, because the scanner seems to act lika a
    condenser enlarger, exaggerating dust. You just have to resign yourself to the fact that
    you are going to have to do some "spotting" in photoshop. The good side, is that with
    digitizing your images, and spotting in Photoshop, you only have to do it once, and then
    all your prints from this file will be perfect. In wet prints, each print would have to be
    spotted. I always scan at the maximum resolution of my scanner (4000 dpi) because I
    want to scan once, and be done. I do all my spotting on the full-resolution scan. If I need
    a smaller file, I resize and save a smaller one from the retouched file, in addition to the
    full-res scan.

    McCluney Photo
     
  12. Thank you all so much for your replies. I've already done many of the things listed and
    noticed a great reduction in the amount of dust -- basically I made sure to dry my negatives
    in a more "clean/dust free" environment, I wiped down my scanner, and did little things like
    that and the amount of dust was reduced by half, at least.

    So thank you all again for your suggestions.
     
  13. Best thing I ever did, was to start using purified water during development. (I use a purifier can that can hold half a gallon of water, ment to remove and deionise water for drinking in regular households, it uses a carbon filter to purify the water). After i did that, the speck problem was reduced to mere typically 10 minutes of odd spotting jobs on a negative scan.

    I dry my negatives in the shower room after running the water for approx 5 minutes, hot water that create steam and then wait for the steam to dissapare before hanging up my negatives. I put them in plastic sleeves as soon as the film is dry, only taking them out when I am to scan any of them.
     
  14. Don't think of the following as heresy but I have been plagued with these white dots too. Having read these articles, I took some Kodak Tech Pan Film and simply put it on a sheet of white paper and gave it a thorough rubbing with the corner of my shirt! - I turned the film over and did the same... The improvement was dramatic. What small amount of white dots remained on the film was largely (but not completely) removed by Photoshop, using "Dust removal" and "Smart sharpen". Using a camel hair brush etc just didn't work. A point to think about is that when scanning at - say - 4000 dpi, the information extracted from the film is likely to be greater than could (realistically) be extracted by an enlarger. - No matter how good the enlarger is. I suspect that scanning at very high resolution is merely showing the small defects that were always there but would otherwise have gone unnoticed.
     

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