Tiny scratches on film-base. Use hardener?

Discussion in 'Black and White' started by test1, Jun 8, 2004.

  1. Hi all,

    I've noticed that most of my home processed b&w films will get tiny
    scratches rather sooner than later. They are only on the base side,
    never on the emulsion and visible only under 50x magnification
    (enlarger set to produce 13x18cm and looking through 10x focusing-aid
    magnifier) or/and looking along film base in reflected light. This
    happens apparently after first-second printing session, even if I
    place negative in glassless carrier extremely careful without single
    move (and they're in the middle of the frame mostly), or scanning
    (though I seldom scan b&w negs so can't be so sure). I suspect the
    source of problem are tiny pieces of dust, hair (not a big) or
    whatever is found in the air. Usually I use soft brush and compressed
    air to remove any spec of dust that I find on the film.

    On the other hand, I noticed that none of my slide films (I don't
    mount them and keep them in the same sleaves as negatives) don't have
    this problem, neither do C-41 negatives (color and b&w). Is film base
    of slides and C-41 negatives more robust than of silver films?

    Have you experienced same problem? How did you resolve it?

    I'm thinking about starting to use sodium thiosulfate fixer with
    hardener for films (now I'm using Ilford Rapid Fixer). Will it help?
     
  2. A hardener won't help. It protects the emulsion side during processing. Once the film is dry, the effect is no longer present.

    Do you shoot store-bought film or bulk-loaded film? How carefully do you handle your film during processing (or do you have someone process it for you)? How carefully do you handle your film when you print it?
     
  3. I shoot store-bought film, mostly FP4, and I process it myself. The only weak moment in my processing I can see is loading film to the spiral - I don't unspool it at once but rather push it out of the casette little by little. I'm not sure I ever seen a scratch on just-processed film. During the printing I would open the negative carrier, place the frame I want as precisely as possible, close the carrier and insert it carefully to the enlarger (Durst 805), few times I might need to adjust a corner or a side of the negative in the carrier, then I lift top part of the carrier before moving the film. When I need to repeat another frame I will repeat procedure from the very beginng, i.e. I don't pull negative through the carrier.

    Most likely scratches introduced during dragging dust by brush or by force of compressed air. But then what can I do about it?
     
  4. I've just realized that probably when I'm printing one frame I'm damaging another adjacent frame(s). That's frustrating. The frame plates of the carrier appear to be very smooth, just can't imagine what else to do.
     
  5. Which direction do the scratches run? The length of the film or across the width? Are they scratches or cracks? My friend just developed 17 rolls of 120 HP5+. On one roll odd scratches which resembled cracks could be seen on the base side. The cracks ran across the width of the film base, not the length.
     
  6. I too recently noticed tiny scratches on the film base and found the Print File negative page to be the source. The leading edge of each strip seemed to have most of the scratches after sliding the negatives into the page.

    I did a test with an old negative leader, dragging it lightly across the plastic page. When examined closely I could see the same very small scratches on the film base.

    I have since moved to using sleaves from Light Impressions so the negatives are no longer pushed across the plastic when inserting into the page.
     
  7. I agree with Steven. I recently found Print File sleeves to be the source of scratches on my b&w 35 mm negatives. The scratches were always on the base, never on the emulsion. They ran lengthwise on the negative strip, could appear like camera scratches for a few frames (i.e., perfectly parallel to the edge) then fade out, or curve slightly before fading out. Most commonly they were not parallel to the edge. They were intermittent. I might get some rolls with no scratches after scanning, and then one with intermittent scratches on a few frames, and then one with a scratch or two on almost every frame.

    It was very frustrating. My scratches could be seen with a loop while viewing next to a reflection off the base side of the negative strip. They are difficult to find at first, but once you get the hang of seeing them they are easy to spot. Look at your negatives carefully right after drying before inserting into Print File sleeves. Then look at them after inserting once or twice. You can use the ends of the roll.

    I don't know if your scratches have the same source as mine, but I thought I would describe mine in detail since not much about it comes up in a search of the archives.
     
  8. List every point in the chain where something contacts the base side of the film. Start inspecting and checking 'em off. Negative carriers can be smoothed by lightly wet sanding with 800 grit or finer carburundum paper, followed by fine steel wool or Scotchbrite. I never use plastic sleeves. They tend to attract against the film, and any dust then scratches it. Though they're not a perfect solution, I prefer old fashioned glassine envelopes. B&H sells packs of 100 quite reasonably (Savage) and you can get them for just about any size film. The only caveat is never to get them wet- they stick to the negs and destroy them. If that happens, soak to remove, then rewash. Be sure your compressed air is clean and filtered, if you're not using "canned air". Wash your brush with soap, rinse in distilled water, and dry. If it isn't something that can be washed, get another one. Finally, get some Edwals No-Scratch. It will make even deep base scratches completely disappear. Then it's just a matter of cleaning it up!
     
  9. Foldlock (Polypropylene) negative sleeves from Light
    Impressions work for me. (With FoldLock you do not slide
    negative into sleeve which can cause scratchs)
     
  10. I would also avoid pulling the film out of the cassette as you've described to transfer the film to the developing reel. There's a risk of scratches against the light seal on the cassette lips.

    I always pry off the cap from one end or another of the cassette and gently drop the spooled film into my hand. From there I cut off the leader and, handling the spooled film as carefully as possible in my right palm, transfer it onto the loading reel in my left hand.

    It may very well be, however, that one brand of negative sleeves is better than another. When I get home I'll inspect my negatives for the type of scratches you've described. So far I haven't detected anything that's visible in print.
     
  11. Yesterday I've made a test with unused part of developed film. First put it in the negative sleev that I use (Hama transparent paper sleeves) and moved back and forth - no scratches. Then I put the strip into the negative carrier and moved it back and force extremely severe (much more than it would be eventually moved during printing) back and force. I've got exactly same pattern of scratches as what I was concerned about.

    I've checked surface of the pressure plates of the carrier and they appear very smooth except few tiny scratches. Now I'm thinking about finding a way to safely attach pieces of same paper as used in my negative sleeves to inner sides of the negative carrier, but need to find a way that will not involve applying glue to the plates (so if I mess up at least I'd still have original plates). Had anyone done this?
     
  12. Is the negative carrier painted metal, bare aluminum, or something else. Whatever it is, you can certainly smooth it. Not sure why you'd want to stick something on it, but a piece of clear wide shipping tape might work. You can also paint it and wet sand it. My Omega carriers are painted and don't scratch. My Beseler carriers are anodized aluminum and don't scratch much ;-)
     
  13. I also had noticed the damage (scratching and micro-denting) of the
    negative by my enlarger's negative carrier for some time but since
    subsequent prints on the same (diffuser) enlarger did not show the
    imperfections (at least up to 8x10 prints), I had grudgingly accepted
    the price (for making prints !) Last week though, after some
    difficulty in getting a satisfactory print from a negative wide wide
    exposure range, I decided to scan and do the dodging and burning in
    photoshop. The 4000dpi scanner is nowhere as forgiving as the
    diffuser enlarger was and at this point, it seems to me that once the
    negative was placed in the enlarger, it would be tough to scan without
    spending lots of clean-up time in photoshop.

    My negative carrier is a practically new Saunder 35mm (anodized
    aluminum, kept clean and scratch free) and I have not tried covering
    the film contact surfaces with the sleeves but I am wondering if there
    is a device, similar to the (Nikon Coolscan) FH-3 film-strip holder
    that can hold the negative by the sides, without touching image area
    and to use that to slide each frame into position in the enlarger ?

    BTW, if I remember it correctly, the first enlarger I used many years
    ago, had raised rails on the negative carrier to grab the edges of
    the negative. This was essential since the rest of the surface was not
    as smooth as the brushed aluminum as the new negative carriers but the
    principal is the same. Anything that comes in contact with the
    negative (with as much pressure as negative carriers) would leave a permanent impression.
     
  14. I have Durst Bimaneg negative carrier with painted metal inserts, bought along with this Durst 805 enlarger second hand. Would be happy to hear if some other owners of this enlarger can see minor scratches or "bites" on their negatives.

    Conrad, my idea to put paper is to eliminate contact of the soft negative with much harder metal. You say your carriers 'almost don't scratch', which actually means they do scratch a little. Most of the time this isn't noticible on 5x7 prints, though few frames of my last film were damaged enough to require now scanning&retouching. But on 9x12" prints (from 35mm negs) careful examination most of the time will show some white holes. This is my major concern after I've got negatives worth printing in quantities and perhaps several times.

    Sassan, your comments relieved me as now I see it isn't only me with such problem. Sad that this problem exists.

    I'll try make photo of a damaged negative if I could capture it right.
     

Share This Page