1

I have a large color photo poster (75x50) printed on true photographic paper (not an ink print or something). While I was glueing it on an MDF board, sadly a drop of my sweat has dripped onto it, and now after drying there is still a noticeable circle where the water had soaked into the paper (which gets sticky when wet, as we all know).

Does anybody know of a smart way to remove that stain (without introducing new stains...) ? Could vapour be a solution (I don't dare trying it unless somebody confirms that it could work)?

Remark: of course the naive way would be to water the whole photo and dry it afterwards, like they already have done in the lab. But I fear that it does not dry up all that regularly, so this is not an option. And, of course, doing all the work again is also not an option.

1

I would suggest that you take some other photographs printed on similar paper, and experiment. Sweat onto them, let it dry, then try different techniques.

A: Put a puddle of distilled water on a stain, swirl with a Qtip for N minutes, then pull the water off initially with a paper towel, and finish with a piece of lens tissue. (The water wicking into the paper towel won't shed onto the print.

B: Same idea, use distilled water mixed 200:1 with photoflo.

C: Start with 1 liter of warm water and 2 drops of uncoloured dish detergent. Swirl, blot, and immediately rinse with B, above. The idea is that detergent will remove residual skin oils.

D: If any of the above worked, try repeating it. If it worked slowly,wet it repeatedly, then dry it by putting down a piece of lens tissue backed up with a paper towel. (A towel by itself will leave towel lint embedded in the gelatine.)

E: is the stain lighter than the print? If so you may be able to use retouching colours to fix it. Get lots of practice first. It's an acquired art.

Examine with a 10 power jewelers loup. You are looking for the following:

  • is there an actual change of colour between inside the ring and outside the ring?

  • is all the discolouration just in the ring itself? (Surface tension favours junk collecting at the point where the liquid meets the solid surface. Coffee stains are rings, not spots.

  • is there a height difference between inside and outside? (The gelatine has swollen and not shrunk back. You may want to use a very low angle illumination to check this. An LED flashlight laying on the table works well.

  • is there stuff stuck to the print?

After working on it, do you still have a stain? Have you moved the stain? If it's a ring stain, not a spot stain, can you move the edge of the stain to an inconspicuous location?

  • I am impressed. Very detailed and scientific strategy. You have encouraged me to look closely at the stain with a dental loupe which I happen to have. It seems that the stain has appeared also because I wiped over it when it had not yet dried up (scratches visible). I could solve this in a remarkably easy way: breathing at the stain for several minutes - the gelatine surface has relaxed and now the stain is almost invisible! – oliver Jan 20 '18 at 19:36
  • Scratches: Try letting it dry, then with clean fingers rub the crease by your nose, then gently rub the scratched area. The nose grease will fill the scratches and make them far less visible. This is a trick used with scratched negatives to get an acceptable print. – Sherwood Botsford Jan 21 '18 at 0:09
  • I tried it and it worked! Thank you so much. It must have been the nose part that made the difference. Now the only problem is, I don't remember my name anymore. Any suggestions? – oliver Jan 24 '18 at 18:10
1

The gelatin emulsion has deformed. Gelatin swells when wet and contracts as it dries. What you have is an unevenness in thickness. Your best approach will be to procure a gloss or matte photo spay lacquer and uniformly apply to the entire print.

Another approach, but dangerous, soak the entire print in water. This will swell the gelatin. Then, using a rubber roller, squeegee the print face down, like a decal to clean plate glass. Allow to dry and perhaps the pressure of the squeegee action will restore the gelatin to a uniform thickness. The danger is, the print might not release when it dries.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.