Scratch in Film Base

[rguinter]

Greetings everyone: I have an Infrared B&W image that somehow got a single scratch about an inch long across the film base. i.e., it is not on the emulsion side. The scratch is very prominent on a flatbed scan and the scratch reduction software I have doesn't seem to help. Does anyone know if drum scanning or wet-mount scanning will eliminate the scratch in the scan? I sense that it will due to the matching of refractive index of the film base with the mounting solution. But I was wondering if anyone has tried this. Comments would be welcome. Many thanks. Bob G.

[IanMazursky]

Fluid mounting will certainly help. It really depends on how deep the scratch is.
I have drum scanned some really (someone walked over it then sent it to me) scratched negs and i was surprised how much Kami fills in.
In general, base scratches mostly go away, emulsion scratches are another story. Depending on how many layers the scratch goes through, it can be a big cleanup job.

A little retouching may still be needed on a deep base scratch, but thats usually an easy fix.

[Bill_1856]

Rub a little oil off the outside of your nose with a finger, and rub it in to the scratch -- it should become invisible. (Same index of refraction.)

[Nathan Potter]

As Bill says, although I'm not sure about nose oil. But the best you can do is use an index matched fluid to fill in the scratch. I'd take a worthless negative, put a similar scratch in it, and run some tests.

Nate Potter, Austin TX.

[rguinter]

Thanks for the comments. Interesting thought about nose oil though. I've never checked the R.I. of mine. Anyone know what is the material of Rollei Infrared film-base? Among other things I'm a polarized-light microscopist and I have quite a few R.I. liquids on hand. One might match pretty close. But I suspect the bromonaphthaline in most Cargille R.I. liquids could cause damage. Just a thought. Bob

[Jim Michael]

I've used this stuff in the past with great results along with a cold light head - http://www.freestylephoto.biz/541512...o-Scratch-1-oz.

[joeyrsmith]

Or--
Last chance try.
Depending on artistic value. Drum scan #1 Flatbed #2
Fix it with software then have a digital neg made.

[Bill_1856]

I must be showing my age -- every darkroom worker of my generation knows about the nose-oil trick.
The Edwal No-Scratch works quite well also, as does plain old Vasoline, but is messy.

[Don Hutton]

Greetings everyone: I have an Infrared B&W image that somehow got a single scratch about an inch long across the film base. i.e., it is not on the emulsion side. The scratch is very prominent on a flatbed scan and the scratch reduction software I have doesn't seem to help. Does anyone know if drum scanning or wet-mount scanning will eliminate the scratch in the scan? I sense that it will due to the matching of refractive index of the film base with the mounting solution. But I was wondering if anyone has tried this. Comments would be welcome. Many thanks. Bob G.

In my experience, it's one of the really significant advantages of drum scanners - base scratches almost always disappear completely. I scan a lot of 35mm film with a dedicated film scanner and there are almost always a few visible base scratches (even putting the negs carefully into sleeves produces base scratches which are visible under high magnification - to minimize this I actually cut the film and scan it straight from the drying cabinet). The light source of the scanner has a big effect - the more diffuse, the less visible.

FWIW, they are very easy to remove with the healing brush tool and a bit of practice.

[rguinter]

Many thanks for the comments everyone. Since I've never worked in a darkroom before the nose-oil comment was of interest. My guess is its R.I. would be somewhere around 1.50. So I may try a couple of liquids I have here that I know won't damage the film base. The image is a nice Rollei IR of a good site locally but not something I would want to spend too much money on to fix. I'm quite sure the oil trick will work and I will give it a try when I finish with the rest of my dry scans. For someday when I get around to drum scanning some of my best I'll keep in mind that it really does a nice job fixing up scratches. Cheers. Bob G.