Removing spots on negatives.

[waynecrider]

Is there any procedure to remove dark spots on the negative before having to spot the print? I'm working on 4x5 negs. What causes this? Thanks

 

[waynecrider]

Maybe I should explain this a little more. It appears as tho there is a deposit on the negative having looked with a 8x loupe. If it was dust on the negative when the neg was exposed it would be a white spot. Since it is a dark spot I am attributing it to the possibility of dust during the drying process and adhering itself to the wet emulsion. Can anyone confirm. Because I contact print Ziatypes the revelation was not so apparent as in my enlarged silver print.

 

[Monophoto]

Dust on film when it is exposed causes light spots on negatives that print as dark spots. This can best be dealt with by cleaning holders before loading, storing loaded holders in in dust-free areas (some people use zip-loc bags), and dusting off the holders before inserting them in the camera.

You can carefully spot those negative defects so that they produce light spots on prints, and then spot the prints as a final correction. Marshall's spotting dyes applied with a very fine brush (5-0 or finer) on the back (non-emulsion) side of the print will work. Or you might try a colored dye - Dr. Martin's transparent watercolor works well. Colored dyes have the advantage of being less binary than spotting dyes and you can gradually darken the light spot. A magenta dye is easy to see on the back of the negative, and if you are print on variable-contrast silver paper, it increases localized contrast which helps mask the flaw.

Dust on negatives as they are drying tends to cause white spots on prints. Using a wetting agent (eg, Photoflo) in distilled water as a final rinse, and then drying in a dustfree area would be a good start. Practicing your print spotting skills is also helpful.

And most importantly, recognize that one of the immutable laws of photography is that perfectly composed and exposed negatives always attract more dust.

 

[Toffle]

I'm interested where this discussion will go. I shot a roll of HP5 120 last month that seems to have a dark line/lines across at least half the frames. Curiously, it is completely absent in others. I have never experienced this before or since with this camera. (GS-1) Apart from the mystery of how the lines got there, I am wondering how to work with these negatives. I could scan and fix in PS, but I would really like to wet-print these.

Any suggestions?

Cheers,

 

[waynecrider]

I'm interested where this discussion will go. I shot a roll of HP5 120 last month that seems to have a dark line/lines across at least half the frames. Curiously, it is completely absent in others. I have never experienced this before or since with this camera. (GS-1) Apart from the mystery of how the lines got there, I am wondering how to work with these negatives. I could scan and fix in PS, but I would really like to wet-print these.

Any suggestions?

Cheers,

That's weird. If it was caused by the mirror you'd loose part of the frame, but it would account for the occasional problem. Was it a one roll thing? If it was I'd attribute it to the film.

 

[Toffle]

That's weird. If it was caused by the mirror you'd loose part of the frame, but it would account for the occasional problem. Was it a one roll thing? If it was I'd attribute it to the film.

Well, according to my Catholic upbringing, I my first instinct is to blame myself. :rolleyes: If it was a hair (of which I have precious little) that accidentally got trapped when I switched films, I would end up with a light streak across the frame. This is a very definite black line across the negative frame. (it fades in and out on some frames) I can't imagine any way this could happen in the camera. My guess that either I really messed something up in processing the film (I am capable of some of the most incredible hack-jobs) or that there was a defect with the film. Again, my background leads me to blaming myself, so maybe I bought it on the wrong day of the week, or something.

Still, I'm stuck with a roll of negatives from a fairly important shoot that are virtually unusable in my wet darkroom. I'll have to scan a print so you can see what I'm talking about. (not today, though... I'm out the door for a nine-hour rehearsal... gotta rescue Dorothy from the Wicked Witch)

Cheers,