Hasselblad film magazine and line on edge of film

[GraemeMitchell]

I've been noticing, occasionally, a thin line of decreased density that runs just along side the film edge (about an 1.8 of an inch into the frame) down the length of my 120 film. It runs down both sides of the film, perfectly.

For some time I thought it had something to do w/ a reel, how I was loading film onto the reels, or something in the processing stage, but when I mentioned them to a old and long time hassy shooter he said he'd had similar line them years ago and recalled they had something to do w/ the film magazines. I checked into my film, and indeed, it's not something I've ever experienced on cameras other than the hasselblad.

I'll attach a crop w/ increased contrast (it's the dark vertical line, not that loose hair in there).

Would appreciate any thoughts or experiences or fixes or etc.

 

[mike c]

Could also be in the film,a little while back there was mention of a 120 film that had a rough paper backing that caused some similar to this.What make film are you using and does it happen with all brands of film? Also try cleaning and blowing out the mag. and insert real good.

 

[epig]

I have a mag that does the same about a millimeter or two from the edge. Under a strong loupe, I looked at the neg and noticed the line was wavy and repeated its pattern regularly, so I am assuming it's the roller on the shell scratching it somehow.

Since I have other mags, I just wrote "scratches" on a piece of tape and taped it across the darkslide and put it at the bottom of my case so it doesn't get used.

It's pretty close to the edge, so I may crop it out when printing those good negs I got before discovering it!

Eric

 

[Q.G.]

That could indeed be it.
Tiny burrs on the small rollers in the shell above and below the film gate leaving marks in the emulsion.
If so, there should be a pattern that repeats itself every 6 mm or so.

No need to decommission the back because of burrs on the rollers though. Just polish them away (and then, if necessary, put some black paint over the polished bit, and smooth that too).

If no repeating pattern, it's something else. I can't think of anything in the back that would then be responsible.

 

[epig]

<snip>

No need to decommission the back because of burrs on the rollers though. Just polish them away (and then, if necessary, put some black paint over the polished bit, and smooth that too).

<snip>QUOTE]

So . . . clean it up with a bastard cut file and Sharpie out the scratch marks, eh?



Eric

 

[Andrew K]

check that the serial numbers on your back and film insert match - if you have a mis-matched pair that could be the problem

Also are you agitating enough - could be a density build up on the edges in processing. Does it happen on color films that youhave commercially processed?

 

[GraemeMitchell]

Thanks for the input. I'll look to see if there is anything obvious on the rollers.

I do have mismatching backs and inserts. My hassy stuff has been hobbled together 2nd hand and back seals, upkeep, maintenance has always a weak link in the V system, ime.

I rarely shoot color film through it, maybe 1 roll of color to every few hundred black and white, and I have 6 backs I use, so while I haven't noticed it in the few rolls I've shot, that doesn't mean anything.

I do have one stiff back. Not smooth. The hardest to advance and to wind in and out. Not that that means it would do this, but that's the first one I'll look at, as it's probably being rougher on the film.

 

[mikebarger]

Add (with a small file) a notch to one of the backs next to the two notches that are already there; then you can tell which back the film went through.

Mike