Marks on neg, what did I do wrong?

[dealy663]

Hi,

 

I processed my 4th roll of film at home a couple of days ago and got

some strange marks on the negative. I was wondering if any of you

might recognize what I did wrong that would have caused them. These

marks appeared on 3 or 4 frames in the middle of the roll. I loaded

this roll of 120 Tri-X on to a plastic Jobo 1510 (I think) reel and

processed it by hand in a Jobo plastic tank. I don't remember doing

anything wrong like mishandling the film as I wound it on to the reel.

 

This is my 3rd roll of 120 using these tools, and the first time I've

seen these kinds of marks. I developed in D-76 for the standard 6:45

min, using normal agitation once every 30 seconds.

 

This first link is to a scan of the whole frame:

<a

href="http://pangloss.grandprixsw.com:8000/photography/pub/April%202005/042305/ProblemWhole.jpg">Whole

Problem</a>

 

This next link is to a 100% crop of the problem area:

 

<a

href="http://pangloss.grandprixsw.com:8000/photography/pub/April%202005/042305/Problem100.jpg">100%

crop</a>

[jack_fisher1]

I am guessing there was a kink allowing adjacent layers to touch. The Jobo plastic reels must be clean and dry before loading. I also slightly cut the corners of the leading edge of the film before loading to prevent snags. My "normal agitation" includes a little twist (or spin) at the end of inversions, then a slight rap on the table. Hope this helps.

 

JF

[chris_waller]

I'm inclined to think these may be abrasion/friction marks. Could the film have scraped against anything as it was being loaded?

[conrad_hoffman]

My first thought was some kind of scuff mark, but the 100% crop picture looks more like something picked up while drying. Could the neg have brushed against anything while it was drying, or might anyone else have been near it? Since the marks on the print are light, the defect on the neg must be dark. Pressure can "expose" film, light leaks, static, or chemical action. If it's not something silver based, than it could be something picked up during processing or drying. Could also be a defect from the factory, but that's extremely rare. Check everything and see if it happens again.

[jerry thirsty]

When you were pulling the wet film off the reel, is it possible it make contact with itself and then you pulled it apart? Wet film sticks like glue and when you pull it apart it can damage the emulsion.

[kaiyen]

I've had film flap around after I pulled it out of the reel and have parts touch each other. It has been sticky but I've never yanked part of the emulsion off.

 

This thread is also at apug, and it's a certifiable mystery, apparently.

 

allan

[dealy663]

I saw the marks as soon as I pulled the film off of the reel. Someone on APUG suggested it might have been the tape at the end getting stuck on the film while I was loading the reel.

 

Sounds plausible to me. Those big marks are definitely not from the squeegee.

 

Derek

[craig_bridge]

Try looking at the negative with magnification and see if there is anything left attached to either side or if the dark marks are in the emulsion. If it is in the silver layer, there may have been hairs, fibers, or another thin light obstruction in the camera body at the time of exposures.