Gouges and Omega Lids

[Kevin Kehler]

I have two questions, one is help diagnosing a problem for which the second is a possible solution. For the past 2 years, I normally develop my film by loading it on Paterson plastic reels in a darkroom bag and then developing in a Paterson tank; however, for the past 2-3 months I have been having a problem with gouges (bigger than scratches) on my film. It normally occurs on the film closest to the center of the reel (i.e. the leader which has been threaded) and does occasionally move farther out to about 3/4 of the way on the film but no further (the last frames loaded on the reel are never touched). If you look at the first two thumbnails attached, you can see where I have highlighted the problem. I use a Paterson 3-reel and 1-reel tank (120 film), it occurs in both tanks and does not matter which reel or which position the reel is in (i.e., bottom reel this time, middle reel next time). I can develop 3-4 batches without a problem and then there is a problem on the next 2 or 3 rolls. I have done a number of thorough cleanings of all equipment, so I don't think it is a contamination issue unless there are minute particles in the chemicals (it doesn't look like it to me but...).

Is it possible that my reels are somehow scratching the film or causing the film to buckle on the interior positions and gouge themselves during agitation? If perhaps there is some form of residue from incomplete dissolution of my developer, could this make these kinds of marks (I use ID-11/Perceptol but due to water quality, the B portion never complete dissolves. I normally try to filter as much residue as possible out prior to using).

Note, that this is not a question of handling after developing since the film already has these marks once I open the tank for washing.

So my possible solution is using stainless steel with an Omega top but does this have to be done in the dark? There doesn't seem to be a way to get chemicals in or out. So is it pour in chemicals in the dark, put lid on, turn lights on, turn lights off to change chemicals? There's got to be an easier way.

 

[MattKing]

Kevin:

First, I would check the darkroom bag for something caught up in it that is scratching the film.

Next, I'd check your Paterson tanks and lids and centre columns to see if there is a sharp edge or protrusion that the film is catching on when you are loading.

Third, I'd look for something similar on the cores of the Paterson reels.

With respect to the Omega lids, is there not a smaller, friction fit cap in the centre of those lids?

EDIT: the center cap should cover the hole where you pour the chemistry in and out of. That hole has a light tight baffle. END EDIT

Matt

 

[Anscojohn]

The Omega lid is light tight, even without the center cap, as far as I know. As for the gouges--you've got me stumped.

 

[ic-racer]

The tip of my scissors makes marks like that very easily.

 

[fschifano]

Unless the film becomes dislodged from the reel during processing, it's not at all likely that the tank, lid, reels, or center core is causing this problem. Do you use a changing bag to load the tank? What else is in the bag that might scratch the film? I'm betting that it's nothing at all to do with the tank.

 

[George Collier]

This looks like 120 film, judging from the scale of your fingers in the scan, and the reels. On the middle scan, it looks like frame #12, indicating that when you remove the film from the paper backing, you load the last exposure of the roll first into the reel. I know from my experience, that the curl on 120 film can be aggressive. Could it be that in removing the film from paper and starting onto the reel that you are scratching it on itself? I haven't had this happen, but I'm always concerned about it as well as kinks.

It also looks like, on the middle scan, that there is also a black defect of some kind just to the left of the largest circle, which would not be a scratch?

 

[Kevin Kehler]

Thanks everyone for the suggestions. I have checked the bag, tanks and reels and cannot find anything that would make such marks; I don't use scissors when loading 120 film since I just peel the paper away. One thing I forgot to mention is that the scratches seem to be on the non-emulsion side which would indicate a gouge in the celluloid.

George, I am also wondering if I am somehow scratching the film on itself; and the mark is something behind the negative (I just held it up to the window to get a shot).

With regards to the Omega lids, I didn't realize how easily chemicals can pour in and out of the smaller gap; question answered.