Why am I getting these weird stripes?

[gcoates]

I'm shooting using a Nikon F5 and bulk-loaded film in plastic canisters. I'm getting some weird stripes on each roll of film lately. I'm attaching a couple of sample images, and I'm hoping someone might be able to give me an idea of what's causing the stripes.


An image that has the stripes (I'm talking about the 2 dark lines near the center of the image)


Detail of the stripes

 

[Andy K]

If the stripes are all the way along the roll, then it could be dust in the dust traps of either the bulk loader or the film cassette scratching the film.

 

[fotch]

I would guess there is dirt on the felt of either the bulk loader (if it has felt, some don't) or in the cassette. You could try a factory roll to see if it disappears or if remains, then look at the camera.

 

[Saganich]

This looks like it is caused by uneven pressure on the film or dirt but not enough to scratch. This can happen anywhere the film makes contact with something else. If same on multiple rolls - camera or bulk loader. Variable from roll to roll - film cans.

 

[flash26c]

I just got 2 rolls of 120 TriX back from the lab that had these same stripes. Since I was using an SL66, don't think it was caused by the camera and I've never seen them before. I blamed the lab and of course they said it must have been in the emulsion.

 

[srs5694]

You might want to try running a roll or two of store-bought (non-bulk) film through the camera as a diagnostic. If the stripes persist with that film, then you can be pretty sure that the problem is in your camera; if not, and if they reappear with the next roll of bulk film you shoot, then you can be pretty sure the problem is in the bulk loader or conceivably the bulk film you're using.

 

[Blighty]

Do you squeegee your film after processing? I've had similar looking marks on my negs when I used to use one. Quick advice is - don't use a squeegee......ever!

 

[John Koehrer]

Is the same lab processing both films? If it is I'd think about changing labs or DIY.