Light leaks, I think, disappear as the roll moves along?

[horacekenneth]

So I'm seeing some very slight black edges on the top and bottom of my 35mm negatives, so slight it's all on the right side of the sprocket holes (i.e. away from the picture, not causing visible problems yet). It's about two fingernails long and occurs between photos for the first ten photos, after that there's no marks at all.

I'm thinking it's a light leak but two things are strange to me, the fact that it happens equally on the top and bottom of the negative and the fact that they go away about a quarter of the way into the roll. What could be causing that?

 

[mweintraub]

They could be going away because you're not in enough light anymore for the harsh light to penetrate the camera back.

 

[horacekenneth]

They could be going away because you're not in enough light anymore for the harsh light to penetrate the camera back.

I don't think so, first, I'm shooting in a variety of light throughout the whole roll and second this has happened on four or five rolls now and it's always consistent about where the leaking starts and ends.

 

[StephenT]

Replace all the light seals, on both ends of the door and in the grooves top and bottom on the body.

I use self adhesive felt on the doors and wool knitting thread in the grooves. Works great.

 

[Sirius Glass]

Replace all the light seals.

 

[MattKing]

Are they bulk loads or are they factory loads?

Are you using one of the films that is susceptible to light piping?

 

[horacekenneth]

I am using Arista.edu 400, not bulk loading.

I do plan on replacing the light seals, I'll get a kit from Jon Goodman, but it's just strange to me that it stops after the first ten frames and is mirrored perfectly above and below, makes me wonder if it's something else.

 

[MattKing]

One final question:

Are you, by chance, using one of those cameras like the Canon Rebel 2000 that first winds the film to the end and then winds it back into the cassette, one at a time.

 

[Ken Nadvornick]

For roll film a repeating light leak on only the first few frames can sometimes indicate a single leak that has penetrated directly through the first few layers, but is eventually attenuated by those non-transparent layers themselves. In such a case the pattern repeats, but becomes more faint as the roll is unwound relatively quickly.

Realistically this is more often the case with 220 roll film which lacks a backing paper, and not 35mm film protected by its cassette. (Unless your answer to Matt's Rebel question is yes. Or you roll your own and your cassette has a leak.)

Is any of the geometry of your camera/cassette/film system such that the above may in any way be a contributing factor?

Ken

 

[horacekenneth]

Matt, no, I'm using a Nikon F2.

Ken, I think I understand what you're saying but I'm having a hard time picturing how it would happen to the first 12 inches of exposures inside the camera. (I'm not rolling my own) The pattern would make more sense to me if it was all one light leak that penetrates through the first couple layers of wound film. The only place that the first section of film is outer (to the rest of the film) is when it is inside the cassette. But what are the chances of having 4 or 5 rolls (in a row) from freestyle that all have the same leak?

I'll try and get a photo up of the light leaks later.

 

[adelorenzo]

Is it possible that this is caused be development? The beginning of the roll is on the inside of the reel maybe you are getting surges in there?