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gmed
26-Nov-2017, 21:49
I occasionally get a line on the film on the end of the side that corresponds to the film holder feeding latch. The film holders are in pretty new condition, no leaks. It is also 0.5" into the photo so I dont think its the holder, I dont get anything on color films. Also, this never occurs when I use the BTZS tubes. I have a feeling this has to do with the Jobo tank, which I only load 4 at a time, leaving one bland in the middle. I use a roller, but the side of the lid ends up being lifted a little as it is uneven.
the line is perfectly linear, as you can see on the image. I can also see a faint line on the film itself. Not sure where this is coming from.

any idea would be greatly appreciated as this results in a big crop which Im trying to avoid
172333

Sandro
27-Nov-2017, 00:00
It seems to me this has to do with light or development, probably the first.
Are there any not-black area inside the camera.

gmed
27-Nov-2017, 01:32
It seems to me this has to do with light or development, probably the first.
Are there any not-black area inside the camera.

it doesnt happen all the time. only with BW, which i develop at home. not very consistent. I mainly saw it on the last batch

Doremus Scudder
27-Nov-2017, 05:42
You may be getting some internal reflections from the edge of the filmholder flap. Try sanding it with very fine sandpaper to take the sheen off and see if that helps. Ive done this with most of my holders.

Best,

Doremus

devb
28-Nov-2017, 11:18
When I had that happen a few years ago, I found pinhole light leaks in the tape that acts as the flap hinge. I replaced the tape with black gaffer tape (the real stuff that costs $20 a roll) and it hasn't recurred since.

gmed
28-Nov-2017, 14:03
Just from the placement of the line relative to the tape, not sure how this could be due to a light leakage. It's not near the tape and it's a straight line

Doremus Scudder
29-Nov-2017, 07:57
When I had that happen a few years ago, I found pinhole light leaks in the tape that acts as the flap hinge. I replaced the tape with black gaffer tape (the real stuff that costs $20 a roll) and it hasn't recurred since.

The loading flaps only need the tape hinge to hold them on the holder; when the flap is closed, there should be no light leaks whether there is tape there or not. The flap itself should block all light.

Doremus

nbagno
29-Nov-2017, 08:06
I get the same exact line on some of my negatives and in the same location. Trying to limit the number of holders to see if I can narrow it down.


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stawastawa
29-Nov-2017, 18:10
something to do with how your film sits in the film holders for developing? something to do with the agitation method?

nbagno
29-Nov-2017, 20:08
something to do with how your film sits in the film holders for developing? something to do with the agitation method?

Iím using a jobo expert drum, canít see how it could create a line like this.


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gmed
29-Nov-2017, 22:50
If yours happens on the expert, then its not the form the Jobo, as I use the regular Jobo, Then it must be from the holder, thats if yours is also exact same location.

gmed
29-Nov-2017, 22:52
the only thing I can think of is that this line lines up with the notches where the film is loaded.

172440

gmed
30-Nov-2017, 22:59
The loading flaps only need the tape hinge to hold them on the holder; when the flap is closed, there should be no light leaks whether there is tape there or not. The flap itself should block all light.

Doremus

You are exactly right. its the only logical explanation. The line is on the film, both BW and transparencies, which means its not my Jobo. The V groove absorbs light from the shiny film, and bounces it back at 45 degrees onto he film again. I have to now sand them. what grit sand paper did you use?

again, thank you

Doremus Scudder
1-Dec-2017, 01:12
You are exactly right. its the only logical explanation. The line is on the film, both BW and transparencies, which means its not my Jobo. The V groove absorbs light from the shiny film, and bounces it back at 45 degrees onto he film again. I have to now sand them. what grit sand paper did you use? again, thank you

I just used a bit of 380 grit wet/dry sandpaper I had lying around. The object is to just knock the sheen off the beveled edges of the filmholder.
It's not very invasive; give it a try and see if it solves your problem (low-hanging fruit and all that). I think what happens is that non-image-forming light gets reflected from the beveled edge of the holder onto the film making a line of denser exposure. It is somewhat subject-related and if there is a very bright area at the right place in the image, the line can be quite pronounced.

Best,

Doremus

John Layton
1-Dec-2017, 05:08
I actually have a homemade printing easel that had the same problem. I had painted the printing frame's inside edges with a "flat" black which was not flat enough...and my solution was to reduce the thickness of these edges down to almost nothing. But Doremus...what a great idea!