Vertical Stripes Aligning with Sprocket Holes

Good luck.

Maybe a clue, or maybe just a red herring, but the closest match to this I have found so far is the following, taken with a different camera on Velvia 100 (expired) and processed commercially:



This frame was also underexposed, a bit worse than the b&w above. The vertical bars aligned with the sprocket hole pattern are clearly here, especially in the blue channel, although I do not see them on the upper margin. A separate mystery, or part of the puzzle?

Well, one mystery is solved - namely, why the film is so thin.

On the black and white film, are the bars visible when you hold it up to the light? Is it possible that the light from the scanner in the sprocket holes piped across the film as it was scanned? What kind of film was it?

Snowfire said:

Maybe a clue, or maybe just a red herring, but the closest match to this I have found so far is the following, taken with a different camera on Velvia 100 (expired) and processed commercially:

View attachment 289230

This frame was also underexposed, a bit worse than the b&w above. The vertical bars aligned with the sprocket hole pattern are clearly here, especially in the blue channel, although I do not see them on the upper margin. A separate mystery, or part of the puzzle?

Click to expand...

This one looks like it's vertical banding + there are two horizontal lines going through frame too.

It's def something to do with mechanics of camera as there are lots of examples of this banding online.

Snowfire said:

Maybe a clue, or maybe just a red herring, but the closest match to this I have found so far is the following, taken with a different camera on Velvia 100 (expired) and processed commercially:

View attachment 289230

This frame was also underexposed, a bit worse than the b&w above. The vertical bars aligned with the sprocket hole pattern are clearly here, especially in the blue channel, although I do not see them on the upper margin. A separate mystery, or part of the puzzle?

Click to expand...

Could the vertical bars that are aligned with the sprocket holes (commercial processed film) be from light leaks from the sprocket holes in the scanning?

The two horizontal lines on the color image are, I believe, due to foreign matter on the lens. A problem, yes, but not relevant to the issue at hand.

The bands in the b&w negative are faintly visible to the naked eye in the one frame. The scanner is somewhat more sensitive in bringing them out, but they are not scanning artifacts. Other frames on the same roll do not show the issue as clearly. The ones in the color image are most distinctly in the blue channel, whereas the scanner lamp is white--and I have scanned numerous other 35mm frames with this scanner that did not show this.

The full-width vertical bands at the left of the color image are not aligned with the sprocket holes, and I presume them to be panning speed artifacts (swing-lens camera.)