I need some help in diagnosing problem light areas on some images (examples included).

[Neil Milton]

Advertisement (gone after registration)

Hi.
I recently bought a Leica M6 with a summicron 50mm. I ran 3 rolls of tri-x through the camera so far. I had them developed at a lab in Warsaw and then scanned by the lab. The scans were terrible from the lab so I decided to scan them myself. (apologies for the neg scans below - I scanned them as archive using Silverfast).

On some of the photographs there are strange light areas (dark here) coming up from the bottom of the photograph.

I know that this can be caused by not flattening the negative properly when scanning, however, this is not the problem here - as having looked at the neg itself through a loupe, these areas are on the negative itself.

I have until the end of April with the warranty for the Leica and the lens, so I want to rule out any issues with the camera before then.

Does anyone have any idea what might be causing this? When they happen, they look uniform (more or less).

My main issue troubleshooting is that they only occur on some of the photos. On others, there's no issue at all.

Any thoughts or ideas?

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[jankap]

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Seems to be a normal picture to me.

[Neil Milton]

If you look at the bottom of the image you'll see brighter areas that seem to line up with the sprockets on the film roll.

It's the same on each of the images posted. 

So far (on Reddit) Bromide drag has been suggested, as has light leak / light seal problems. Any other thoughts as to what it might be?

[250swb]

The light is coming in from the top (the image projected inside the camera is upside down and back to front), so the seal around the top of the rear door could be the culprit given the M6 has no other seals around the rear door, or shouldn't have. Unclip the door and look to see if there is a seal that looks like a strip of rubber.

[Neil Milton]

4 minutes ago, 250swb said:

The light is coming in from the top (the image projected inside the camera is upside down and back to front), so the seal around the top of the rear door could be the culprit given the M6 has no other seals around the rear door, or shouldn't have. Unclip the door and look to see if there is a seal that looks like a strip of rubber.

I'll check this at the end of this current roll, however, of 3 rolls, it is only present in the 2nd (chronologically) of the 3 rolls. If the door was missing the rubber, it would be present throughout, I think. Thanks for the suggestion though. I'll check it out.

[250swb]

9 hours ago, Neil Milton said:

I'll check this at the end of this current roll, however, of 3 rolls, it is only present in the 2nd (chronologically) of the 3 rolls. If the door was missing the rubber, it would be present throughout, I think. Thanks for the suggestion though. I'll check it out.

It might depend on how long it is between shots and the intensity of the light. Let's assume you already have some leakage on the current roll, tape up the rear door and finish the roll, if there are no marks from that frame onwards it will confirm or disprove the theory.

[jaapv]

Advertisement (gone after registration)

It could just as well be an error in developing. Insufficient agitation or exhausted chemicals can cause similar marks.

https://www.photo.net/discuss/threads/stripes-on-negative-s.487861/

[giannis]

This is bromide drag. Its characteristic is those stripes of different density emanating from the sprocket holes.

The reason it happens is that bromide, a byproduct of development that inhibits further development, concentrating around the sprocket holes and from there slowly dripping down across the height of the film, leaving a streak of less development across its path, and more development inbetween the sprocket holes. Because bromide production is proportionate to development, the effect is stronger in well exposed areas where more silver is developed (skies for instance or snow etc.).

In any case, the fix is really simple: more agitation. It spreads around the bromide quickly and doesn't let it build up concentration and inhibit development. Most normal agitation schemes, like 10 seconds every minute, are enough to stop bromide drag in the vast majority of film+developer combinations. If you still get it, 5 seconds agitation every 30 seconds are sure to fix the issue once and forall. Some developers are better buffered and less sensitive to bromide drag, but the agitation I described is adequate for any developer.

Usually bromide drag is an issue with very reduced agitation (like a couple inversions every 3-5minutes), or the extreme case of "reduced agitation" which is stand development. It's rare to see in normal dev regimes, with normal agitation and normal (not overly long) development times.

Your camera and lens are absolutely fine. This is purely a development issue and very easy to solve. Talk to your lab, if it wasn't an one-off error they might be just inexperienced and it'll be helpful to pass on the above info about bromide drag. Since B&W dev is done by hand, it could be an honest mistake, like forgetting to agitate if they got distracted by something. Another reason could be using stand development for some reason. Talk to them, ask how they develop, and tell them about bromide drag.

Edited March 2, 2021 by giannis
typos, content

[250swb]

2 hours ago, giannis said:

This is bromide drag. Its characteristic is those stripes of different density emanating from the sprocket holes.

 

It could be, but three films all coincidentally loaded into the tank the same way up? Of course coincidences do occur. But equally the bands could be due to standing in the fixer without agitation. The rule is to rule out one thing at a time but yes bromide drag is an option.

[giannis]

3 minutes ago, 250swb said:

it could be, but three films all coincidentally loaded into the tank the same way up?

I think since they were developed in a lab, we can't know for sure. Also it's not clear if the images presented as all from different rolls or just one (he does say it doesn't show up in all pictures).

I think what makes it more likely, is the fact that we have both skies and snow on the ground (which acts like a sky, in terms of exposure and bromide drag). So even if some films were loaded upside down, you'd still get bromide drag, just in the snow instead of the sky. Also if the bromide drag is severe, it doesn't matter which way is up, since even mid-level exposure is enough to create it, doesn't need to be high exposure like on the sky.

I mean there can be many possible explanations, but it does look awfully lot like bromide drag.

[Neil Milton]

8 hours ago, giannis said:

I think since they were developed in a lab, we can't know for sure. Also it's not clear if the images presented as all from different rolls or just one (he does say it doesn't show up in all pictures).

I think what makes it more likely, is the fact that we have both skies and snow on the ground (which acts like a sky, in terms of exposure and bromide drag). So even if some films were loaded upside down, you'd still get bromide drag, just in the snow instead of the sky. Also if the bromide drag is severe, it doesn't matter which way is up, since even mid-level exposure is enough to create it, doesn't need to be high exposure like on the sky.

I mean there can be many possible explanations, but it does look awfully lot like bromide drag.

Hi - thanks for all the comments. To be clear, the 'issue' is only present on 1 roll of the 3 that were developed. I thought I had specified that but on re-reading my post above I didn't.

It's for that reason that I'm leaning more to bromide drag being the issue - as from comments here and on reddit, it certainly seems like it's a development issue.

Though, a few more rolls through the camera and developed at a different place will help diagnose further I guess.

Apologies for the confusion

[adan]

I won't argue with bromide drag as a strong possibility.

I would just mention that there are two other processing effects that look similar (if in some cases reversed tonally). And also involve the sprocket holes.

And that is too MUCH agitation "pumping" either developer or fixer through the holes and across the film, resulting in localized "streaky" overdevelopment (neg with dark stripes) or overfixing (dissolving part of the silver in the image - neg with light stripes).

It happens if the film is agitated by tilting or inverting the tank back and forth too forcefully, such that gravity is pulling the chemical back and forth through the holes. Or possibly with vertical agitation in deep tanks.

And less likely to occur with Paterson-type or mechanized rotary agitation.

[bags27]

Does bromide drag occur much when it's not stand developing? If the average commercial development is (say) in the 5-8 minute range, how much drag would there be? I honestly don't know; I'm asking.

I very much doubt this is the cause, but are you sure that the back of the camera was tucked into the bottom piece? I have had something similar happen when I close the bottom but the back isn't locked into it.

[giannis]

12 hours ago, adan said:

And that is too MUCH agitation "pumping" either developer or fixer through the holes and across the film, resulting in localized "streaky" overdevelopment

Correct, that's the cousin of bromide drag, often called "surge". Usually it looks a bit different, sometimes you get blocky patches or sharper strips compared to bromide drag.

 

1 hour ago, bags27 said:

Does bromide drag occur much when it's not stand developing? If the average commercial development is (say) in the 5-8 minute range, how much drag would there be?

If development is normal, with a general purpose dev and normal agitation scheme, for a normal time (no pushing), and fresh chemicals, the chances of bromide drag are virtually zero.

But that's a big if, especially since we have no idea of the development scheme used.

[tommonego@gmail.com]

I have seen this with limited agitation and over agitation. especially if it was hand developed in a tank too large for the film reel and another reel wasn't placed in the tank to stop it from pistonning going up and down while agitating.