ped Posted May 7, 2011 Share #1 Posted May 7, 2011 Advertisement (gone after registration) Guys This has happened a few times now, on different types of film. Normally noticeable in lower light where I'm using a slower speed. See the line on the left?? It is always at the top of the negative (in landscape orientation) Any ideas what this could be? Something up with the speeds? Camera is an M4P. Cheers ped Link to post Share on other sites More sharing options...
Advertisement Posted May 7, 2011 Posted May 7, 2011 Hi ped, Take a look here Underexposed line on negatives. I'm sure you'll find what you were looking for!
sfage Posted May 7, 2011 Share #2 Posted May 7, 2011 that's gotta be some sort of weird scanning issue. Link to post Share on other sites More sharing options...
ped Posted May 7, 2011 Author Share #3 Posted May 7, 2011 Afraid not, it's on the neg. Link to post Share on other sites More sharing options...
adan Posted May 8, 2011 Share #4 Posted May 8, 2011 Could be one of two things (possibly more, but these are the two I know about) 1) Something sticking out off the edge of one of the shutter curtains, effectively narrowing the gap that determines "shutter speed" in a localized area, causing underexposure in that area - the dark band. However, that would usually be more obvious at HIGH shutter speeds (narrower gap to begin with, thus more effect for a give amount of obstructive object.) 2) It could be a light leak that is producing a smooth gradient of fog inward from the edge along that side (which happens to be disguised a bit since that is also the side from which the actual window light is coming). The lack of blacks in the tripod-mounted camera in the image, left, looks like possible fog. The source of the leak being a failed felt light trap along the shutter - they do fail in the M4-2/P, they were replaced by longer-lived plastic strips in the M6 et seq. One of my M4-2s showed exactly this kind of leak. The dark area is where the shutter channel itself protects the film from the leak - it is counterintuitive that the leak shows up away from the image edge, so I'm supplying a schematic, not-to-scale diagram. green = film red = shutter curtain(s) black = channel where shutter slides blue = felt light trap - worn away in the bottom section, functioning in the top section yellow = light Note that the fogging does not begin right at the edge of the frame, due to the angle the light has to make to leak around the shutter - thus the dark (i.e. correctly exposed and unfogged area) closest to the frame edge. Note also that if this is the case, the leak occurs not during the actual exposure, but simply over time as the film sits behind the not-perfectly-light-tight shutter, between pictures. The beginning or end of a series, depending whether your habit is to advance the film after each exposure, or just before each exposure. The amount of the effect also depends on a lot of other things, such as whether the camera was in really bright light during the fogging period, or in a bag/case, or uncovered but in dim light. And how long the break between pictures was (leaks are cumulative). So it can tend to look random unless one remembers all the details of the camera's "life" while any particular frame was sitting behind the shutter. 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! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/151204-underexposed-line-on-negatives/?do=findComment&comment=1666491'>More sharing options...
250swb Posted May 8, 2011 Share #5 Posted May 8, 2011 Afraid not, it's on the neg. The negative, or all the negs on a roll? If it seems random and appears every now and again I would suspect a light leak, perhaps by changing the lens in very bright light or leaving the lens off the camera for long periods with a film still in it. Probably the felt light trap as Andy says. Steve Link to post Share on other sites More sharing options...
pop Posted May 8, 2011 Share #6 Posted May 8, 2011 As Andy says. In addition, the dark band could conceivably be caused by development issues. Link to post Share on other sites More sharing options...
otto.f Posted May 8, 2011 Share #7 Posted May 8, 2011 Advertisement (gone after registration) What intrigues me is the sharpness of the border of the line, this speaks for me against light leak and even more against development problems (I suppose agitation occurs in every development). What speaks against light leak also is that the line is darker and not lighter. It occurs not always and mostly with slow shutter speeds, so it seems a shutter problem, as though the first or the last part (depending how you held the camera in this image) of the journey of the shutter is going faster. Link to post Share on other sites More sharing options...
Broadside Posted May 8, 2011 Share #8 Posted May 8, 2011 Is it possible that the level of developer in the dev tank didn't cover the entire spiral, only coming up to the level of the line so that the darker segment only had developer during agitation? Just a thought. Link to post Share on other sites More sharing options...
ped Posted May 8, 2011 Author Share #9 Posted May 8, 2011 Thanks a lot for the kind replies. I have had a test to see if there is any mileage in the development problem theory. I'm using a patterson tank, which suggests 290ml of liquid with one 35mm roll. I just poured in 300ml (as I normally do) and it JUST covers the spiral. I wonder if during agitation the spiral moved along the central columb and therefore lifted the spiral out of the dev liquid for a short time? I just shot a test roll at all speeds and souped it, the negs are drying now. This time I used 400ml and loaded the negs upside down into the spiral, so hopefully if there is banding I can see if the banding moves to the other side or if it's always at the top of the shot, which should confirm/dispel adan's very gratefully received ideas. I can't see any marks on the negs I just shot, so when they are dry I'll scan them and check up close. Hopefully it's as simple as a dev issue. Some guys on Rangefinderforum said they had similar lines because of this, or because of dirty reels. Watch this space! Cheers ped Link to post Share on other sites More sharing options...
otto.f Posted May 8, 2011 Share #10 Posted May 8, 2011 If it turns out to be a development problem, I wonder how you used to agitate Link to post Share on other sites More sharing options...
ped Posted May 8, 2011 Author Share #11 Posted May 8, 2011 Every min for 10 seconds. I only have one spiral in the tank and think it might slip up the center column so when the dev settles it's not covering the whole spiral. My test roll (which I just shot and showed no evidence of problem) were souped in 400ml to make sure. I've ordered a second spiral to keep them firmly in place and will use 400ml from now on to make sure. As I use stock concentration anyway it doesn't waste anything. Cheers ped Link to post Share on other sites More sharing options...
otto.f Posted May 8, 2011 Share #12 Posted May 8, 2011 Every min for 10 seconds. I only have one spiral in the tank and think it might slip up the center column so when the dev settles it's not covering the whole spiral. My test roll (which I just shot and showed no evidence of problem) were souped in 400ml to make sure. I've ordered a second spiral to keep them firmly in place and will use 400ml from now on to make sure. As I use stock concentration anyway it doesn't waste anything. Cheers ped Yes but I mean do you rotate or do you turn the tank upside down Link to post Share on other sites More sharing options...
ped Posted May 8, 2011 Author Share #13 Posted May 8, 2011 Both, rotate, flip, rotate, flip etc. Link to post Share on other sites More sharing options...
otto.f Posted May 8, 2011 Share #14 Posted May 8, 2011 In that case I don't understand the straight line, if it would be a development problem Link to post Share on other sites More sharing options...
ped Posted May 8, 2011 Author Share #15 Posted May 8, 2011 I was just saying on Rangefinderforum it's things like this that make me want to pack it all in, sometimes. Nothing's ever simple, is it! Angry of Oxford Link to post Share on other sites More sharing options...
otto.f Posted May 8, 2011 Share #16 Posted May 8, 2011 That's because producing images is still a miracle, either way, analog or digital, let alone capturing the decisive moment Link to post Share on other sites More sharing options...
ped Posted May 8, 2011 Author Share #17 Posted May 8, 2011 Well said. Perhaps I value my film shots more highly because they are more work to produce. I'm going to shoot a roll this week and remove the lens, use different speeds etc and develop in a tank with two spirals and 400ml and report back. Wish me luck and thanks to everyone for the help. ped Link to post Share on other sites More sharing options...
otto.f Posted May 8, 2011 Share #18 Posted May 8, 2011 Somehow though, for me, film photography shows the effort of the maker, it seems to have more soul I wish you insight. Link to post Share on other sites More sharing options...
lincoln_m Posted May 9, 2011 Share #19 Posted May 9, 2011 Is there movement in the back pressure plate of your M4? I'm thinking a light leak for most of the image except the top part near the hinge. Could it be a rectangular lens hood that is for a narrower angle than the one used? Like a 35mm hood on a 28mm lens? When you say slow shutter speeds do you mean the clockwork ones, 1/30th and slower? Regards, Lincoln Link to post Share on other sites More sharing options...
ped Posted May 9, 2011 Author Share #20 Posted May 9, 2011 Hi mate I think it's the dev issue, as I shot two rolls with no probs when I used 400ml of liquid. The hood is a square one for the 21mm lens, and i saw it with the 28mm lens also with designed hood. So at the moment my theory was not enough dev and the tank was resting between agitation in my slightly sloped sink. I simulated with an empty reel and saw the top of one section of the reel wasn't covered. To solve it I'll use 400ml and have also ordered a second reel to put above the bottom one to stop any movement of main reel when in development. Here is a picture from my test roll - had some drying mark issues but no lines: Cheerio for now and thanks a lot for all the helpful advice, I must say I'm really encouraged by the support out there for us film photographers. Really nice to know I can ask questions and have lots of experts help me out, so thanks for taking the time to post, all of you. ped Link to post Share on other sites More sharing options...
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