blakley Posted March 12, 2006 Share Posted March 12, 2006 I took my iiif with me to Rome last week & took a couple of rolls. Some were outdoors in the daytime (not that common an environment for me) and I was using 400 speed film, so I had occasion to use 1/500 for the first time, and I got some bad results. The attached picture shows the problem. This happened on four or five frames, but not on other frames on the same roll, and never on two consecutive frames. It happened on both horizontal and vertical shots. No sprocket holes are damaged in any way. No defect of any kind appears on the film rebate or in any of the inter-frame spaces. Some shots at 1/500 do not display the problem. My speculation is that this is a shutter-tensioning problem and I should simply avoid 1/500 (this camera recently had the curtains replaced) - but I am also wondering if it's possible I simply dragged a knuckle on the wind knob while shooting. Opinions?<div></div> Link to comment Share on other sites More sharing options...
blakley Posted March 12, 2006 Author Share Posted March 12, 2006 PS - camera was oriented so that top is the edge close to the take-up spool: probably an important point. The scene is the top of the Spanish steps, for trivia buffs. Link to comment Share on other sites More sharing options...
david j.lee Posted March 12, 2006 Share Posted March 12, 2006 Bob, did you hear about the print swap at the street photography forum? dave Link to comment Share on other sites More sharing options...
blakley Posted March 12, 2006 Author Share Posted March 12, 2006 I didn't - it's probably a bad time for me workload-wise anyway, but thanks for the heads-up! Link to comment Share on other sites More sharing options...
ronald_moravec1 Posted March 12, 2006 Share Posted March 12, 2006 Send it back. The new curtains are defective. The curtains have holes so small you can`t see them. but when combined with the actual exposure you get streaks. I just went thru this. The camera went to Mark Hama and he fixed the problem with new curtains. Since you already paid, guess you have to go back to the first person. I can take a pretty good guess who. Expose the second curtain to the sun and don`t take a pic. Expose the first on a second frame and do not take a pic. No lens on the camera. Continue on doing pics. Until it gets worse, you will most likely be ok if you avoid 1/1000 and 1/500. Link to comment Share on other sites More sharing options...
john_shriver Posted March 12, 2006 Share Posted March 12, 2006 I'm sorry, but I see no signs of holes here. This is absolutely classic shutter fading on a screwmount Leica. (I know, I've worked on the same problems on my bottom-load Leica and Canon cameras.) The uneveness is because when the slot gets really thin, the roughness of the weave the fabric gets to be a significant percentage of the slot width. You may also see some diffraction events, unsharpness where the slit is really narrow. The question is whether the shutter curtain replacement also included a complete CLA, cleaning out all the bearings, and replacing with the right modern synthetic lubricants. Replacing the shutter without doing that is futile. Link to comment Share on other sites More sharing options...
john_shriver Posted March 12, 2006 Share Posted March 12, 2006 Oh, fading means uneven exposure due to the curtain width changing too much as the curtains travel across the focal plane. It should narrow some, as they speed up as they go. But not too much, and not too little. It can come from incorrect take-up spring tensions. It can also come from incorrect positioning of the curtains on the drum. Link to comment Share on other sites More sharing options...
blakley Posted March 12, 2006 Author Share Posted March 12, 2006 The curtains were actually replaced because the old ones had holes. I agree that the symptom here has nothing to do with holes. I'm not sure if everything was overhauled - but if I can get around this by using slower film outdoors I'm happy to live with it for now. Link to comment Share on other sites More sharing options...
al_kaplan1 Posted March 12, 2006 Share Posted March 12, 2006 Holes would make dark streaks on the negatives which would appear light on the print, but they usually show up more as spots because most of the time the shutter isn't moving. Link to comment Share on other sites More sharing options...
david j.lee Posted March 12, 2006 Share Posted March 12, 2006 you did such a great job with the leica forum swap that i though you might like being there and not organizing it, just swaping. dave Link to comment Share on other sites More sharing options...
blakley Posted March 13, 2006 Author Share Posted March 13, 2006 I'd already discounted the possibility of holes, both for the reason you mention, Al, and because I'd already had that problem fixed... It's sort of interesting to me that you can have a "dark leak" like this in addition to the more interesting "light leaks". I think I'll run off the last few frames of the current roll at high speeds just to check where the danger zone is... Link to comment Share on other sites More sharing options...
adrian bastin Posted March 13, 2006 Share Posted March 13, 2006 Before sending this back to the repair shop that installed the curtains I would make absolutely sure that they know what they are about, because it doesn't look like they do, or have taken a short-cut. The slow speeds should be overhauled if they have not been; sometimes tension is increased on the curtain that drives the slow speeds in order to get them working but that results in just what is happenning to your pictures, at high shutter speeds. Link to comment Share on other sites More sharing options...
adrian bastin Posted March 13, 2006 Share Posted March 13, 2006 The only reason I know something about the problem is that I've bought several Leicas which have been tensioned up to look like they are working right; the latest, an M2, I took some tension off the second curtain and it is working ok now, but will have a CLA soon, anyway. Link to comment Share on other sites More sharing options...
ulrich_messmer Posted March 13, 2006 Share Posted March 13, 2006 I have a IIIf with exactly the same problem after it got brand new shutter curtains put in by Leica/Solms. It only happens at speeds faster than 1/25oth and has nothing to do with development. The shutter speed theory is the only one so far that matches my test results, because at the faster speeds I also get underexposed frames. The mechanical Leicas seem to get this problem quite often. Link to comment Share on other sites More sharing options...
tom5 Posted March 13, 2006 Share Posted March 13, 2006 I had a similar problem with a If. I sent the camera to John Maddox, who said that the weave of the fabric on the edge of one of the shutter curtains was causing the problem. As I remember, he replaced one of the curtains, that was worn badly in any case and adjusted the shutter, with complete success. Camera works perfectly now. Link to comment Share on other sites More sharing options...
kirk_teetzel Posted March 13, 2006 Share Posted March 13, 2006 I had the EXACT same problem with mine. The curtain that is in front of the film when the photo has been taken was lagging (2nd curtain?) I ended up having a huge chunk of film in there that was causing this. It was prettty easy to fix. Link to comment Share on other sites More sharing options...
alex_lofquist Posted March 13, 2006 Share Posted March 13, 2006 Typical of a IIIC or IIIf black dial. You have a sluggish leading curtain that isn't opening as fast as it should. As you say, this could also happen if your finger is touching the shutter knob during exposure. Link to comment Share on other sites More sharing options...
Gus Lazzari Posted November 1, 2007 Share Posted November 1, 2007 Folks, The First and Second curtains have barrel springs that after proper cleaning and re-lubricating, must be adjusted so the curtain travel times across the film opening are at 18 to 20 milliseconds. This is the proper spec for these LTM curtains. The slow speeds are then adjusted, finished off by the high-speed slit width adjustments. You need a shutter speed checker that has multiple sensors so it can time the edge-to-edge speed. Whoever did the repair did an amateur job of it; this is after all, camera repair 101... Gus Link to comment Share on other sites More sharing options...
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