Leica LTM LTM Leica slow speed dial position

[Richard G]

I have a IIIA, I shoot it without the leather case. I find myself accidentaly turning the slow speed knob to 8 when doing photowalks. I only noticed it after 2 to 4 frames of shooting. Then the some of the photos shot at 1/1000 has capping (darker on the right side). I have repaired this camera, replaced the curtains. Not sure if the capping is a result of the 1/8 position of the slow speed knob while using 1/1000sec, or maybe im still missing something after replacing the curtain. It is imposible to see the action of the curtain with slow speed installed since the shell should be installed as well. I thoroughly examine the sound of 1/1000sec with 1/8sec actitaved and i can hear a difference.

Sorry: I missed this before my post. Interesting.

 

[picture_man124]

Sorry: I missed this before my post. Interesting.

I tried shooting 1/1000 without lens and 1/4 activated while looking at the shutter action. It realy drags the 2nd curtain. This is before adjusting the slow seed knob.

 

[qqphotos]

The other reason I didn't see mentioned (but may have missed) is that if you're using B and and have the slow speed dial set to, say, 1 sec, there will be an additional 1 second delay after releasing the button before the shutter closes.

 

[Dralowid]

The other reason I didn't see mentioned (but may have missed) is that if you're using B and and have the slow speed dial set to, say, 1 sec, there will be an additional 1 second delay after releasing the button before the shutter closes.

Yes, we covered this a while back

Well, this has been bugging me so I had a go at it on a III, a IIIa and a IIIa syn.

If you set the camera to B (or Z) on the fast speed dial and the slow speed dial is not at its fastest speed then when you depress the shutter button the shutter opens but when you release the shutter button the slow speed mechanism will run for whatever exposure time it is set to before the shutter closes.

So, if you were doing a long exposure on B you might find yourself with an additional one second if the slow speed dial was set on one second.

This only happens when the fast speed dial is set to B (or Z) and does not apply to any other of the settings on the fast speed dial.

 

[picture_man124]

Update on my previous comment about shutter capping:

For context, I am an experienced repairman. I have the replaced the curtain of my IIA and cleaned everything including the first curtains spring roller.

I disassembled the camera again. Then, I reassembled the slow speed knob and this time I nailed the 1/8 and 1/4 sec measurement using Audacity. Before, I measured the 1sec to be in the range of 900ms to 1200ms, this means the slow speed post is deeper. With the new adjustment, 1sec is actually about 700ms, but 1/4 and 1.8 is spot on, I guess the slow speed sensor has already deteriorated overtime and it cant push the slow speed post deeper to get 1sec spot on measurement. But 700+ millisecond is still within the (+-)1/3 of a stop tolerance for 1sec.

I had a controlled test shot using Ilford HP5. I tried shooting 1/1000 in various setting including 1/8 and 1/4 activated in the slow speed dial.

This time, I did not see any shutter capping at 1/1000.

I therefore conclude that the incorrect adjustment of the slow speed knob will affect the high speed resulting in an unwanted shutter capping. So after the correct adjustment, even if I accidentally turn the slow speed dial while using 1/1000 it wont affect the photos.

I have a IIIA, I shoot it without the leather case. I find myself accidentaly turning the slow speed knob to 8 when doing photowalks. I only noticed it after 2 to 4 frames of shooting. Then the some of the photos shot at 1/1000 has capping (darker on the right side). I have repaired this camera, replaced the curtains. Not sure if the capping is a result of the 1/8 position of the slow speed knob while using 1/1000sec, or maybe im still missing something after replacing the curtain. It is imposible to see the action of the curtain with slow speed installed since the shell should be installed as well. I thoroughly examine the sound of 1/1000sec with 1/8sec actitaved and i can hear a difference.