colyn
ישו משיח
Dear Roger,
In practice however the 1/20th of a second running time over the filmgate is too slow. Remember the running speed is not even, but it increases towards the end.
Please post proof of this claim.
If the shutter curtain tension of both curtains is set properly both curtains will run at the same speed both at the beginning and end of its run.
All this caused serious exposure problems at the high speeds so Leitz choose for a faster running shutter for the later cameras. In fact only the 1/200, 1/100, 1/60, 1/40 and 1/30 speeds are reliable on the Leica I, II, III, IIIa and IIIb.
Erik.
If this were true Leitz would have never released these models for sale. Instead they would have sped up the shutter from the beginning. So again I would ask anybody with proof of these claims to present it..
colyn
ישו משיח
From a users perspective the shutter speed dial drops down properly on later conversions when 1/1000 is selected.
Mine drops down.
Both of my IIIa's sit up slightly when 1/1000th is selected.
Photo of the top plate..

And here is a view of the upgraded shutter brake..

Erik van Straten
Veteran
Please post proof of this claim.
If this were true Leitz would have never released these models for sale. Instead they would have sped up the shutter from the beginning. So again I would ask anybody with proof of these claims to present it..
In the times these cameras were released, these speeds were never used because the films were too slow.
Look, I've been using these cameras for many years and I know were I am talking about.
Just do the shutter test I've told you and you will see that I am right.
Erik.
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Erik van Straten
Veteran
Leica II, Hektor 50mm f/2.5, Tmax400 printed on Ilford MGIV fb.
Erik.
Erik.

Erik van Straten
Veteran
The actual camera used.
Erik.
Erik.

colyn
ישו משיח
In the times these cameras were released, these speeds were never used because the films were too slow.
Then why were they included?
What about 1/20th??
Look, I've been using these cameras for many years and I know were I am talking about.
Just do the shutter test I've told you and you will see that I am right.
Erik.
As have I since 1958.
I've done the shutter test before with good results throughout the range.
If your camera(s) are not working properly maybe they passed through the hands of a hack at one time.
I heard this claim once before and as yet neither this person or you has shown proof of the claim.
Melvin
Flim Forever!
The 1/1000 on the IIIa, IIa, IIasynch or IIIasynch is usually not working right, it is not reliable. You better do not use it. It is almost not possible for even the most experienced repair personnel to make 1/1000 work on these cameras. In fact also 1/500 and 1/20 should be avoided on these cameras because of fundamental technical incompleteness. On these cameras not every shutter speed can be calibrated independently, as on the M cameras.
Erik.
Erik is this true of the original Leica II? Because I've just sent mine back to the repair shop for the third time to have the 1/500 speed adjusted. I asked the repairman if it was a flaw with the engineering of the camera and he said no, but that the speed would have to be adjusted to either over or under.
John Shriver
Well-known
The better bearings, and the shutter brakes, certainly do improve the accuracy and repeatability of the IIIa shutter at 1/1000.
But really the main problem of the IIIa shutter at those high speeds is that the only way to fine-tune the length of the slit is my moving the curtains on the drums, and that's a very tedious way to do it. Same applies on most models of the Canon bottom-loaders.
But it's not impossible to get reasonable performance at 1/1000 on a IIIa. Yeah, it may really be 1/750. (If the slit is so narrow that it's 1/1250, you'll get diffraction problems.)
But, it is vastly easier to adjust 1/500 and 1/1000 on a IIIc or later, due to the eccentric cams on the second curtain latch.
So the way I'd put it is that it's not economically practical to have a IIIa with a highly accurate 1/1000 shutter speed.
But really the main problem of the IIIa shutter at those high speeds is that the only way to fine-tune the length of the slit is my moving the curtains on the drums, and that's a very tedious way to do it. Same applies on most models of the Canon bottom-loaders.
But it's not impossible to get reasonable performance at 1/1000 on a IIIa. Yeah, it may really be 1/750. (If the slit is so narrow that it's 1/1250, you'll get diffraction problems.)
But, it is vastly easier to adjust 1/500 and 1/1000 on a IIIc or later, due to the eccentric cams on the second curtain latch.
So the way I'd put it is that it's not economically practical to have a IIIa with a highly accurate 1/1000 shutter speed.
colyn
ישו משיח
The better bearings, and the shutter brakes, certainly do improve the accuracy and repeatability of the IIIa shutter at 1/1000.
But really the main problem of the IIIa shutter at those high speeds is that the only way to fine-tune the length of the slit is my moving the curtains on the drums, and that's a very tedious way to do it. Same applies on most models of the Canon bottom-loaders.
This is why a pre-IIIc needs to be sent to a factory trained Leica tech when these models need shutter replacement. They have the proper tools needed to adjust the exact width of the slit.
I made my own years ago..
But it's not impossible to get reasonable performance at 1/1000 on a IIIa. Yeah, it may really be 1/750. (If the slit is so narrow that it's 1/1250, you'll get diffraction problems.)
Acceptable range is 20-25% so getting exactly 1/1000th and having the lower speeds within range is next to impossible.
But, it is vastly easier to adjust 1/500 and 1/1000 on a IIIc or later, due to the eccentric cams on the second curtain latch.
Agreed..
So the way I'd put it is that it's not economically practical to have a IIIa with a highly accurate 1/1000 shutter speed.
I agree here too. The shutter however if repaired properly can be within the 20-25% range.
One additional comment to Erik. Leica shutters from the model IIIc through the IIIf. The IIIg I am not sure since it is a slightly newer design. The shutter travels across the aperture at approx. 1/30th second. The pre-IIIc does in fact travel across the aperture 1/20th but this does not mean the shutter is unreliable if properly serviced. All closing curtain springs of all models are tensioned at 1 3/4 turns. Opening curtain spring tension will only vary 1/4-1/2 turn. The reason the opening curtain tension is set higher is because it has to move more parts than the closing curtain.
These facts can be verified by reading any official Leica repair manual..
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colyn
ישו משיח
Because I've just sent mine back to the repair shop for the third time to have the 1/500 speed adjusted.
One thing that can cause this is the use of a cheaper grade of shutter curtain material which will stretch which will release some tension on the springs.
Many non-Leica trained techs use the cheapest material they can find. I buy all of my shutter/tape material from Aki-Asahi..
I asked the repairman if it was a flaw with the engineering of the camera and he said no, but that the speed would have to be adjusted to either over or under.
I'd find someone else who knows how to do the job right..
Erik van Straten
Veteran
Erik is this true of the original Leica II? Because I've just sent mine back to the repair shop for the third time to have the 1/500 speed adjusted. I asked the repairman if it was a flaw with the engineering of the camera and he said no, but that the speed would have to be adjusted to either over or under.
It is not possible to adjust the speeds of a I, II, III, IIIa or IIIb individually, only the spring tension for the whole range can be varied. It is however not very important to have exact speeds, as long as the exposure over the whole frame is even. That is ofcourse more important than exact speeds.
Erik.
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