CL Auto-ISO not working with "dumb" MF lenses

[robgo2]

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I have not used my CL in over a year, thanks to Covid-19, but I took it out of the drawer today in anticipation of doing some family photography later this month.  I mounted several Voigtlander M lenses via an M to L adapter.  With the camera set on A and Auto-ISO, I noticed that the Auto-ISO remained fixed at ISO 100, even though the maximum ISO is set to be 6400. I am able to adjust the ISO setting manually.  With native TL lenses, the Auto-ISO works as expected.  I feel certain that I am missing something here but don't know what it could be.  

Help, please.  

[lct]

Shutter speed is slow i guess. You may wish to try a faster one.

[AdHox]

1 hour ago, lct said:

Shutter speed is slow i guess. You may wish to try a faster one.

Rob, I note that you’re using A mode so your CL should be setting the shutter speed & ISO. However if the aperture is wide enough then its algorithms may decide that the required shutter speed is still short enough that it doesn’t require a higher ISO. What happens when you close down to f/22?

Edited May 9, 2021 by AdHox

[robgo2]

I think that I have figured it out--sort of.  

In my Auto-ISO settings, I have selected a minimum shutter speed of 1/2f.  However, with a lens that has no connection to the camera body, the focal length is unknown.  Hence, the shutter speed responds to the light available at any given aperture, and the ISO does not move off of 100.  But here is the kicker.  When I manually enter a lens profile for the correct focal length, the ISO does change with the light, but the minimum shutter speed ignores the 1/2f limit.

I'm still scratching my head.

[lct]

Did you try auto iso in M mode? Works fine on all my cameras including the CL with M or LTM lenses. 

[ramarren]

37 minutes ago, robgo2 said:

I think that I have figured it out--sort of.  

In my Auto-ISO settings, I have selected a minimum shutter speed of 1/2f.  However, with a lens that has no connection to the camera body, the focal length is unknown.  Hence, the shutter speed responds to the light available at any given aperture, and the ISO does not move off of 100.  But here is the kicker.  When I manually enter a lens profile for the correct focal length, the ISO does change with the light, but the minimum shutter speed ignores the 1/2f limit.

I'm still scratching my head.

Yes, you must select a lens profile (or have Automatically recognized, coded lenses) for whatever lens you fit if you are going to use the 1/[xf] AutoISO settings so that the camera knows what f to use as a discriminator for upping the ISO setting. You can switch to a time-based minimum limit and then the camera will start raising the ISO when the light coming through the lens pushes the exposure setting to that level. 

G

[robgo2]

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1 hour ago, ramarren said:

Yes, you must select a lens profile (or have Automatically recognized, coded lenses) for whatever lens you fit if you are going to use the 1/[xf] AutoISO settings so that the camera knows what f to use as a discriminator for upping the ISO setting. You can switch to a time-based minimum limit and then the camera will start raising the ISO when the light coming through the lens pushes the exposure setting to that level. 

G

I have entered a lens profile, and what I get is the minimum shutter speed limit being ignored by the camera.  I do not recall having this problem with my SL.  It would appear is that the only solution is to set a specific minimum shutter speed for each lens, hoping that I can remember to do it every time I switch lenses.

[stevenkasapi]

I know this is an old topic, but I have the same issue if I use a 3rd party adapter - if I manually enter the lens type - the CL doesn't use the 1/2f setting for the min shutter speed, it locks the ISO at 100 when set to Auto. Same thing if I use a 3rd party L-mount manual lens (lie one of the TTArtisan lenses).

However, if I use the official Leica L-to-M adapter with coded lenses or with non-coded lenses and set the lens type manually, the camera does use the 1/2f min shutter speed on auto ISO.

Seems like a firmware but, but since the CL is discontinued I doubt there'll be a firmware update to fix it. 

Not a huge deal, I just set the min shutter speed on Auto ISO myself when needed, but just thought I'd let you know you're not alone. 

[lct]

The Leica adapter allows for auto iso to work fine with M  lenses. You don't have to set the lens type manually if your lens is correctly coded. Minimum shutter speeds may be ignored when the camera has not enough leeway for high isos. Suffice it to crank up the iso range then or to open the aperture wider. You can also set the shutter speed manually if needed. Not sure there is any firmware issue to fix from this viewpoint.

Edited July 18, 2023 by lct