Stupid question re aperture

[fordfanjpn]

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I noticed this before with my M11M but for some reason it didn't register until now. With my camera set to f8, 1/1000, Auto ISO, when I open the images in Lightroom Classic, Lightroom shows a variety of different f-stops for the images, even though the lens is set to f8 for all of them. Is that because the camera itself is not recording the aperture information in the files, or does Lightroom just not pay any attention to that and make something up for the aperture value? I guess it doesn't really matter that much, but it would be nice if the correct information was stored in the file, or read by Lightroom. FYI, I'm shooting an M11 Monochrom with an Elmarit 28mm f2.8 lens. 

[Smogg]

The camera has no way of knowing the exact aperture you have set on your M lens. Lightroom just makes a guess about the aperture.

[Eoin]

The camera has no way of knowing what aperture you set as there is no electronic or mechanical communication between lens and body to that effect.

The F stop value you see in the raw processor is the best guess the camera has made for the aperture (light) and other exposure parameters you physically set on the lens & Camera.

[fordfanjpn]

3 minutes ago, Smogg said:

The camera has no way of knowing the exact aperture you have set on your M lens. Lightroom just makes a guess about the aperture.

Thanks for the quick reply. I'm relatively new to Leica so my experience is primarily with other cameras that know what the aperture is set to. I appreciate you setting me straight on this. Just out of curiosity, would this also apply to a Q, or do those cameras know what the aperture is set to? 

Thanks again for your help. I'm constantly amazed and impressed by the depth of knowledge on this forum. 

 

[JNK100]

As others have said, the camera makes an estimate as there is no transfer of this information between the lens and the camera.

[fordfanjpn]

2 minutes ago, Eoin said:

The camera has no way of knowing what aperture you set as there is no electronic or mechanical communication between lens and body to that effect.

The F stop value you see in the raw processor is the best guess the camera has made for the aperture (light) and other exposure parameters you physically set on the lens & Camera.

Thanks. I had mistakenly assumed that because the Leica lenses are coded that they talk to the camera, but in retrospect, I can see that I was wrong about that. Live and learn. 

[JNK100]

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1 minute ago, fordfanjpn said:

Thanks for the quick reply. I'm relatively new to Leica so my experience is primarily with other cameras that know what the aperture is set to. I appreciate you setting me straight on this. Just out of curiosity, would this also apply to a Q, or do those cameras know what the aperture is set to? 

Thanks again for your help. I'm constantly amazed and impressed by the depth of knowledge on this forum. 

 

This does not apply to the Q. Accurate data is transferred. The M mount goes back to 1954 hence the lack of transfer.

[JNK100]

1 minute ago, fordfanjpn said:

Thanks. I had mistakenly assumed that because the Leica lenses are coded that they talk to the camera, but in retrospect, I can see that I was wrong about that. Live and learn. 

The coding is only to tell the camera which lens is fitted.

[250swb]

You need an electronic connection between the lens and the camera for the correct aperture to be displayed in the EXIF file. So all AF digital cameras will have it, manual focus digital cameras won't. If you are using Auto ISO or Auto Exposure the readings are more likely to be out because there are more variables for the camera to guess at, more consistent aperture and accurate guesses will be if you have a set ISO and a set shutter speed. But who cares anyway?

Edited September 1 by 250swb

[jaapv]

Yes, the camera uses the outside sensor to compare with the actual exposure. So it is not just a guess, but an educated one. Another function of that sensor is to set flash intensity for TTL flash 

[pippy]

15 minutes ago, jaapv said:

Yes, the camera uses the outside sensor to compare with the actual exposure...

Just to illustrate the 'Brightness Sensor' as mentioned by Jaap it is the small circular 'window' highlighted here in the green box;

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It might be worth mentioning that if Colour-Contrast / ND / Polarising Filters (etc.) are being used the recorded aperture guesstimate will be even further out than usual...

Philip.

[jaapv]

BTW there are no ( well, very few) stupid questions, only stupid answers. Watch this space for me to provide some 😅

[fordfanjpn]

2 minutes ago, jaapv said:

BTW there are no ( well, very few) stupid questions, only stupid answers. Watch this space for me to provide some 😅

Thanks. I've read a lot of your posts and I've never seen you say anything stupid. Quite the contrary. Always looking forward to reading more. 

[M11 for me]

And note that this aperture indication in Lightroom was left out quite a while. Was it with the M10?

And after there was so much push back Leica decided to re-introduce that "feature" again.

But to my experience it is not good for much as the deviation from the real setting to that guess is quite big some times. 

[marchyman]

6 hours ago, Smogg said:

Lightroom just makes a guess about the aperture.

The camera makes the guess. Lightroom simply reports what it reads in the image metadata.

When I clean the rangefinder and viewfinder windows I also wipe the lens cleaning cloth across the sensor.  Don't know if it helps, but I figure it won't hurt.

[earleygallery]

No such thing as a stupid question, but I would suggest reading the manual!

[evikne]

This typical question is also answered in this Q&A thread, but it has gradually become quite extensive and confusing: