Leica M240 + Sony dream lens = not showing 0.95 on metadata

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randolph

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anyone else having problems with an encoded dream lens showing f/1.2 in metadata but the ring is physically set at f/0.95?
 
Not exactly sure what lens you are talking about, but the recorded aperture of any lens is simply a guess on the part of the camera, even if every lens you use is 6 bit coded. Half or more of the time the aperture setting shown in the EXIF data on my images using the M262 is anywhere from a little to a lot off, with f2 almost always showing as f2.4.

It's just a limitation of the system's ability to be all that accurate when recording the aperture setting.
 
Did you mean Canon 50/0.95, Randolph? [the dream lens]
I am unaware of a vintage Sony 50mm/0.95 lens.
 
Of course one solution to the inaccurate aperture info in the metadata would be to upgrade to the M10. Then there would be no aperture info in the metadata. :)
 
Luke_Miller said:
Of course one solution to the inaccurate aperture info in the metadata would be to upgrade to the M10. Then there would be no aperture info in the metadata. :)
Click to expand...

I wish Leica would give an update for all current models (M262 in my case) to do this. You'd think it wouldn't hurt also giving the M10's manual coding ability to set one uncoded lens to be used without having to change the camera manually as well. I could understand them not if every possible Leica lenses was coded, but they're not by a long shot. I'd love to set that for my 135mm f4 Tele Elmar, the one uncoded Leica lens I do use.

My plans are to eventually (later this year) have an M10, just not today.
 
My guess is that the aperture shown is probably the rough T/stop, since it's measuring the transmission based on the light passing through the lens compared to the real-world light levels, right?
 
Corran said:
My guess is that the aperture shown is probably the rough T/stop, since it's measuring the transmission based on the light passing through the lens compared to the real-world light levels, right?
Click to expand...


I don't think it's even that. Looking at the data from my M240, most of the time it seems to be a wild guess.

No electronic connection between camera and the lens means it has no accurate idea what aperture was used.
The coding is only useful for lens profiles.
 
I guess so. The few times I've looked at it on my M9, it seemed relatively close except for at wider stops. There's a little circle near the Red Dot that looks like a sensor of some type, so my assumption was that it was a small meter that measures the light levels and compares it to the light coming through the camera reading on the internal meter. But, that was admittedly a complete guess. And thinking about it now, I suppose I could test that given some black tape. And maybe things changed between the M9 and M240.

Personally I have no reason to know exactly what aperture I was using for a given photograph generally.
 
The M sensor averages; the lens has vignetting that drags the average down. Most lenses show about 1/3 stop slower, sometimes more. And yes, it's a measure of the overall T/stop in a crude kind of way.
 
Gregm61 said:
I wish Leica would give an update for all current models (M262 in my case) to do this. You'd think it wouldn't hurt also giving the M10's manual coding ability to set one uncoded lens to be used without having to change the camera manually as well. I could understand them not if every possible Leica lenses was coded, but they're not by a long shot. I'd love to set that for my 135mm f4 Tele Elmar, the one uncoded Leica lens I do use.

My plans are to eventually (later this year) have an M10, just not today.
Click to expand...

Greg,

Which version the firmware you have ?

Checked with my M (type 262) firmware 1.0.0.7 (from last dec.2017), the Tele-Elmar 4/135 in manual selection as 135f/4 11851/11861
 
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