p.1 #1 · Does your M record accurate exposure info when using 6 bit coded lenses?
Am I the only one frustrated with this? I know it's not electronic transfer of info from the lens to the camera. But sometimes, when i shoot the Summilux wide open it records it as shot at F1.0
p.1 #2 · Does your M record accurate exposure info when using 6 bit coded lenses?
Jorge Torralba wrote:
Am I the only one frustrated with this? I know it's not electronic transfer of info from the lens to the camera. But sometimes, when i shoot the Summilux wide open it records it as shot at F1.0
Do you have similar experience?
I have never seen an aperture lower than the lens could shoot- It shows smaller apertures all the time- Never larger though. I even double checked in lightroom- no shots between f1-1.3 except on a expected lenses (Noctilux/Voight f/1)
p.1 #4 · Does your M record accurate exposure info when using 6 bit coded lenses?
No. There is no electrical connect between aperture ring and camera. For EXIF the camera makes a 'best guess' based on shutter speed and light reading. It is usually out 1 to 2 EV's in my experience.
p.1 #8 · Does your M record accurate exposure info when using 6 bit coded lenses?
1bwana1 wrote:
M will never give correct aperture numbers in EXIF data. Just a guess. But Shutter Speed, and ISO, and the other EXIF data should be correct.
my thoughts exactly. but knowing what lens is because of the 6 bit, the logic should be
p.1 #9 · Does your M record accurate exposure info when using 6 bit coded lenses?
Jorge Torralba wrote:
my thoughts exactly. but knowing what lens is because of the 6 bit, the logic should be
if ( f < 1.4 ) {
f = 1.4;
}
if ( f > 16 ) {
f = 16;
}
Thats a software thing or at least it looks that way to me.- The Exif shows the aperture value and max aperture-
F number shows the max is f/1. Not sure why there is two fields- one for aperture and one for F number. I guess technically those could be different values but thats not something I care to understand enough to determine mathematically
p.1 #11 · Does your M record accurate exposure info when using 6 bit coded lenses?
It does not take 6-bit code in consideration when the camera estimates the aperture. It’s always an estimation and very seldom gets it right. Basically the M cameras doesn’t know the working aperture.
Jorge Torralba wrote:
my thoughts exactly. but knowing what lens is because of the 6 bit, the logic should be
p.1 #12 · Does your M record accurate exposure info when using 6 bit coded lenses?
Fred Miranda wrote:
It does not take 6-bit code in consideration when the camera estimates the aperture. It’s always an estimation and very seldom gets it right. Basically the M cameras doesn’t know the working aperture.
I have never seen it go under the stated max/min aperture though Fred-
For example the only time I ever get an aperture under 1.4 is when shooting a Noctilux -
p.1 #13 · Does your M record accurate exposure info when using 6 bit coded lenses?
The above is simply logic to say,
Based on lighting condition the camera will estimate and tell you this was shot at f1.0 and 1/60 of a second.
But then the camera should go through the process of.
Since this is an estimate anyway you look at it, if i shot this at 1.0 at 1/60th of a second, and i know the max aperture on the lens is 1.4 based on the 6 bit code, i should display a value to 1.4 instead of 1.0.
Anyways, just curious if other experienced this. thanks for chiming in.
p.1 #14 · Does your M record accurate exposure info when using 6 bit coded lenses?
Jorge Torralba wrote:
The above is simply logic to say,
Based on lighting condition the camera will estimate and tell you this was shot at f1.0 and 1/60 of a second.
But then the camera should go through the process of.
Since this is an estimate anyway you look at it, if i shot this at 1.0 at 1/60th of a second, and i know the max aperture on the lens is 1.4 based on the 6 bit code, i should display a value to 1.4 instead of 1.0.
Anyways, just curious if other experienced this. thanks for chiming in.
I fully understood what you were saying in your algorithm logic. I just don't think it much matters either way.
p.1 #15 · Does your M record accurate exposure info when using 6 bit coded lenses?
I agree this isn't a big deal in practice it's an estimate anyway. I'd prefer my M11 just didn't bother recording an aperture.
At the same time, it's of a piece with the pattern of surprising and obvious programming issues in Leica's firmware that should be unacceptable in a camera at this price.
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p.1 #16 · Does your M record accurate exposure info when using 6 bit coded lenses?
Jorge Torralba wrote:
The above is simply logic to say,
Based on lighting condition the camera will estimate and tell you this was shot at f1.0 and 1/60 of a second.
But then the camera should go through the process of.
Since this is an estimate anyway you look at it, if i shot this at 1.0 at 1/60th of a second, and i know the max aperture on the lens is 1.4 based on the 6 bit code, i should display a value to 1.4 instead of 1.0.
Anyways, just curious if other experienced this. thanks for chiming in.
I agree it would be a good thing if Leica modified their guess at aperture in this way, but they don't. I have just learned to ignore the reported aperture when shooting a Leica M. It is wrong so often and by pretty big margins enough that I don't find it useful. I like that Leica M cameras can use the 6-bit code to identify the lens in the EXIF, and we do even get some useful adjustments that can be made easily in post-processing because of this code. If would be fine, however, if the camera never made the guess at aperture and Leica just reported the max aperture of the lens.
p.1 #17 · Does your M record accurate exposure info when using 6 bit coded lenses?
Leica seems to assume that what they're doing is about the best that can be done given that there is no electronic communication between the lens and the camera. In theory they could use the 6-bit coding to improve the camera's aperture estimation, but they never implemented that, even on the latest EV1 model.
Even then, the only real improvement would be preventing the camera from guessing an aperture faster than the lens's maximum aperture, so it would still be inaccurate.
This is actually one of the first things people notice when they try a digital Leica M for the first time. It comes up in almost all my reviews when I mention that the images were shot wide open but the EXIF says something different.
p.1 #19 · Does your M record accurate exposure info when using 6 bit coded lenses?
Hehe, this is my oldest complaint about the digital M’s. They put the ugly brightness sensor on the front of the top plate for the sake of inaccurate aperture EXIF data.
