exif data

[crittertoo]

using the m9 and the 0.95 noc, the exif data for the f is not correct when I am at f1.2 and below. 1.2 and 0.95 shows as 1.4 in lightroom, any knows what is going on? M9 is on latest firmware, all other lens works just fine...

thanks for you forthcoming comments

 

[Leigh]

Are you sure the problem is in the file?

Perhaps Lightroom doesn't understand fast lenses.

Download EXIFTOOL here http://www.sno.phy.queensu.ca/~phil/exiftool/
and use it to check the actual information in the image file(s).

- Leigh

 

[crittertoo]

thanks Leigh for the input. I have tried the exiftool, just to confirm that I am reading the right f value - the f values for the file concern are max aperture value?

 

[crittertoo]

just tried reading the dng again using exiftool. Lens Type : Noctilux-M 50mm f/0.95 ASPH is right. Max Aperture Value was given as 1.$ - something is wrong here. Anyone here seen similar symptoms with the M9 and the Noc 0.95?

 

[Leigh]

I have tried the exiftool, just to confirm that I am reading the right f value - the f values for the file concern are max aperture value?

I'm sorry. I'm not sure what you mean.

Do the files contain the correct information? If not, then the problem is in the camera software. I would suggest contacting the manufacturer or looking at their website.

It's interesting that the incorrect value is a standard f/stop size. It would appear that some software has that set as an upper limit.

- Leigh

 

[Paratom]

as far as I think to remember the f-stop value is only an approximate value anyways because it is calculated with the help of an external light sensor and the real light coming through the lens. I dont know how precise the calculation can be.

 

[crittertoo]

i will head to leica mayfair on fri to have them look at this. thanks for all your assistance

 

[panda81]

as far as I think to remember the f-stop value is only an approximate value anyways because it is calculated with the help of an external light sensor and the real light coming through the lens. I dont know how precise the calculation can be.

from what i've read before, this is the answer. the camera doesn't detect the actual aperture through electronic contacts (like what a dslr might do), but instead records the aperture value from approximate calculations based on light and other settings (iso, shutter speed). so, the recorded aperture can be different from what you actually used.

 

[Leigh]

On the digital cameras I've encountered, the camera body sets the lens f/stop based on exposure calculations or user input. That value appears in the EXIF data.

Since I'm not familiar with the camera under discussion in this thread, I don't know if that's true here or not.

- Leigh