Setting MaxApertureValue for Large Aperture (< 1) Manual Lenses

[sam]

I have a Canon FD 50mm f/1.2 lens with a Metabones focal reducer which gives about an one stop more light.

So, I'd like to set this value to 0.8 for this combo.

Code Select Expand


exiftool -MaxApertureValue=0.8 $image
Warning: Must be a positive number for ExifIFD:MaxApertureValue


[Hayo Baan]

There is a problem with the EXIF specification at this point; it simply does not allow for aperture values > 1. This is a grave oversight as not only do lenses with apertures > 1 really exist, they can also be fabricated using converters like you do.

Other than writing the info into the relevant xmp tags, I do not see a solution for you