I have an old Canon EOS EF 300mm f/4L USM (non IS) telephoto lens (1997?) + Extender EF x1.4 III.
Darkroom information line and Image Information -> lens display this as Canon EF 300 mm with focal length 420 mm. Can I change this?
When I use this with a Canon 5D mk IV camera, the CR2 raw files have these EXIF tags:
- Lens Type: Canon EF 300mm f/4L USM
- Lens Model: EF300mm f/4L USM +1.4x III
- Lens ID: Canon EF 300mm f/4L USM + 1.4x
- Focal Length: 420.0 m
I use the Darktable variables (darktable 4.9 user manual - variables):
$(LENS) and $(EXIF_FOCAL_LENGTH)
This is displayed, in darkroom information line and in Image Information -> lens and as:
$(LENS) = Canon EF 300mm f/4L USM
$(EXIF_FOCAL_LENGTH) = 420 mm
Is this standard and intended? Or is it different for each combination of camera and lens and extender?
An example CR2 raw is attached. This file is licensed Creative Commons, By-Attribution, Share-Alike.
0Y8A1270.CR2 (36.4 MB)
I am not after any lens correction, only to get the lens to show up as Canon EF 300mm f/4L USM + 1.4x, if the extender is used, in darkroom information line and in `Image Information → lens.
