Scale Factor To 35 mm Equivalent

[linuxuser]

With a Pentax K-1 you can deside if you use fullformat or APS-C.

There is a composite value:

APS-C:
[EXIF]          0xc61e Default Scale                   : 1 1
[Composite]          - Scale Factor To 35 mm Equivalent: 1.5

FF:
[EXIF]          0xc61e Default Scale                   : 1 1
[Composite]          - Scale Factor To 35 mm Equivalent: 1.0

How is this "Scale Factor To 35 mm Equivalent" calculated? By some metadata? Is there an EXIF or XMP-field where this info can be written, except comment or similar text fields.

[linuxuser]

What does this field mean:

[EXIF]          0x00fe Subfile Type                    : Reduced-resolution image

It says with fullformat also reduced.

[Phil Harvey]

The Composite tags and the tags they are derived from are listed here.  ScaleFactor35efl is particularly complex, but the simplest way to set this is to write both FocalLength and FocalLengthIn35mmFormat.

The SubfileType gives the type of image in the given IFD.  Use -G1 to see which IFD.

- Phil

[linuxuser]

Thanks, I am testing, where I can write a crop-factor (the composite value) so that f-stop can read it. Any idea for a field? I assume an EXIF-tag could work, which I would try first before xmp.

[linuxuser]

I found something, -EXIF:CameraLabel is displayed as unknown tag and -XMP:Label works fine with f-spot.