Quote from: Phil Harvey on April 21, 2010, 07:53:04 AM
As stated in the documentation, this value may not be correct if the image has been resized by some software. For images straight out of the camera, it should be reliable.
- Phil
I wonder if it is really reliable. Apparantly
Composite:FocalLength35efl is reported wrong for photos I made yesterday with my Olympus E-1.
> exiftool -LensType -Aperture -Extender -FocalLength P7062961.orf
Lens Type : Olympus Zuiko Digital ED 50-200mm F2.8-3.5 SWD
Aperture : 4.9
Extender : Olympus Zuiko Digital EC-14 1.4x Teleconverter
Focal Length : 283.0 mm
> exiftool -FocalLength35efl -ScaleFactor35efl P7062961.orf
Focal Length : 283.0 mm (35 mm equivalent: 200.0 mm)
Scale Factor To 35 mm Equivalent: 0.7
> exiftool -ver
8.75
Because of the 1,4x converter I was able to extend the 200 mm physical focal length of this lens to 283 mm. This is reported correctly. But the actual 35-mm-equiv. focal length is 566 mm @ 4,9.
Quote from: Phil Harvey on April 19, 2010, 07:32:50 AM
The computation is based on the FocalPlaneX/YResolution tags unless the FocalLengthIn35mmFormat tag exists already in which case it is used.
- Phil
> exiftool -FocalLengthIn35mmFormat P7062961.orf
Focal Length In 35mm Format : 200 mm
Doesnt' the
FocalLengthIn35mmFormat-rule ignore crop-factors in general... and teleconverters? 8)
Hi Andreas,
Sorry for the delay in responding, I was on vacation.
I don't have any original E-1 samples with an extender. If you send one to me (philharvey66 at gmail.com) I will take a look. The calculation works for all E-1 samples I have on hand.
- Phil