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I use a Canon 60D, which is a crop-sensor DSLR. Does the metadata found in Lightroom or Bridge report the actual focal length or the crop-sensor equivalent?

For example, if the metadata says the focal length was 28mm, was it an actual 28mm or a crop-sensor 28mm [an actual focal length of 44.8mm]?

I know that lenses have a magnification value of 1.6 when used on a crop-sensor camera. I was just wondering if the focal length reported by the camera itself was actual or magnified.

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I have a 30D and can not find the equivalent focal length in Lightroom. I've seen that listed with the exif data on some sites like Flickr and now I'm guessing the site calculates that itself. –  David Hogue Mar 26 '13 at 6:15
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Flickr doesn't calculate focal lengths, it reads it from the EXIF data if it is there. Per EXIF specification the attribute FocalLength refers to Lens Focal Length. –  Peng Tuck Kwok Mar 26 '13 at 9:30
    
Also in the specification I see the attribute FocalLengthIn35mmFilm but honestly I've never seen it being used. –  Peng Tuck Kwok Mar 26 '13 at 9:32

3 Answers 3

The focal length is a physical measurement that's the same no matter what size the sensor, and that is what the camera will report.

The 35mm-equivalent focal length can be calculated from other EXIF information relative to a 24x36 frame.

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The focal length reported in the EXIF is the actual focal length of the lens, regardless of sensor. So if you have a 28mm lens as you say, then Lightroom will tell you the photo was taken at 28mm. You would then need to combine that with the Camera Model reported yourself and your knowledge of whether the camera is a full frame, APS-H, APS-C sensor, etc to work out the effective focal length.

Also don't forget when it comes to APS-C, most manufacturers use a multiplier of 1.5x except for Canon who use 1.6!

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Thanks so much! I'm in the market for a fixed, fast lens, and surveyed my photos to see what focal length I most shoot at--I came up with 28! So then I thought...is that really 28mm or actually 44.8mm? I used the metadata in Lightroom...this answers my question! I'll have to apply the 1.6 factor while shopping, but needed to know what I actually used. I shoot in commercial kitchens [very tight spaces] so I can't afford to get it wrong. Again, thanks! –  Margot Phillips Mar 26 '13 at 13:28
    
Glad to help! Since you say this answers your question - can you mark it as such? Thanks :) –  Mike Mar 26 '13 at 15:45
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@MargotPhillips: You say "I'll have to apply the 1.6 factor while shopping", but that shouldn't be the case. The lenses you're looking for are also sold by their real focal lengths. –  mattdm Mar 26 '13 at 19:47

The EXIF focal length stored in the metadata itself will be the real focal length. However, many software programs will automatically provide the equivalent, since there is also information on the sensor size available. The command-line utility jhead shows it like this:

$ jhead 20130317_k5ii_mksm2247.jpg |grep Focal
Focal length : 70.0mm  (35mm equivalent: 105mm)

Or, with exiftool:

Focal Length                    : 70.0 mm
Focal Length In 35mm Format     : 105 mm
Focal Length                    : 70.0 mm (35 mm equivalent: 105.0 mm)

As you can see, it's clearly labeled which is which. Any decent software which makes this conversion will likewise make it obvious, and it should be generally safe to assume that any focal length not marked as "equivalent" is real.

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