Exif info

[Huss1100]

When I use my Sigma 50mm f1.4 lens on my 5D mk1 the the exif data knows it is a 50mm lens, but thinks the lens model is a EF17-35 f2.8 or Sigma.

When I use the same lens on my 1D mk2 the exif data knows the lens is a Sigma 50mm f1.4 EX DG.

Both camera's have the latest firmware.

Is it normal for a 5D mk1 not to recognise a Sigma 50mm f1.4 lens ?

 

[paulcamcas]

I've seen something like this before. What software are you using? PC or mac?

 

[Canon Bob]

The EXIF tag for the Canon EF17-35/2.8L is "169" whilst the Sigma 50/1.4 has a tag value of "169.4". When the 5D was produced, the body only sent the first 3 digits of the tag to the EXIF file....generally there weren't any 4 digit tags. The later bodies now read the final digit as more lenses have been added to the database.

Bob

 

[Huss1100]

I've seen something like this before. What software are you using? PC or mac?

Thanks Paul, it happens on my mac and the wifes pc.

The EXIF tag for the Canon EF17-35/2.8L is "169" whilst the Sigma 50/1.4 has a tag value of "169.4". When the 5D was produced, the body only sent the first 3 digits of the tag to the EXIF file....generally there weren't any 4 digit tags. The later bodies now read the final digit as more lenses have been added to the database.

Bob

Thanks Bob, I thought it would be something like that. My 5D is newer than my 1D mk2. Yet the 1D recognises the lens.

 

[Canon Bob]

Thanks Bob, I thought it would be something like that. My 5D is newer than my 1D mk2. Yet the 1D recognises the lens.

It's simply that the 5D only adds a 3 digit lens tag to the EXIF. I'm pretty certain that the 1D2 did the same originally but maybe they had more space to play with when they updated the firmware.

Bob

 

[Huss1100]

Thanks Bob.

 

[paulcamcas]

Thanks Paul, it happens on my mac and the wifes pc.

Bob has nailed this one. I asked about the mac/pc because my 135mm F2L on my 5D2 shows up correctly when the exif is viewed on a pc but on a mac it shows as "Unknown (174) 135mm". I've checked the lens on my friend's 5D2 and his 135 on mine and all combos show the same, so I think it's a Mac thing.

 

[Thedodo]

My exif messes up if i put my 2x converter on my Tammy 70-200, but if i use the converter on any of my other lenses it seems to be fine!

 

[Canon Bob]

Bob has nailed this one. I asked about the mac/pc because my 135mm F2L on my 5D2 shows up correctly when the exif is viewed on a pc but on a mac it shows as "Unknown (174) 135mm". I've checked the lens on my friend's 5D2 and his 135 on mine and all combos show the same, so I think it's a Mac thing.

Lens tag value "174" is for the EF135/2 and "undefined Sigma lens" but there's no 174.1 etc so it's a shared value. I think that the MAC is actually telling the truth whilst the PC is making an assumption....it isn't 100% certain that the lens is a 135/2 but happens to be correct in your scenario.

Bob

 

[paulcamcas]

Lens tag value "174" is for the EF135/2 and "undefined Sigma lens" but there's no 174.1 etc so it's a shared value. I think that the MAC is actually telling the truth whilst the PC is making an assumption....it isn't 100% certain that the lens is a 135/2 but happens to be correct in your scenario.

Bob

Thanks Bob. That makes sense. Funny thing is, a few OSX versions ago the 135mm showed correctly (or the correct assumption was made) on my Mac too.