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View Full Version : Distance to subject info in EXIF data?



Roger Clark
03-29-2008, 11:53 AM
Hi,
Does anyone know if the distance to the subject is recorded in the EXIF data for digital
cameras? On the lens barrel, we typically see the distance indicator, but is that distance
recorded in the image file? In particular, since I use Canon cameras, I'm interested in that
value for Canon 1D Mark II, 30D, and 40D cameras.

Roger

Alfred Forns
03-29-2008, 12:33 PM
Good question Roger Never seen it recorded Would be informative !!!

Jim Poor
03-29-2008, 06:34 PM
Way back when I first started, a program called Digital Pro (I think version 3 at the time) advertised that it could read the distance information. I got the program and had no luck with the distance read out. I contacted the maker, and he told me that Nikon had moved the location of the data and until someone "finds it" again, it won't be readable.

It has to record somewhere because Capture NX advertises that it uses the data to assist in certain automatic corrections like vignetting removal.

Henry Wintringham
03-29-2008, 06:44 PM
The current version of Breezebrowser Pro provides the distance in meters in the EXIF data. I recall seeing it in previous versions as well.

Doug West
03-29-2008, 08:11 PM
The current version of Breezebrowser Pro provides the distance in meters in the EXIF data. I recall seeing it in previous versions as well.

If you can point out where, that would be great. I see the focal length, but
thats not the distance to the subject.

Doug

Mike Tracy
03-30-2008, 11:55 AM
If you can point out where, that would be great. I see the focal length, but
thats not the distance to the subject.

Doug

This is how it is displayed on the right side of my screen. I highlighted the distance info. I run the most recent version of Breeze Browser Pro

2008:03:24 17:39:45
700mm
Subject dist: 55m
1/2000 sec, f/5.6
Mode: Av
Metering: Partial
Exp comp: +1
ISO: 640
AF mode: AI Servo AF
Drive: Continuous
White balance: Auto
Flash: Off
File size: 12.7MB
Image size: 3888 x 2592
Color space: AdobeRGB
Saturation: Normal
Sharpness: 4
Contrast: Normal
Tone: Normal
Custom Functions:
CFn I-3: ISO range enabled
CFn I-9: Registered usable shooting modes enabled
CFn I-10: Registered usable metering modes enabled
CFn I-12: Registered shutter speed range enabled
CFn I-13: Registered aperture value range enabled
CFn III-2: AI Servo tracking sensitivity: fast (+1)

Henry Wintringham
03-30-2008, 05:40 PM
Thanks Mike. I should have mentioned that this seems to have been available in every version of Breezebrowser that I've owned and I''ve been using it since 2002.

Roger Clark
03-30-2008, 09:23 PM
Mike,
With what camera bodies are you seeing the distance recorded? The is a post from Chuck Westfall in another forum I found with google today where he says he is unaware of any current Canon DSLRs actually reporting distance information. Apparently there have been numerous requests to Canon for this info. Early on some Canon lenses did report distance while others did not, and on those lenses apparently garbage got written in the exfi for the distance. So canon changed the exif to not report it, or at least that is what people seem to be reporting in other forums and that seems confirmed by Chuck (I think a couple of months ago--I'd have to search for the link again.)

I downloaded the latest version of jhead and went through some old photos. I found some 10D images where jhead reported distance values, but 30D and 1D Mark II images showed no distance.

---very frustrating.

Roger

Henry Wintringham
03-30-2008, 10:22 PM
Roger, I've had the information reported for my old D60 body and it appears for my 1Ds Mk III. I have seen figures reported for all the lenses I own, though I can't vouch for their accuracy. The distance informaton appears right for those shots I've looked at, but I haven't paid that much attention to the distance EXIF information. I wonder how far off the data is supposed to be -- the numbers have looked pretty reasonable to me.

Mike Tracy
03-31-2008, 05:30 AM
Mike,
With what camera bodies are you seeing the distance recorded? The is a post from Chuck Westfall in another forum I found with google today where he says he is unaware of any current Canon DSLRs actually reporting distance information. Apparently there have been numerous requests to Canon for this info. Early on some Canon lenses did report distance while others did not, and on those lenses apparently garbage got written in the exfi for the distance. So canon changed the exif to not report it, or at least that is what people seem to be reporting in other forums and that seems confirmed by Chuck (I think a couple of months ago--I'd have to search for the link again.)

I downloaded the latest version of jhead and went through some old photos. I found some 10D images where jhead reported distance values, but 30D and 1D Mark II images showed no distance.

---very frustrating.

Roger

Shows up with my MKIII but not the 20D.

Jim Poor
03-31-2008, 07:13 AM
I believe I read somewhere that distance reporting is a function of the lens type rather than the camera body. I believe it was when I was looking at Capture NX.

Mike Tracy
03-31-2008, 07:45 AM
I believe I read somewhere that distance reporting is a function of the lens type rather than the camera body. I believe it was when I was looking at Capture NX.

No time to really put it to the test because I am taking off for work but here is what I quickly found.

1DMKIII : quick shots with EF 500with 1.4x, EF100-400, 70-200 f/2.8 all had distance data intact.
All files taken with 20D with same lenses did not display distance. I have 5 additional lenses I could try but it seems like it is camera specific.