Distance to subject from EXIF?

[Gregory]

hi.

does anyone know if it's possible to calculate the distance to the photographed subject from the nodal point based on EXIF data? shouldn't today's digital cameras be able to calculate this and include it in the EXIF?

there are times when I would like to have this information for self-learning purposes, for example when reviewing the DoF effect.

regards,
Gregory

[Panopeeper]

I know only how Canon cameras handle this.

Earlier there was no data about the focusing distance. Now the 1DMkIII, 40D and 1DsMkIII record the distance with most lenses. However, they don't record it in Exif but in the camera specific data (MakerNote), the structure of which is undisclosed, though some people reverse engineer most of it.

Canon's DPP displays the distance, but only on a slider, not numerically; it is part of the lens aberration correction process.

I guess the Exif viewer programs will soon display this data.