View Full Version : Z depth


John Jay
October 30th, 2002, 08:20 PM
I have noticed Sony are including focal distance (Z depth) in the viewfinder on their cams lately and wondered whether focus information is encoded into the DV stream?

If so can it be accessed and what application reads this data?

The reason for asking is that it would be extremely useful for advanced keying applications like Boojou, Matchmaker, Mokey and the like?

Jeff Donald
October 30th, 2002, 09:00 PM
I'm not sure what you mean by focal distance. Do you mean focal length of the lens, measured in millemeters? Or do you mean the distance from the image plane (CCD) to the subject?

Jeff

John Jay
October 30th, 2002, 10:06 PM
I am resisting making a joke about circles of confusion here Jeff but I mean the latter as you expressed

<<the distance from the image plane (CCD) to the subject? >>


or to use Sony's term
"focal distance information" which appears in metres

Jeff Donald
October 31st, 2002, 06:58 AM
The data for the display is derived from the auto focus system and the data is not presently contained in the data section of DV tapes. But it is only a matter of time.

Jeff