(Maybe) New entry for Sony metadata (Focus position from image plane)

[Takapapatapaka]

Hello everyone !

(Newbie here, so if there's anything wrong with my post, tell me and I'll change it)

I was digging through metadata of video clips shot with Sony AX53, looking for the focal length as it is missing from the official Catalyst Browse app.

I think I found an unknown entry with exiftool v12.80, labelled as "Sony rtmd 0x8001". It changes along with the "Focus position from image plane" that Catalyst Browse indicates.

	Shot 1	Shot 2	Shot 3
Catalyst "Focus position"	0.8m	1.4m	2.5m
Exiftool "Sony rtmd 0x8001"	54048	54648	55748

I don't have any idea of why it is decoded this way by Exiftool but it seems to me that the focus position in decimeters corresponds to the second and third digit of the Exiftool output, minus 32.

I searched on this forum if it was already discussed, and it seemed not, so I make this post. Hope this can be helpful !

PS : In the end, I guess there's no way to get focal length of a Sony clip if it is not provided directly in the Catalyst app. If anyone reading this knows about it and can confirm or not, I would be glad to get a bit of your knowledge !

[Phil Harvey]

Interesting, but this would be a really odd way to encode the focus distance.  I think that more sample points over a wider range of distances would be necessary to figure this one out.

- Phil