[Digikam-users] Re: tagging: cr2 vs dng

[Remco Viëtor]

on Sunday 02 January 2011, Jim Dory wrote: 
> (...)
> So, when I tag DNG files in Digikam - it takes an incredibly long time
> when tagging several at once. I convert all my CR2 files to DNG then
> move off the CR2 files to an external backup and forget about them and
> just have DNG in Digikam. Unfortunately I've done this to many
> hundreds of photos before tagging them - and now face the painfully
> slow tagging process. Easy workaround in the future and something I
> now realize I should have been doing is just first tag the CR2s before
> converting -as the tags are preserved during the conversion to DNG.
> 
> So not sure if my setup is wrong or I'm doing something wrong, but not
> sure why DNG takes so long in applying tags. I am using Adobe's DNG
> converter as I have not yet figured out how to get Digikam's DNG
> conversion to work as well - I'm not happy with color/white balance.
> ...

Not sure if I'm on the right track, but the speed difference might be due to 
Digikam not writing the tags to CR2 files, while it can (and does) write them 
to the DNG files. In both cases the database will be updated as well, but that 
is relatively fast. 

This would also imply that tagging the CR2 files and then converting with 
Adobe converter wouldn't help (I'd not expect the Adobe converter to use the 
Digikam database)

Good luck