[Digikam-users] Pentax PEF vs DNG in digikam

[Gilles Caulier]

2011/9/27 Karl Günter Wünsch <kgw at mineralien-verkauf.de>:
> On 09/27/11 14:37, sleepless wrote:
>> Hi list,
>>
>> If I convert my PEF files to DNG, they look very different. DNG looks
>> darker.
>> It is both the same image, both RAW and both lossless. I think it should
>> look the same. Can someone explain why it does not.
> Because the conversion PEF to DNG loses meta data which will determine
> how the image will be processed. In this context the conversion is a
> lossy one!

Definitively NO.

DNG is not lossy format, especially metadata. All is preserved, as markernotes.

The problem is the way  to demosaicing and post process DNG. It sound
like not all process is done in DNG against PEF. This is why image is
dark (no gamma and WB adjustements). These informations are taken in
makernotes, of course.

How to solve it. libraw used by digiKam must be patched in to use
makernotes, for all possible camera makers. This is a huge job, not
simple.

Gilles Caulier