Luminous Landscape Forum

Equipment & Techniques => Beginner's Questions => Topic started by: markgoble on August 05, 2010, 06:27:44 pm

Title: DNG FILES
Post by: markgoble on August 05, 2010, 06:27:44 pm

I have been reading some older posts on the subject of DNG files, but wanted to get current thoughts from the Pros.

Is there any loss of quality by switching my Raw files to DNGs?
 Also, should back up be done on both the raw and the dng?

Thanks,

Mark

Title: DNG FILES
Post by: deejjjaaaa on August 05, 2010, 07:32:22 pm

Quote from: markgoble

I have been reading some older posts on the subject of DNG files, but wanted to get current thoughts from the Pros.

Is there any loss of quality by switching my Raw files to DNGs?
 Also, should back up be done on both the raw and the dng?

Thanks,

Mark

Eric Chan, who is present here as MadManChan, once posted ( http://forums.adobe.com/message/1210133#1210133 (http://forums.adobe.com/message/1210133#1210133) ) :

""...for archival purposes I recommend (and practice) safely storing the  original raw files in the form that they came off the camera, whether  they be DNG or non-DNG..."

now he is Adobe employee, so he probably knows better  

Title: DNG FILES
Post by: stamper on August 06, 2010, 04:11:55 am

Quote from: markgoble

I have been reading some older posts on the subject of DNG files, but wanted to get current thoughts from the Pros.

Is there any loss of quality by switching my Raw files to DNGs?
 Also, should back up be done on both the raw and the dng?

Thanks,

Mark

I don't think that addressing a question to the "Pros" is the best thing to do? I and others like me aren't "Pros" but might be able to answer the question. Does it disbar me from answering it?

Title: DNG FILES
Post by: NikoJorj on August 06, 2010, 09:04:36 am

As I'm only an amateur I won't waste the pro's bandwidth :
-No (but DON'T tick the "linear" checkbox)
-Yes (some more backup never hurts)

Title: DNG FILES
Post by: deejjjaaaa on August 06, 2010, 12:37:55 pm

Quote from: NikoJorj

-No (but DON'T tick the "linear" checkbox)

actually not "NO", Adobe DNG converter discards some raw data (for example data read off masked to light part of the sensor) for some raw files (for Nikon's .NEF/Pentax's .PEF it does), so if you are using (or will need to use sometime in the future) non Adobe tools for raw conversion, etc you might find out that the data is lost... chances are small, but do not mix using DNG as an intermediate stage in your workflow w/ using DNG for archival purposes w/o keeping what was created by your camera's firmware.

Title: DNG FILES
Post by: NikoJorj on August 06, 2010, 12:59:28 pm

Quote from: deja

Adobe DNG converter discards some raw data (for example data read off masked to light part of the sensor)

I'd be glad to read some source or confirmation ; the existence of DNGRecoverEdges (http://www.luminous-landscape.com/contents/DNG-Recover-Edges.shtml) made me think the opposite (but is no proof).

Title: DNG FILES
Post by: markgoble on August 06, 2010, 02:13:33 pm

Quote from: stamper

I don't think that addressing a question to the "Pros" is the best thing to do? I and others like me aren't "Pros" but might be able to answer the question. Does it disbar me from answering it?

Everyone, thanks for the input. I'm sorry if i offended any one, what i meant by pros were people that were light years ahead of me in post processing knowledge. I should have used the word knowledgeable rather than pros.   My bad


Anyway, thanks again, i always really appreciate the responses.

Mark

Title: DNG FILES
Post by: deejjjaaaa on August 07, 2010, 03:28:34 pm

Quote from: NikoJorj

I'd be glad to read some source or confirmation ; the existence of DNGRecoverEdges (http://www.luminous-landscape.com/contents/DNG-Recover-Edges.shtml) made me think the opposite (but is no proof).

it does not recover masked to light areas , which do not contain any image - but those areas can be used to correct various noise/banding issues w/ the raw data specifically @ high ISO... one of the applications that is actually using that information is described here  http://forums.dpreview.com/forums/readflat...thread=32705881 (http://forums.dpreview.com/forums/readflat.asp?forum=1036&thread=32705881)    ( make sure to read the whole tread - postings from GordonBGood, the author )...  you might find interesting this thread : http://forums.dpreview.com/forums/readflat...thread=34540534 (http://forums.dpreview.com/forums/readflat.asp?forum=1018&thread=34540534)  ( make sure read the whole thread - postings from GordonBGood and from C Vermillion - who is a developer from Bibble Labs - BibblePro raw converter ) ... stripping of the said information from .NEF files was confirmed by Gabor Schorr ( author of Rawnalyze ) - read here http://forums.adobe.com/thread/528900?tstart=0 (http://forums.adobe.com/thread/528900?tstart=0)  (his nick is Panoholic there - and his nick is Panopeeper here @ LL)