Archived posting to the Leica Users Group, 2012/12/10
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Herbert that is correct. Camera firmware never changed the in camera compression options. FWIW I use uncompressed DNG only in my M9 too. cheers Geoff On 10/12/2012, at 18:06, Herbert Kanner <kanner at acm.org> wrote: > Thanks Geoff. I take it then that it's the RAW processor in Lightroom and > not a camera firmware update that introduced the lossless compression. I > think that change was between LR2 and LR3. > > Re the compression from 16 (actually only fourteen bits of data in a 16 > bit container) to 8 bits being undetectable, I believe it, but I have > plenty of disk space; at the rate I'm shooting, disk space will outlive > me. However, I tried compressing in the camera in the hope that I would > see a speed-up, i.e. an increase in the number of continuous exposures > that could be made before the camera stopped dead because of a full > buffer. I could not see a noticeable change in this number between > compressed and uncompressed, so I just reverted to uncompressed for no > particularly valid reason. > Herbert Kanner > kanner at acm.org > 650-326-8204 > > Question authority and the authorities will question you. > > > > > On Dec 9, 2012, at 1:23 PM, Geoff Hopkinson wrote: > >> Herbert you have several items in there. >> Firstly if you use compressed DNG set in camera you give up almost nothing >> to gain the savings in file sizes. Some argue that you cannot see any >> difference at all. While it is technically lossy, this does not mean the >> change is significant and there is no futher loss on resaving, unlike >> where >> you save new versionsa as new JPGs.. >> Secondly on import in an Adobe raw processor (ACR or LR) truly LOSSLESS >> compression is applied. In recent program versions that is the default >> (and >> now only) process because there is no downside at all. >> If you open previously uncompressed on import DNGs and do some editing, >> for >> example a WB change that LOSSLESS compression is applied. >> Thirdly , whether you originally shot with your camera set for compressed >> or uncompressed DNGs, those files are further losslessly compressed by the >> Adobe program on import (or first editing and saving for earlier program >> versions). >> >> Cheers, >> Geoff >> http://www.pbase.com/hoppyman >> >> >> >> On 10 December 2012 06:39, Herbert Kanner <kanner at acm.org> wrote: >> >>> Hi LUGers, >>> >>> I'm looking for some enlightenment from anyone who knows. The question >>> has >>> to do with the size of Leica DNG files. Back in August, 2010, I had a set >>> of DNGs all but one of which were 36.4 MB in size. All of those taken >>> the >>> same afternoon at the same general location. Similarly, using Leica's >>> compression, in December, 2011, I found a set of DNGs taken the same day, >>> at 18.3 MB. >>> >>> Then, in November, 2011, there was a set taken the same day, where the >>> file sizes varied from 19.6 to 23.1 MB. Was this a result of a firmware >>> update in which Leica probably introduced LOSSLESS compression? To round >>> up >>> the picture, I found a set in August, 2012, where the size range was 8.5 >>> to >>> 10.3 MB, undoubtedly where I set "compressed DNG" on the camera. >>> >>> >>> >>> Herbert Kanner >>> kanner at acm.org >>> 650-326-8204 >>> >>> Question authority and the authorities will question you. >>> >>> >>> >>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information