On Wed, Nov 15, 2017 at 3:35 PM, Heiko Bauke <heiko.ba...@mail.de> wrote: > Hi, > > Am 15.11.2017 um 12:28 schrieb Roman Lebedev: >> >> On Wed, Nov 15, 2017 at 2:14 PM, Heiko Bauke <heiko.ba...@mail.de> wrote: > > [...] >>> >>> Contrary to the common believe that in-camera >>> corrections are applied to JPEGs but not to the RAW file, in-camera lens >>> correction in the EOS-1D X Mark II is applied to RAWs only. See >>> >>> https://snapshot.canon-asia.com/article/en/eos-5d-mark-iv-lens-aberration-correctiona-close-up-look-part-1 >> >> >> Can you quote that part where it says what you think it says? >> I don't see anything there about modifying the raw files. > > > the article is about in-camera lens correction. Lens corrections are stored > in the image data, it's not about storing meta data for lens correction in > post processing. Do not be confused by the fact that there is also a > software tool provided by Canon that implements the same kind of lens > correction algorithms for post processing. > > The term RAW file is not included explicitly in the article that I > mentioned. It is, however, highlighted that »The Digital Lens Optimizer > [...] made its debut as an in-camera feature on the EOS-1D X Mark II. At > that time, its effects could not be reflected in real time on JPEG images.« > I understand this statement as that the RAW file image data is affected. > The camera has a special hardware component to do the heavy math. This > would not be needed if just some meta data for lens correction in post would > be included into the RAW file. > > Furthermore, another Canon article (see > https://snapshot.canon-asia.com/article/en/eos-1d-x-mark-ii-in-camera-lens-optimization-for-high-quality-images > ) says > > »The processing ability of the Dual DIGIC 6 + image processing engines is > what makes in-camera image processing possible. They are capable of > processing the vast amount of data that is yielded from the 20-megapixel > sensor and the continuous shooting speed of 16 fps at a high speed, and > achieve in-camera RAW image development and real-time aberration correction. > A dedicated IC has been developed and employed to enable the incorporation > of different aberration correction features during in-camera RAW image.«
> How would you understand »in-camera RAW image development«? It does > definitely not refer to the lens correction to the JPEG, because this camera > does not have such a feature. You are just plain wrong here. Lens correction for the jpeg's was always there, provided the lens profile is stored in camera. > According to > https://photo.stackexchange.com/questions/35324/why-does-using-canons-digital-lens-optimizer-double-the-size-of-a-raw-file > in-camera lens correction in Canon cameras doubles the RAW file size, > because the processed image data is stored in addition to the unprocessed > RAW data. Those are just words, there is not a single confirmed fact there, e.g. exif dumps that would show that there is a two SubImages even though the DualPixel is disabled. But even if it is true, that violates your own words, since the original unmodified raw is still there. > Heiko Roman. > -- > -- Number Crunch Blog @ https://www.numbercrunch.de > -- Cluster Computing @ http://www.clustercomputing.de > -- Professional @ https://www.mpi-hd.mpg.de/personalhomes/bauke > -- Social Networking @ https://www.researchgate.net/profile/Heiko_Bauke ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org
