I have been using a Fuji X100S camera for a few months now and have found some confusion on forums as to how Fuji handles their Dynamic Range (DR%) adjustments, particularly with regard to raw output. I thought I would post a synopsis of my personal findings for those interested now that the Fuji X-trans sensor cameras are supported on dt.
Fujifilm, despite providing raw image data, appear to be intent on making an effort to seriously improve and encourage photographers to use jpg camera output. Their camera controls allow for both significant pre and post shot adjustments to the tone curve, the color model, sharpening, noise reduction and most importantly the image's dynamic range; working from the raw into the jpg format. Some early tests using jpg output did confirm that the dynamic range, using the DR% settings, is greatly improved .... my question was, how can I utilize this while shooting raw? Yesterday I made a test, photographing a test card with the camera fixed on a tripod, I photographed the card with aperture priority setting with the camera retaining both raw+jpg. I made 3 exposures as follows: 1.) ISO.200 @ DR.100%, 2.) [email protected]% and 3.)[email protected]% The files were opened in dt and the 3 jpgs looked identical with all of the histograms totally matching. The 3 raw files were opened and striped of all processing except the demosaic, the higher ISO images all indicated underexposure and when I added 1 EV to the ISO.400, and 2 EV to the ISO 800 all of the raw images were also identical in all histogram bands. It appears that when using the DR settings, all that Fuji is doing is underexposing by 1 or 2 EV in order to 'protect' any highlights and then 'overdevelop' (or expand the range) accordingly. Fuji cameras show the end result of all of the various settings in their display systems, as if one was shooting jpg alone, so this alleviates problems that could occur with metering when shooting raw. Expanding the range in dt simply involves a change in the EV within the exposure model .... all really quite simple. In real world tests I have used this approach in some fairly extreme night scenes with subjects containing both bare bulbs and deep shadows, it works really well .... and ..... without encountering an apparent noise gain ... all quite satisfactory. I have been working with Dan's dt X-trans branch for some time now, it has been rock-solid during development and I am very pleased that it now gets merged into dts' main stream. David ------------------------------------------------------------------------------ Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck Code Sight - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds _______________________________________________ Darktable-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/darktable-users
