I have already posted this here
, but didn't seem of much interest to the audience there. However I consider it something interesting so even if I may result boring I'll give it a new try on a discusion thread of its own.
It's all about HDR RAW fusion. All of us know that captured DR can be expanded by shooting more than once at different exposure values, and properly blending the information obtained from all those shots (in general highlights from the least exposed shots, and noiseless shadows from the most exposed ones).
Unluckily most programs performing this task (Photomatix, HDR in PS, Enfuse,...) do their proper RAW development and also do the tone mapping, so the user looses control over the process and cannot make use of his regular workflow tools.
What I tried to achieve is to fuse several RAW files, but obtaining another RAW file as output
. This resulting RAW file is noise free (as much as the source files allow for) and preserves the highlights, so looking at the information contained on it, it can be considered an HDR RAW file. But the new thing is that now the user can develop it in his own RAW developer or feed it into his preferred tone mapping software.
I.e., an optimum (maximum noise reduction and maximum sharpness preservation via non-progressive blending) mix is carried out over an arbitrary set of RAW files, putting the best information of each of them into a resulting RAW file (16-bit DNG) that summarizes all the useful information found in the original files. Now it is up to the user what to do next (develop it with his RAW developer, tone map it with Photomatix,...).
What do you think about the usefulness and applications of this RAW fusion?
The source RAW files and the resulting DNG are ready for download in the original article (see 'DOWNLOAD RAW FILES'): ZERO NOISE VIRTUAL RAW
The scene was captured through 2 exposures 4 stops apart and the resulting non demosaiced DNG is a real 16-bit RAW file, containing free of noise the ~12 f-stops of DR of the real scene. When comparing the resulting DNG to the original files in the extreme ends of the DR, we conclude none of them was capable on its own to capture all the DR, but the DNG is:
With proper RAW development adjustments we get straight from ACR this tone mapped HDR picture:
Some field must be missing or wrong in building the DNG file so I couldn't open it with DCRAW. Just try ACR which works fine with it.