Hi all, you are all right: what I am doing is not far from HDR (or at least from the previous steps any HDR soft performs prior to the tone mapping stage), or to any blending technique of 2 or more images into one as CS3 can do. In fact I posted this method in the Spanish forum calling it "soft HDR". The result of combining different images will, among others, be always an increase in dynamic range through overall signal to noise ratio improvement.
What I try to show you (no commercial interest as I don't sell my little programs
) is a simple soft that is focused on providing:
- Minimum noise (none of the techniques above can improve it; the more can be expected is to match results).
- Maximum texture detail in deep shadows (there is no blending in fact, just pixel selection which is optimum).
- Natural dynamic range expansion in the shadows end (not tone mapping or so steps applied than transfigure our picture's appearance and give it an unreal appearance).
The goal is provide the cleanest possible image to the user with just a click keeping the original image parameters (bright, contrast and tones). It is now up to him to choose the way how to use it; it could even be used as a free of noise input to any HDR soft (Photomatix for instance can deal with one single RAW, or you can use two versions of it for the PS HDR module), or most commonly be processed using zones without surprises when pumping up the darkest areas.
A friend of mine is modifying DCRAW's C source code to perform all these operations, not only in linear as I do, but over the RAW file itself prior to Bayer demosaicing, white balance or any scaling (in fact we are having some trouble with the black point offset most cameras keep in their RAW files that must be substracted before being able to consider a linear behaviour of the sensor, which is not strictly linear due to this offset).
And if he manages, I'll try to convince him to pursue a 16-bit DNG RAW file as an ouptput. That would be simply great, can you imagine? put a bunch of RAW files, with different arbitrary exposition, into a 16-bit RAW file free of noise ready for developing on your favourite RAW developer.
But I have a feeling that recreating the DNG RAW format is not a joke so perhaps we must be happy with just putting our fingers into the image before the developing process.