You better read the responses you get here more carefully. It is not the first time you participate a discussion about base curve. I will try to give you a short summary.
The camera sensor reacts almost linear to exposure. Human perception does not, it can be approximated by some exponential function, you sure have read the term "gamma function". The conversion between those worlds has to be done by applying the gamma correction to the image. If you take a look at the gamma function for a gamma value of something about 2, you see the darker input values are stretched into the brightness, which is what you observe if you turn off the base curve. Until the applied base curve contains some offset for the darkest or brightest part, the full histogram will be used even if you disable the base curve. Reminder: The base curve tries to approximate the look of out of camera JPEGs. The camera software does not only apply a simple gamma correction but also some additional postprocessing which creates the special "$vendor_name"-look. Regards, Markus PS: The histogram your camera shows is derived from the internally generated (embedded) JPEG which has some kind of base curve applied like i explained above ... Am 04.08.2013 22:10, schrieb Marie-Noëlle Augendre: > I said a few days ago that the basic curve gives lobster skin to people. > I'm now working on a whole batch of landscapes photographies, and for them > too the colors are very wrong, with greens and yellows completely > oversaturated. > In both cases, I have to deactivate the basic curve in order to start > working on a not too bad picture. When doing so, in both cases, the > histogram comes way too much on the left, and I need to adjust the > exposition for every picture... to the point I'm wondering whether the > basic curve could be supposed to fix a wrong exposition treatment when > demosaicing. > > At shooting time, I take care of the exposition so the histogram is on the > right side, sometimes blowing up the higlights. I definitely don't > understand why/how I get an underexposed picture when I import it in > Darktable and deactivate the basic curve. > > Marie-Noëlle > > > > ------------------------------------------------------------------------------ > Get your SQL database under version control now! > Version control is standard for application code, but databases havent > caught up. So what steps can you take to put your SQL databases under > version control? Why should you start doing it? Read more to find out. > http://pubads.g.doubleclick.net/gampad/clk?id=49501711&iu=/4140/ostg.clktrk > > > > _______________________________________________ > Darktable-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/darktable-users > ------------------------------------------------------------------------------ Get your SQL database under version control now! Version control is standard for application code, but databases havent caught up. So what steps can you take to put your SQL databases under version control? Why should you start doing it? Read more to find out. http://pubads.g.doubleclick.net/gampad/clk?id=49501711&iu=/4140/ostg.clktrk _______________________________________________ Darktable-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/darktable-users
