Well I was trying to figure out what is wrong with the camera.
Usually these conversion tables (basically firmware for DAC) are part of firmware (with every other manufacturer except Sigma). So once you updated firmware it will wipe out everything (image processing wise).
Then something strange caught my attention. I am converting cameras for over 15 years and was customizing firmware on some of them as well. I do not remember a single case when camera would allow users to openly to re-update already up to date firmware. Sigma does!
For example. In Oly cameras from service menu you can see error codes. There are NO direct prompt on screen to delete those codes but you CAN DELETE error codes and reset camera state!
On SD Q You can update 1.08 to 1.08 again and again. So question was why did they leave this possibility there for users?
I read that some users mentioned cameras purchased at different time had different colors (per say). So it must be some sort of signal processing algorithms update, but it was not the case when users updated firmware themselves.
On Sigma website they were describing bags such as camera does not shut off when you switch it off as "phenomena". Not a bag but phenomena!
That meant there must be another way to get to wipe out old/damaged firmware for DAC. I was thinking to send camera to Sigma to see if they will fix it or they will replace it. And in once of their PDF I saw mentioning of "image processing file" to improve sharpness. Well knowing Sigma I was pretty sure it is not for sharpness. I SD Q I had briefly about year ago was pretty sharp out of box! It is something else. Well may be sharpness as well but not only the sharpness issue. And why sharpness processing algorithm should not be part of firmware update? Firmware update added DNG so sharpness has nothing to do with it.
I updated that file. It worked.
The question is: How it got corrupted? Will it repeat again?