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Hello,I am currently working on the rear camera sensor of an iPhone and I have noticed a strange behavior with exposure settings and raw RGB data (in DNG). The same problem occurs with both iPhone 6S and iPhone 7 on iOS 10.0.1 and Xcode 8.I made two experiments :- In the first, I set manual shutter speed and manual ISO (with setExposureModeCustomWithDuration:ISO: ) and sometimes the luminosity of the picture changes (which should not occur as exposure parameters are fixed)- In the second, I want to check the linearity of raw RGB according to ISO (exposure duration is blocked). At the begining everything is almost perfectly linear but when I increase ISO to a certain value, raw RGB do not change (though they are far from being saturated) while in photos the luminous shifts are present as expected. I have found out that this information is stored in the DNG EXIF data in the Baseline Exposure (BLE) tag. When I correct those RGB with this exposure shift (using 2^BLE, the formula that I believe to be correct), I lose the linearity between RGB and ISO, which is a big problem for me. In addition to this, the tone curve in DNG file is perfectly linear which I believe is wrong in the latter case.I believe that the two problems are correlated and that in both cases the camera does a hidden exposure compensation. Is there a way to block this behavior and if not, will it be possible to know what is happening in the sensor?Best regards,