auto brightness calculates image histogram, than adjust (increase) values to fit full 16-bit range (with 1% of pixels at saturation with default auto_bright_thr). So, if you use linear exposure correction (w/o highlights compression), than your changes will be ruined (indeed), because brightness is adjusted to use full data range.
Do not know what 'color adjustment' you use,because no such mechanics exists in dcraw_process() options (excluding white balance).
Without auto-bright, 8-bit images use only 0..255 range (to be correct,it may be more if white balance is used). This is 8 stop below full range (0..65535), so resulting image will look 'near black' (not completely black).
These results are expected (more or less).
auto brightness calculates image histogram, than adjust (increase) values to fit full 16-bit range (with 1% of pixels at saturation with default auto_bright_thr). So, if you use linear exposure correction (w/o highlights compression), than your changes will be ruined (indeed), because brightness is adjusted to use full data range.
Do not know what 'color adjustment' you use,because no such mechanics exists in dcraw_process() options (excluding white balance).
Without auto-bright, 8-bit images use only 0..255 range (to be correct,it may be more if white balance is used). This is 8 stop below full range (0..65535), so resulting image will look 'near black' (not completely black).