Nona - hdr in hdr out dynamic range loss

[psychospiller]

Hi,

I am trying to use nona via commandline to process a rectilinear 2:1
spherical image in either .hdr of .tff 32bits FLOAT and extract cubic
faces in either .hdr or .tiff 32bits FLOAT. I can create the cubic
files but the dynamic range seems to have shifted or reduced somewhat,
by this i mean when adjusting the exposure in a viewer the darker
areas of the image have lost their range and become grey compared to
the source file that has more range all the way down to the all black
level. Is there a setting in nona to maintain the dynamic range of
the source image?

[T. Modes]

Check the exposure settings: both, the ev value of the input image and
the output exposure value (on the fast preview) should be the same
value. Try best with both values set to zero.