This problem seems to still be in Mac OS X versions of 3.6.3. I tried the dmg downloaded from the KDE Education page, kstars-3.6.3-1637-macos-clang-x86_64.dmg downloaded from binary-factory.kde.org/job/KStars_Release_macos/ and the 3.6.4beta that Robert Lancaster posted a short while ago. All write FITS files that fail the Tester page in the same way as described in the original post on this topic. A lot of apps ignore it, but it seems AstroImageJ is more strict as it fails with an invalid header error. I'm using the SBIG CCD on MAC OS X 12.6.3

DanZ

Read More...