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Jupiter IR images from Skinakas

I was able to take a series of IR images from Skinakas telescope and Manos Kardasis did all the job with the processing. Here are the results:

Jupiter_20121007_MaraveliasKardasis

Synchronized optical and IR observations of Jupiter.
Manos’ comments: “It is interesting though that even in oneshot – low resolution images – some bright SSTB ovals are visible. Also NNTZ LRS (L2 308, B 40.7) is bright. Another big bright spot a little northern (at NNTBn?) is visible at L2 218, B 39.”

 

Manos’ comments: “There are some white spots visible on NEBs with the H21 filter. GRS and oval BA are bright in all sets (except CO).”

IRAF’s error message 502 and pixel value replacement

While running a data reduction of IR observations with IRAF, the ccdproc printed this error:

ERROR (502, “floating point invalid operation”)

which means that some values of the image used (the flat image in this case) are not suitable for the performing mathematical actions (like division with 0s). Moreover the IR ccds have many bad pixels so the best is to replace these values with standard ones in order to know exactly which areas are problematic.

In order to replace them the imcalc command (stsdas / toolbox / imgtools) can be used to replace these values, like:
imcalc master_flat_temp.fits output="master_flat.fits" equals="if (im1.le.0.0) then -9.0 else im1"
if we want for example to replace all values lower or equal (le) to 0.0 with -9.0.