Issue for ST-8300C image

[jacksonlu]

Hello all,

I am a new user of PI. Got a trouble when using debayer images that I took by SBIG ST-8300C.
Images were took by ST-8300C via MaximDL camera control. But seems debayer results with wrong
colors from PI. I tried many way and found need to rotating images to Clockwise 90 degree then
can see the right color. Anyone can point out what step I went wrong ? thanks in advance.

Clear skies

Lu

[pfile]

could be the fits reader direction (up-bottom or bottom-up). are your images in fits format?

[Philip de Louraille]

Can't be sure but debayer has to be step #1 prior to any cropping or rotation *whatsoever*.

[jcajolet]

Hello,
I have the same problem with the ST-8300c, I tried everything in PI, the closest pattern is th GRBG in VNG. My work flow is: I take pictures with CCDOps  and save them in .FITS format, calibrate pictures (in PI) with Bias, Dark and Flat, debayer. The result is closed but not like doing a debayer with CCDOps. The red that's going out is washed closest to the pink without depth. I use CLS CCD filter that I was also using with an ATIK 314L+ without any problems in PI. I suspect that the bayer matrix of ST-8300c is very different than the others.
Would be nice to get an answer about this fact.
Thanks

[jcajolet]

Hello,
by trying different alternatives I found a solution: first as 'pfile' said the .fit must be "up-buttom" and the debayer must be at BGGR VNG or Bilinear depending of the result. Colors are quite the same as CCDOps (for the debayer). I haven't tried to take pictures with MaximDL but I suspect that this receipie will work also with it.

[jacksonlu]

With the same fit file on MaximDL or CCDOPS, no problem for the colors. Even in DSS , I only need to set BGGR debayer but
PI can't debayer a right color even set to BGGR. I need to set rotation to clockwise 90 and use RGGB...

It is very incovnience when large numbers of fit to processing on PI...

[Carlos Milovic]

Try changing the FITS format preferences, and set the origin of the coordinates to be the top left corner.

[jacksonlu]

Hi Carlos,

Thanks for sharing this info. I did not find this setting...on which menu item?

Here is the lastest FIT header,image took on yesterday.

SIMPLE     = T                                                 
BITPIX     = 16 /8 unsigned int, 16 & 32 int, -32 & -64 real     
NAXIS      = 2 /number of axes                                 
NAXIS1     = 3352 /fastest changing axis                           
NAXIS2     = 2532 /next to fastest changing axis                   
BSCALE     = 1.0000000000000000 /physical = BZERO + BSCALE*array_value           
BZERO      = 32768.000000000000 /physical = BZERO + BSCALE*array_value           
DATE-OBS   = '2012-06-25T18:57:17' /YYYY-MM-DDThh:mm:ss observation start, UT     
EXPTIME    = 600.00000000000000 /Exposure time in seconds                       
EXPOSURE   = 600.00000000000000 /Exposure time in seconds                       
XPIXSZ     = 5.4000000000000004 /Pixel Width in microns (after binning)         
YPIXSZ     = 5.4000000000000004 /Pixel Height in microns (after binning)         
XBINNING   = 1 /Binning factor in width                         
YBINNING   = 1 /Binning factor in height                       
XORGSUBF   = 0 /Subframe X position in binned pixels           
YORGSUBF   = 0 /Subframe Y position in binned pixels           
READOUTM   = 'Raw     ' /          Readout mode of image                           
IMAGETYP   = 'Light Frame' /       Type of image                                   
OBJECT     = 'NGC7293 '                                                           
OBJCTRA    = '22 29 21' /          Nominal Right Ascension of center of image     
OBJCTDEC   = '-20 49 44' /         Nominal Declination of center of image         
OBJCTHA    = '  1.4996' /          Nominal hour angle of center of image           
JD         = 2456104.2897800924 /Julian Date at start of exposure               
JD-HELIO   = 2456104.2964057978 /Heliocentric Julian Date at exposure midpoint   
TRAKTIME   = 4.0000000000000000 /Exposure time used for autoguiding             
FOCALLEN   = 0.00000000000000000 /Focal length of telescope in mm                 
APTDIA     = 0.00000000000000000 /Aperture diameter of telescope in mm           
APTAREA    = 0.00000000000000000 /Aperture area of telescope in mm^2             
EGAIN      = 0.37000000476837158 /Electronic gain in e-/ADU                       
SWCREATE   = 'MaxIm DL Version 5.18 121002 159AV' /Name of software that created   
the      image                                                             
SBSTDVER   = 'SBFITSEXT Version 1.0' /Version of SBFITSEXT standard in effect     
TELESCOP   = '        ' /          telescope used to acquire this image           
INSTRUME   = 'SBIG ST-8300 Color CCD Camera'                                       
OBSERVER   = '        '                                                           
NOTES      = '        '                                                           
FLIPSTAT   = '        '                                                           
SWOWNER    = 'YEN LING LU' /       Licensed owner of software                     
INPUTFMT   = 'FITS    ' /          Format of file from which image was read       

[Juan Conejero]

Hi Lu,

- Open the Format Explorer window.

- Double click the FITS item on the left column.

- On the FITS Format Preferences dialog, Miscellaneous Options section, select Coordinate origin = Upper left corner.

- Click OK

Now all your FITS files will be loaded with the correct orientation by default, and you won't have problems to de-Bayer them anymore.

[jacksonlu]

 

Thanks Juan. It works.