Hi!

That looks like an interesting spectroscope, compact design, if I get it right. I use the Lowspec for low resolution spectra, which is what I do most, and I like the compact design of that too - although it is somewhat less easy to focus the guidecam as compared to the StarEx. I use the StarEx for high resolution spectra, just nu feeling confident enough with it to just use it. Neither are remotely controlled - that would be nice. I'm looking into how to make calibration lamp remotely controlled. And the SpecINTI allows "lateral mode" calibration, that would be really handy - but then the lamp must be software controlled. I use a CCD for my Lowspec, an Atik 314L+, and a CMOS for the StarEx, a QHY183m. I'm also not sure about the gain values for the CMOS. For the moment, I use gain 10 to get as large full well as posslble (for bright targets) and to only have one set of darks and flats. I can imagine having higher gain would be good for fainter targets though. Unfortunately, QHY and ZWO use different logics for their gain values, as I understand it, so Christian Buil's recommendations based on his ASI183 are not useable for me.

And back to the header issues: Last night, spectrum of R Leo using my SM with KStars 3.6.4, I get these headers from the StarEx:

SIMPLE = T / file does conform to FITS standard
BITPIX = 16 / number of bits per data pixel
NAXIS = 2 / number of data axes
NAXIS1 = 5544 / length of data axis 1
NAXIS2 = 1000 / length of data axis 2
EXTEND = T / FITS dataset may contain extensions
COMMENT FITS (Flexible Image Transport System) format is defined in 'Astronomy
COMMENT and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H
BZERO = 32768 / offset data range to that of unsigned short
BSCALE = 1 / default scaling factor
ROWORDER= 'TOP-DOWN' / Row Order
INSTRUME= 'QHY CCD QHY183M-9b51164' / CCD Name
TELESCOP= 'Celestron NexStar' / Telescope name
EXPTIME = 3.000000E+02 / Total Exposure Time (s)
CCD-TEMP= -1.000E+01 / CCD Temperature (Celsius)
PIXSIZE1= 2.400000E+00 / Pixel Size 1 (microns)
PIXSIZE2= 2.400000E+00 / Pixel Size 2 (microns)
XBINNING= 1 / Binning factor in width
YBINNING= 1 / Binning factor in height
XPIXSZ = 2.400000E+00 / X binned pixel size in microns
YPIXSZ = 2.400000E+00 / Y binned pixel size in microns
FRAME = 'Light ' / Frame Type
IMAGETYP= 'Light Frame' / Frame Type
FOCALLEN= 2.000E+03 / Focal Length (mm)
APTDIA = 2.790E+02 / Telescope diameter (mm)
FOCUSPOS= 700 / Focus position in steps
FOCUSTEM= 2.000E+01 / Focuser temperature in degrees C
SCALE = 2.475600E-01 / arcsecs per pixel
SITELAT = 5.554806E+01 / Latitude of the imaging site in degrees
SITELONG= 1.336472E+01 / Longitude of the imaging site in degrees
AIRMASS = 1.483571E+00 / Airmass
OBJCTAZ = 2.111180E+02 / Azimuth of center of image in Degrees
OBJCTALT= 4.233853E+01 / Altitude of center of image in Degrees
OBJCTRA = ' 9 46 10.43' / Object J2000 RA in Hours
OBJCTDEC= '11 29 40.85' / Object J2000 DEC in Degrees
RA = 1.465435E+02 / Object J2000 RA in Degrees
DEC = 1.149468E+01 / Object J2000 DEC in Degrees
PIERSIDE= 'EAST ' / East, looking West
EQUINOX = 2000 / Equinox
DATE-OBS= '2023-04-23T20:14:13.101' / UTC start date of observation
COMMENT Generated by INDI
GAIN = 1.000E+01 / Gain
OFFSET = 2.000E+01 / Offset
OBJECT = 'R Leo ' / Object
END

So information about where it is pointing is obviously there, but not the keywords. An hour later, doing photometry, there are some 10 lines more, including the CRVAL. I guess this is a snooping issue.

Magnus

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