Isis processing issues
Posted: Wed Mar 22, 2017 8:08 am
While I was processing the instrument response star for my 3C 273 data, I found I was unable to
get Isis to display spectra data below 3950 and above 7595 angstroms. My profile of SAO119503 looked
full of interesting absorptions/emission lines from 3750-8300A (btw I know some of the IR is 2nd order);see:
https://goo.gl/photos/5nPu1WTjrowqZeJj7
---NOTE: I darkened the "unobtainable" spectral regions grey in PS, not an Isis graphic function!-------
But when processing this star for Instrument response, my data (after flats) was "too noisie" to get anything
below or above the wavelength limits (3950 & 7595) mentioned above.
Are my flats too under or over exposed? See the process 3C 273 (15x180sec 2x2 binned images) spectra:
https://goo.gl/photos/DyYQkUMpPNiQ6Lk19
I did as Christian recommended and made the flats about 55K ADUs as read in MaximDL's Medium stretch window.
Should I exposure them more or is it another issue?
I hate getting good data that I cant make ISIS reduce into useful spectral continuum.
James
get Isis to display spectra data below 3950 and above 7595 angstroms. My profile of SAO119503 looked
full of interesting absorptions/emission lines from 3750-8300A (btw I know some of the IR is 2nd order);see:
https://goo.gl/photos/5nPu1WTjrowqZeJj7
---NOTE: I darkened the "unobtainable" spectral regions grey in PS, not an Isis graphic function!-------
But when processing this star for Instrument response, my data (after flats) was "too noisie" to get anything
below or above the wavelength limits (3950 & 7595) mentioned above.
Are my flats too under or over exposed? See the process 3C 273 (15x180sec 2x2 binned images) spectra:
https://goo.gl/photos/DyYQkUMpPNiQ6Lk19
I did as Christian recommended and made the flats about 55K ADUs as read in MaximDL's Medium stretch window.
Should I exposure them more or is it another issue?
I hate getting good data that I cant make ISIS reduce into useful spectral continuum.
James