====VATT Spectrograph====
  * This optical region spectrograph has AR coated refractive optics, with a beam size at its camera of 125 mm, giving …
  * slit length: 30 arcsec
  * wavelength range: 360 - 950 nm
  * spectral coverage: 100 nm at 0.1 nm resolution
  * spectral resolutions: 0.1, 0.2, and 0.4 nm with 1 arcsec wide slit
  * detector: back illuminated, low noise CCD STA0520A, with very nice cosmetics.

  STA0520A CCD
  2688×512 pixels, 15 microns
  ITL Serial Number 8228
  Detector operating temperature -110C
  Gain = 1.3 e/DN with setting 10
  Gain = 2.6 e/DN with setting 5
  For both gains the full well is ADC limited (65k DN), so this is 85,000 or 170,000 electrons.
  Noise is 3.4 electrons (3.2 in overscan region)

  * [[VATT:vatt-vattspec_efficiency|efficiency]]: determined by Mark Wagner for telescope plus spectrograph
  * further details are under the {{ :vatt:vattspec-instructions.pdf|General Instructions}} for use of the VATT Spectrograph.
  * bandpass [[vatt:filters|filters]] available: S8612 (red blocking); GG-400, GG-475, OG-550 (cut-offs to the blue in nm).

===Documentation===
  * {{ :vatt:vattspec-instructions.pdf |General Instructions}}
  * {{ :vatt:vattspec-guider-notes.pdf |Instructions on Guiding}}


===Maintenance===
  * Argon Calibration Lamp was replaced on 4/26/2013.
  * Note: There is some concern the lamps are burning out faster than they should.
   
===Chip QE Curve===
{{:vatt:qe_vattspec.png|}}