<<PREVIOUS - HOME - CONTENTS - NEXT>>
SPECTROSCOPY INDEX -

Pleiades M45 Stars Spectra

Image Information

• The stars are at spectral order zero and the horizontal lines on each side of the star are the spectral orders plus and minus one.
• The spectra at the blazed spectral order plus one is to the right of the star.
• The blazed spectral order plus one is brighter than the spectral order minus one.
• The very bright stars create dim spectral orders plus and minus two which start where spectral orders plus and minus one end.
• The dark gaps on the left side of the blazed spectral order plus one spectral lines are mostly caused by the hydrogen Balmer series H-delta (very dim), H-gamma and H-beta (most visible) absorption lines going from the left to right.
• Field of view of full image: 77 arcminutes wide x 53 arcminutes high
• Image scale of 2.12 arcsec/pix.
• Top image is full size
• North is bottom and west is left
  
• Exposure: 1 image x 7 seconds per image
• Darks: 45 x 7 seconds per dark frame
• Flats: 32 x 12 seconds per flat frame
• Darks for Flats: 64 x 12 seconds per dark frame
• CCD-TEMP: -25°C
• Tracking, no guided
• Information: Measure Signal to Noise of the background with no stars
  • Background average 39.637/background Std Dev 1.523 = Signal to Noise 26.0

Observing Information

• OBS-Location: Camas, WA USA, 16.6 miles East-North-East from the center of Portland, OR
• Image taken through the Vancouver, WA USA sky glow
• DATE-Local = October 10, 2009 at 1:53 am PDT

Imaging Equipment

• Rainbow Optics Visual, Photo and CCD Star Spectroscope mounted in the QSI 532ws-M1 filter wheel
• QSI 532ws-M1 CCD Camera, Tele Vue NP127is Refractor and Astro-Physics 1200GTO German Equatorial Mount

Imaging Processing

• AIP4WIN V2.2 Series Analysis each image
• Diffraction Limited MaxIm DL V5.07
  • Create master dark with SD Mask combine
  • Create master flat dark with SD Mask combine
  • Create master flat with SD Mask combine
  • Calibrate image with master dark and master flat
  • Save as FIT
  • Screen Stretch to see background noise
  • Save as 8-bit TIFF for Photoshop, Stretch, Linear Only, Input Range Screen Stretch, Output Range 8-bit
• Adobe Photoshop CS3 10.0.1
  • Label stars
  • Save as JPG for webpage

Monitor Test Pattern

The following test pattern is to help you adjust your monitor to best view the CCD astro images. The test pattern is used for adjusting monitor brightness, and contrast. Adjust monitor brightness and contrast to see all 16 gray scale levels. The most important adjustment when viewing astro images is to see the differences in all of the black bands.

© 1998-2010 David Haworth