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Astrophotography (A non-scary introduction, hopefully) James Billings, March 2013

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Post on 26-Aug-2014




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These are the slides accompanying the 28th of March 2013 Cambridge Darkroom meetup: James Billings, a photographer with a penchant for all things starry, guided us through three different types of Astro Photography: - Wide field with just a camera - Planetary images with a webcam - Deep-sky images with a DSLR With plenty of examples included.


  • Astrophotography(A non-scary introduction, hopefully) James Billings, March 2013
  • Why bother?Why not just look through a telescope and appreciatethe beauty of the heavens? Why do you need tophotograph it?! Its all Hubbles fault
  • What Hubble sees
  • What you see
  • I dont have a telescope! OK, I bought a telescope. Using your DSLR Using a webcam
  • I dont have a telescope!No problem, as long as you have atripod and shutter release, exposuretimes are normally quite long... Some examples
  • Make the sky part of the picture16mm f/3.5, 30s @ISO-400
  • Use brighter night-sky objects18mm f/4.5, 8s @ISO-400
  • Zoom in!300mm f/11, 1/4s @ISO-200
  • Try capturing satellites30mm f/4, 25s @ISO-400
  • Rare events35mm f/6.3, 25s @ISO-400
  • Try to capture the Milky Way16mm f/3.5, 30s @ISO-1600
  • OK, I bought a telescope Using a DSLR on a telescopeChallenges: Light pollution The moon Long exposures Accuracy of mount Wind Pesky Satellites! 80s @ISO6400
  • Easy (ish) the moon1000mm f/1, 1/1000s @ISO-200
  • Harder - fainter objectsGalaxies Nebula Star Clusters
  • ProblemsPlanet earth rotates. This is NOT helpful. We use an Equatorial Mount to counteract the rotation of the earth. Even then, were limited: Alignment Worm error Stability
  • A single photograph1000mm f/1, 69s @ISO-1600 But we want this:
  • Traditional processingMore detail, but horrible noise. We need to increase signal > noise.Multiple exposures help as noise is random, subject is consistent.
  • Time for a demo
  • End resultAdjust luminance and RGB levels.Beautify in photoshop/lightroom/gimp etc.
  • Some more examples
  • What about the planets? Planets are small, details are tiny, so we need to increase our S/N even more (100s of shots) Our shiny DSLR is no use- the planet is too small in the image We need a smaller sensor = we use a webcam and record a movie!
  • Recorded videoLow resolution sample, up-scaled. Consumer cam (10-80)Avi courtesy Jim Prior ([email protected]/ )
  • Time for a demo
  • With an astro-specific cameraBetter quality CMOS sensor for less noise, ~240(.avi courtesy Keith Townsend:
  • Processing steps: Choose align-points Align, limit, stack Sharpen with wavelets Gamma/RGB adjustment
  • More examples. (mine )
  • The End jowlymonster JamesBillings jmbillingsRegistax (for planets): Sky Stacker (deepsky objects): (stack to make trails): (satellite timings): to Keith and Jim for the planet .avi files.