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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?...
What Hubble sees
What you see
• I don’t have a telescope!• OK, I bought a telescope.  – Using your DSLR  – Using a webcam
I don’t have a telescope!No problem, as long as you have atripod and shutter release, exposuretimes are normally quite lon...
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 satellites…30mm f/4, 25s @ISO-400
Rare events…35mm 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...
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. Eve...
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...
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)• O...
Recorded videoLow resolution sample, up-scaled. Consumer cam (£10-£80)Avi courtesy Jim Prior (http://www.flickr.com/photos...
Time for a demo…
With an astro-specific cameraBetter quality CMOS sensor for less noise, ~£240(.avi courtesy Keith Townsend: http://www.fli...
Processing steps:•   Choose align-points•   Align, limit, stack•   Sharpen with wavelets•   Gamma/RGB adjustment
More examples. (mine )
The End                                  jowlymonster                                  JamesBillings                      ...
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Cambridge Darkroom - Stars in our eyes by shooting stars in the sky at night

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These are the slides accompanying the 28th of March 2013 Cambridge Darkroom meetup: http://www.meetup.com/CambridgeDarkroom/events/106902682/

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.

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Cambridge Darkroom - Stars in our eyes by shooting stars in the sky at night

  1. 1. Astrophotography(A non-scary introduction, hopefully) James Billings, March 2013
  2. 2. Why bother?Why not just look through a telescope and appreciatethe beauty of the heavens? Why do you need tophotograph it?! It’s all Hubble’s fault…
  3. 3. What Hubble sees
  4. 4. What you see
  5. 5. • I don’t have a telescope!• OK, I bought a telescope. – Using your DSLR – Using a webcam
  6. 6. I don’t have a telescope!No problem, as long as you have atripod and shutter release, exposuretimes are normally quite long... Some examples…
  7. 7. Make the sky part of the picture16mm f/3.5, 30s @ISO-400
  8. 8. Use brighter night-sky objects18mm f/4.5, 8s @ISO-400
  9. 9. Zoom in!300mm f/11, 1/4s @ISO-200
  10. 10. Try capturing satellites…30mm f/4, 25s @ISO-400
  11. 11. Rare events…35mm f/6.3, 25s @ISO-400
  12. 12. Try to capture the Milky Way16mm f/3.5, 30s @ISO-1600
  13. 13. 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
  14. 14. Easy (ish) – the moon1000mm f/1, 1/1000s @ISO-200
  15. 15. Harder - fainter objectsGalaxies Nebula Star Clusters
  16. 16. ProblemsPlanet earth rotates. This is NOT helpful. We use an Equatorial Mount to counteract the rotation of the earth. Even then, we’re limited: • Alignment • Worm error • Stability
  17. 17. A single photograph1000mm f/1, 69s @ISO-1600 But we want this:
  18. 18. Traditional processingMore detail, but horrible noise. We need to increase signal > noise.Multiple exposures help as noise is random, subject is consistent.
  19. 19. Time for a demo…
  20. 20. End resultAdjust luminance and RGB levels.“Beautify” in photoshop/lightroom/gimp etc.
  21. 21. Some more examples…
  22. 22. 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!
  23. 23. Recorded videoLow resolution sample, up-scaled. Consumer cam (£10-£80)Avi courtesy Jim Prior (http://www.flickr.com/photos/70350201@N03/ )
  24. 24. Time for a demo…
  25. 25. With an astro-specific cameraBetter quality CMOS sensor for less noise, ~£240(.avi courtesy Keith Townsend: http://www.flickr.com/photos/keith-t/)
  26. 26. Processing steps:• Choose align-points• Align, limit, stack• Sharpen with wavelets• Gamma/RGB adjustment
  27. 27. More examples. (mine )
  28. 28. The End jowlymonster JamesBillings jmbillingsRegistax (for planets): http://www.astronomie.be/registax/Deep Sky Stacker (deepsky objects): http://deepskystacker.free.fr/english/index.htmlStartrails (stack to make trails): http://startrails.de/Heavens-above (satellite timings): http://www.heavens-above.com/Thanks to Keith and Jim for the planet .avi files.

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