December 06, 2016, 11:05:19 AM

Author Topic: Deep Sky Astrophotography  (Read 159224 times)

Don Haines

  • Canon EF 600mm f/4L IS II
  • **********
  • Posts: 5442
  • posting cat pictures on the internet since 1986
Re: Deep Sky Astrophotography
« Reply #570 on: December 02, 2016, 06:55:38 AM »
My question is about filters.

My home is far enough out of town that the night sky is visible, but there is still some light pollution. Is there a filter (preferably 77mm) that I can use to help cope with the light pollution?

Any LP filtration will likely just diminish the quality of your results. There is always LP. In fact, airglow, natural light pollution from the ionizing layers of our atmosphere, imposes the upper limit on sky darkness at around 22-22.5mag/sq". Once you get out about half way into a yellow bortle zone or darker (you can look up maps for the scale), then LP filtration really hurts more than it helps, as it tends to decimate color fidelity.

If you are in an orange, red, or white zone, an IDAS LPS-D1 can help, although I don't think you'll ever find one in 77mm size. You might have to step down to a smaller one.
I'm in a light green area.... I guess that means just use the bare lens.... Thanks.
The best camera is the one in your hands

canon rumors FORUM

Re: Deep Sky Astrophotography
« Reply #570 on: December 02, 2016, 06:55:38 AM »

chrysoberyl

  • Canon 6D
  • *****
  • Posts: 335
  • 6D
Re: Deep Sky Astrophotography
« Reply #571 on: December 02, 2016, 11:07:15 AM »
My first attempt at Orion with the 80D. Sometimes my exposure is slightly too long and there is a bit of trailing and stars become oval. In this case movement was from bottom right to top left. What is a good method for deconvolution?

Nice first shot!  No tracker?  I have an 80D and a 70-200, but I was convinced I would have to use a tracker.

If you didn't use a tracker, I may have to consider my 80D + the Samyang 85mm 1.2 (when it becomes available, if coma is low, etc., etc.) for intermediate sky astro.
6D, 80D, Zeiss Milvus 100mm Makro, Sigma 180mm/2.8 macro, Canon 100mm macro, Canon 24mm/1.4, Sigma 35/1.4, Tokina 16-28, Canon 1.4X III TC, Canon 2X III TC.

StudentOfLight

  • 5DSR
  • *******
  • Posts: 1323
  • I'm on a life-long journey of self-discovery
Re: Deep Sky Astrophotography
« Reply #572 on: December 03, 2016, 11:57:57 AM »
My first attempt at Orion with the 80D. Sometimes my exposure is slightly too long and there is a bit of trailing and stars become oval. In this case movement was from bottom right to top left. What is a good method for deconvolution?

Nice first shot!  No tracker?  I have an 80D and a 70-200, but I was convinced I would have to use a tracker.

If you didn't use a tracker, I may have to consider my 80D + the Samyang 85mm 1.2 (when it becomes available, if coma is low, etc., etc.) for intermediate sky astro.
If you have a tracker then you don't have to shoot hundreds of exposures (so less wear and tear) and less processing time. Also when you track you will capture more faint details than possible with multiple short exposures. What happens with multiple short exposures is that the faint subjects will not supply enough light to raise them above the noise floor, so they will be averaged out in the stacking process. At least that is how I understand things.

If you can afford (or have the ingenuity and time to build) a tracking system then it will be incredibly beneficial.
« Last Edit: December 03, 2016, 12:17:07 PM by StudentOfLight »
Fantasy Gear:
TS-E: 45mm f/2.8 L,  EF: 40mm f/0.8,  100mm f/1.4,  18-28mm f/2, 28-85mm f/2, 
EF with 1.4xInt: 100-300mm f/4 ,  500mm f/5.6 L

canon rumors FORUM

Re: Deep Sky Astrophotography
« Reply #572 on: December 03, 2016, 11:57:57 AM »