Very good. I have tried it myself but tracking was very poor. Also the temperature is about 10°C so noise is much more visible. Will give it another try. Clear skies!
Thank you! Keep on! I had many and still have bad sessions. Two weeks ago I shooted the Cocoon Galaxy… The stacked result disappointed me. Out of focus and overall very bad quality (weather was not perfect that evening)… So, one more evening was lost… CS
I see you have used only 120 sec subs for this one. I assume also because the object was lower on the sky and tracking is worse there If I assume correct. BR
Yes, correct. Objects near to Polaris (60-80° declination) have a much shorter orbit on the sky than objects near to 0° declination. And on a shorter orbit tracking errors are less visible.
I use the following exp.times with the 400mm lens (guided!):
0°-40° declination: 120s exp.
40°-50° dec.: 150s
50°-60° dec.: 180s
60°-70° dec.: 240s
Until now this works perfect for me.
Clear Skies
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5 comments
Very good. I have tried it myself but tracking was very poor. Also the temperature is about 10°C so noise is much more visible. Will give it another try. Clear skies!
Thank you! Keep on! I had many and still have bad sessions. Two weeks ago I shooted the Cocoon Galaxy… The stacked result disappointed me. Out of focus and overall very bad quality (weather was not perfect that evening)… So, one more evening was lost… CS
I see you have used only 120 sec subs for this one. I assume also because the object was lower on the sky and tracking is worse there If I assume correct. BR
Yes, correct. Objects near to Polaris (60-80° declination) have a much shorter orbit on the sky than objects near to 0° declination. And on a shorter orbit tracking errors are less visible.
I use the following exp.times with the 400mm lens (guided!):
0°-40° declination: 120s exp.
40°-50° dec.: 150s
50°-60° dec.: 180s
60°-70° dec.: 240s
Until now this works perfect for me.
Clear Skies
Thanks for this information!