Baldy45
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Posts posted by Baldy45
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Good Day,
Can someone supply me with an answer? Last night I took this image of M31 (Andromeda galaxy) using the following,
Camera - Pentax K70
Lens - Pentax DA* 300mm
Mount - Star Aventurer 2i
iso - 200
f - 4.8 using a 62mm step-down ring
Light subs - 60 x 90 seconds
Dark subs - 30 x 90 seconds
Bias subs - 30 x 1/6000 sec
Flat subs - 30 x 1/200 sec
As can be seen there is a tracking error, at the start of the session M31 was in the centre of the viewfinder. The final light sub had moved up and right in the frame.
Stacking in Siril rejected 31 light subs.
To find the Hour Angle of Polaris I use a Nautical Almanac, last night at 11pm (U.K.) the Hour Angle of Polaris was 4hrs 9mins.
If I had mis-read the clock face of the Star Adventurer and placed Polaris at 4hrs 20mins, would this cause the tracking to appear to be slow as shown by M31 moving up and right during the session.
Does this make sense?
Thanks for reading
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Hi all,
Found this site after being made redundant 2 years ago. After being a navigator at sea and using the heavens to find out were I was (lost), I am starting to learn how to photograph the stars. Look forward to constructive criticism of my efforts.
First attempt at Orion unguided,
Pentax K7,
55mm DA* Lens,
30 x 2 secs frames,
Siril,
Followed the tutorial on the Siril website.
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Tracking error
in Getting Started With Imaging
Posted
Thanks for the replies, this gives me something to think about.
Richard_ and vlaiv, I got the tracker in June and have been experimenting with different camera settings, this was the first time I have used an exposure length greater than 60 seconds.
So it looks like with my current set-up 60 secs is my limit.
AstroMuni, I think I know what you mean, here is how I work out the Hour Angle, this is for 11pm yesterday. Find attached how I workout the Hour Angle of Polaris.
Thank you for the kind comments, and will have another go tonight.
Hour Angle.pdf