Quote:
Originally Posted by Mickoid
I got a similar effect on this one using a Tamron f 8 mirror lens the other night. Don't know what causes it, maybe focus?
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Mickoid, you seem to have halos on some other stars too (although smaller and fainter).
I actually googled Tamron f8 mirror lens because I had no idea what that is. I've never seen anything like it! That's a cool bit of kit!
I did a bit of reading about it and saw this
review.
Interestingly reading that review, they mention funny looking Bokeh, and when I saw their image it looks very much like your Halo.
Perhaps your focus wasn't close enough?
Just for reference I used a Bahtinov mask and my rings persisted over multiple nights, each night had a few focus check every hour or so.
Quote:
Originally Posted by RyanJones
Different star, same halo .....
I just thought I just had bad subs but mine is identical to yours.
odd....
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Just curious RyanJones what telescope and camera did you use to capture your images? It seems your Halo is eccentric like mine too.
I also had halos coming for the star yours is, it just was further away from the nebula then the star causing most of my problems and not as bright so it wasn't my main concern.
So far the list of things I think it could be causing or contributing (for me anyway) is:
- Incorrect back-focus causing field to not be flat, making the star bloat weird - The fact moving the star closer to center reduces the halo makes this my best guess as the field is flatter towards the middle. The less flat the field the worse it gets?
- Collimation not good enough?
- Internal reflections (very doubtful)
- It's just really damn bright and the 8SE maybe doesn't have mirror coatings that can handle it well???