Star Shape Query

[salas]

Hi All,

I've only just got out for the second time with my WO GT81 and would like to know if the star shape on brighter stars I am seeing is normal? I've attached a 10 second exposure of Vega, I was using the WO focal reducer flattener with my Canon DSLR, although without the flattener the effect is the same. I could not see any moisture build up on the scope lens.

I've zoomed right in to make it easier to see. Is the effect I am seeing a result of Vega being blown out compared with the surrounding stars?

Any thoughts would be appreciated.

Thanks,

Steve 

[D4N]

What you are seeing is diffraction spikes caused by obstructions in the light path. They are more prominent the brighter the star is.

You may want to take a look at a similar post from a few days ago where someone with the exact same scope as you also has this problem.

http://stargazerslounge.com/index.php?/topic/255328-Focus-and-Diffraction-Spikes

/Dan

Sent from my iPad using Tapatalk

[salas]

Thanks Dan will have a read.

Steve

[Galaxyfaraway]

I just posted the same question in another thread. I have the same scope and see the very similar shapes (images attached). I wonder if it is a characteristic of this refractor? I also don't know if it is a flaw or not. Please let us know how you get on (fixing or returning it etc) as I am not sure what to do myself.

I don't think it would bother me if the star itself was round and then had diffractions but the spikes seem to cut into the star which is annoying,