Diffraction spike weirdness.

[thing]

Was going to thrash M45 last night but the clouds rolled in after I had 10 minutes worth of subs. Anyway, I processed what I had and I noticed a sort of 'bent' diffraction spike effect on the left and bottom spike. I wondered if the secondary vanes might be a bit twisted?

(click to enlarge)

[Psychobilly]

hmmm def something up there Dave

[Doc]

Yeah I would say vanes are slightly not centered.

[iancandler]

It looks like the vanes moved slightly between exposures as it appears there isnt so much a bend or kink but two separate image of the vane.

[Doc]

How did this happen?

[thing]

It looks like the vanes moved slightly between exposures as it appears there isnt so much a bend or kink but two separate image of the vane.

I checked single images Ian and it's on those too. I'll check the vanes tomorrow, see if they are a bit out of alignment. Thanks for the replies chaps.

[Kaptain Klevtsov]

This happens when the opposite vanes aren't in a straight line. You should be able to check by putting a 6" rule on the back of the secondary holder. I think the chrome buttons on the outside of the 'scope are used to adjust this alignment, but you'll need a recollimate after.

Kaptain Klevtsov

[Kaptain Klevtsov]

Had a play in PS, there's rather a lot of nebulosity yet to come out of that Dave. All it needs is some levels and curves, and seeing as you have the raw data, you ought to get some really good stuff happening. Great catch.

Kaptain Klevtsov