At last, my elongated stars have gone!!

[swag72]

I just had to write this thread, as there have been so many people that have helped me in the past few months with my continual battle against elongated stars.

Thanks to Cat's thread about his Super Newt, I decided to play with the spacing with my Atik. After a couple of nights, I finally can say I have beaten the demon and my 15 mins guiding last night gave me roundness across the frame.

I don't know how much my final tweak of the focuser worked - Tightened it up with a counterweight on the top so that it couldn't move too far out of kilter as it was tightened up! Checking again that my reducer was seated nice and flat in the focuser - But it all seems to have come together in beautiful loveliness!!

Now I am of course cheating in a sense as my 314L chip is tiny compared to many!! But the DSLR is not going any where near the 120ED, so I can not get all bitter and dissapointed again!! I am sure that the corner issues would still exist with a larger chip, but hey ho!! If you never try something, you don't know how good / bad it could be!!

So a big thank you to all those on SGL who at times must have felt lile they were fighting the battle by my side!!!

[Catanonia]

Excellent news Sara, glad you have it sorted out now. Frustrating messing with spacing isn't it ?

Looking forward to some nice images from you now, no excuses with 15mins guided

[Martin-Devon]

Well done Sara. Can I ask what you actually used to modify & test the spacing? Presumably these are 2" rings of some sort of different widths? I also want to test this out now since my stars often look elongated to some extent especially on longer exposures. I've done a rough measure & am somewhere in the recommended 56mm distance from flattener to CCD chip, but as yet I've never tried varying this distance.

One other thing - how do you know whether it's a spacing issue, or just poor polar alignment in the first place?

[steppenwolf]

Well done, Sara, your perseverance has paid off finally - just get on and enjoy that 314L now, it is capable of taking great images!

[swag72]

Cheers folks!!

@Martin - I have a locking spacer between the 314 and the filter wheel. I had elongated stars in the top left corner. Decided to change the spacing only by a few turns of the camera in the screw in thread to see if that sorted the problem. I've not measured anything. I know that the spacers I have give me 55mm, but of course that is all with a certain tolerance. I tested it last night with a 30min sub - Round stars throughout.

I know it's not PA etc as I'm in an obs and have a good PA.