whats is going on with this

[Daniel-K]

can some one please tell me whats going on here my PHD graph is like a duck pond but still have trails, i have been told by Bern at MA that i dont need a CC with the CCD cause the chip is small but i personally think i have come can some one please elaborate to me whats going on im getting stressed now as i sold my very nice DSLR on this advice that all would be ok

[jnc71106]

possibily flexture thats what happens nice flat graph but you have star trails. check that you have everything screwed down tight on rings, focusers etc

[Martin-Devon]

yep I'd look at flexure as well - often people point the finger at the guiding, but flexure can be a real driver of egg-shaped stars as well. Also check that the CCD is sitting absolutely square to the imaging train. Good luck...

[ollypenrice]

Martin's shortlist is the same as mine. It's likely to be either flexure or tilt because your guide graph is a work of art!!

Some of the budget CCD cameras are devils for having tilted chips so if it isn't your focuser try looking into that. I think Altair Astro sell a generic tilt adjustable device to allow for any form of tilt to be rectified.

The elongation is all in a single straight line but so far as I can see that could fit either scenario. What happens if you rotate the camera? Does the elongation change with it? That's an important test.

Olly

[Daniel-K]

well the CCD is going back as the glass the sits infront it fogs up when its cooled and there is bits falling off inside and landing around the ccd area 2nd time its going back not happy. thanks for the advice guys will try it out when it comes back

as i was getting trails i tried to eradicate the error by adjusting the settings which led me to this nice graph but when the trails still appeared i was not happy, think i might just get a refund

[ollypenrice]

well the CCD is going back as the glass the sits infront it fogs up when its cooled and there is bits falling off inside and landing around the ccd area 2nd time its going back not happy. thanks for the advice guys will try it out when it comes back

as i was getting trails i tried to eradicate the error by adjusting the settings which led me to this nice graph but when the trails still appeared i was not happy, think i might just get a refund

Which of the cameras in your sig is this one?

Olly

[Daniel-K]

It's the mammut bright star :/

[Daniel-K]

ok so i have rulled out flex as its the same in a 5 sec subs as it its in a 4 min sub. i think its cause the chip is small its showing the coma so im buying a coma correcter to see how i get on that way