One of my problems on a bad night!

[Fay]

I was trying to do NGC 6946 a spiral in Cepheus, it was at the zenith, suddenly I realised the guiding was useless. I thought I would realign the guide webcam & saw that the stars were moving in the opposite way to the arrows on the goto handset. Nothing I could do would change it. I decided to go east again & all was ok. Is this what is known as a meridian flip? 

It was a bad night, could not get any image on the SX chip, after 3 hours, & 4 system restarts I finally got the spiral in my sights but then got the guide camera problem.

I also wanted to use the WO for the wide FOV, but could not get the subject on the chip, as it does not have a finderscope  so reversed cameras, although I have been told it does not make any difference not having it's own finderscope.
I wanted to put a FR on the SX but could not get near enough. to focus, with the filter wheel on there, as near to NGC 6946 there is a nice open cluster.
I think it is best to have the FR close to the chip, I was thinking of putting on the far end of the filter wheel but think it may be too far away & I will get vignetting still.


Fay

[Mike]

Fay, could you not have mounted your finder on your guide scope? Did you use the ED80 as a guide scope?

I always align my finder with the image on teh sscreen at the start of the night. Just find a very bright star, Vega is good, align the image in the centre of the chip, then align the finder with the same star. That way you know the finder will always be pionting at exactly what area your CCD is looking at.

[Fay]

Mike, I have not thought about mounting the ED80 guide scope on the WO.
I mean, it should be ok as it is. The ED80 is about the same distance away from the guide scope, as the WO would be.
I did have a frustrating night so I will try again. Nothing was on the chip, I am thinking that I could have put 21 instead of 20 in the time when setting up a couple of times.

I do always align the finderscope with the image on the screen. I just could not find anything on the chip.


Fay

[Mike]

So what were you using as your guide scope?

An easy way to test if your GoTo is working and you can't see a faint object is to make it GoTo something bright and obvious. Then check the alignment.