Advise for a beginner

[johngk]

After having my scope for nearly 2 weeks i finally managed to get out last night and get it all polar alligned and set up properly. I completed a 2 star allignment and decieded to take a look at M31 Andromeda which i saw no prob at all. Great......

I thought i would take a quick 30sec shot to have a look at focus etc and i have star trails can someone help me with this please.

Equipment is:

Skywatcher 80ED Pro HEQ5 Pro GOTO Mount, Canon 1100D.

Heres the image:

[John]

What scope and mount are you using ?

[johngk]

Sorry forgot to mention scope and mount.

Skywatcher 80ED Pro HEQ5 Pro GOTO Mount, Canon 1100D.

Many thanks

[hemihaggis]

hmm .. im sure someone more knowlegeable will pop in soon , but i would think your polarr align was a bit off . a rough alignment is fine for visual , but you have to be super spot on for photos , there are many different ways of achiving this , inc rotating polar scope ,then there is drift align ect ,

but well done for your first pics , looks good

[steppenwolf]

That's certainly a lot of star trailing for a 30 second image with that mount and telescope.

Things to check are:-

1. Ensure a really good polar alignment

2. Balance the telescope very accurately slew to your object and then slightly unbalance the mount so that the rising side is a little heavier

3. Ensure that the RA and DEC clutches are really tight

4. Make sure that no cables are dragging

5. Check that the mount is tracking at Sidereal rate

[johngk]

Thanks for the advice, i will make sure i take a lot more care and get a better polar alignment next time round.

[Double Kick Drum]

Two Messiers at the first attempt.

I'd be more than happy with that!

[Matt2011]

Hello, How do you unbalance the mount in step no 2. Thanks

[steppenwolf]

Once you have acquired your target object and, therefore, found out for sure if it is the telescope or the counterbalance weights that are on the East side of the mount (i.e. on the side that is 'rising') you do the following:-

1. if the telescope is rising, slide the counterbalance weight 2cm UP the counterbalance shaft

2. if the weights are rising, slide the counterbalance weight 2cm DOWN the counterbalance shaft

What you are trying to achieve is a small bias that keeps the RA axis under constant drive. This is particularly important when guiding but worth doing unguided too.