Astrophotograpy Question

[robwin]

Last night i was out with my Meade LX90 10" trying some photos of M57 with a 350D testing out the bulb exposure taking pictures at around 4 mins but when i looked at them on my laptop there was star trails only small ones but they are there.

I also got them using the HEQ5 mount with the Equinox 80mm.

Can anyone help with this problem.

Thanks

Rob

[Kai]

Sounds like you were slightly out on Polar alignment.

Btw 4 mins is very good if unguided.

[geppetto]

4 minutes is realy pushing it with an unguided scope...

Do a drift align to get the best you can but if it were me,

I would take 4 one minute shots and stack rather than one 4 minute shot.

[robwin]

Thanks

Something i have not done yet stacking them but i will give it a try.

Rob

[Albireo380]

Hi Rob,

An unguided exposure of over 30 seconds using your LX90 is probably about the best you will get - perhaps pushing to 45 seconds if using a wedge (Equatorial mode rather than AltAz).

I find my HEQ5 is okay for about 60seconds on a resonably quick polar alignment (with an 80mm 'fract) - anything longer takes alot more careful polar aligning.

Tom

[Ant]

It's the luck of the draw.

I'm fairly lazy when it comes to polar aligning - but to me it seems that the more effort I put into Polar aligning the worse the trailing is!!!

I have managed 5 minutes with the HEQ5 (300D and 8" F5), there was some trailing but not a great deal. Then other times I'm lucky if I can get 30 seconds...

4 minutes is quite good!

Ant