Piggyback shots on an ETX 125

Howerye.
I picked up a piggyback bracket for the ETX 125 from Andy at Whirlpool
and I've yet to try it out (damn weather)
Just wondering have any of ye done a bit of work with this or similar set up?
How will it fair out for long exposure shots as in how long etc?
I know it's a lot to do with the accuracy of the scope but most images I've seen of the set up show it in Alt / Az mode?
Is this right, I would have thought it would have to be polar aligned.

In Alt/Az mode the field will rotate around the central point.

You'll need a "field de-rotator".

Easiest to set up the scope as a polar aligned equatorial.

Peter

you can try getting images around the meridian, this is where field rotation is at the minimum, otherwise you will need to polar mount the scope.

Try this site:

www.physics.brown.edu/physics/labpages/p...r%20Meade%20ETX1.htm

One is interested in Cosmology, not photographs.

Mind you.

Time lapse on Altazimuth mount while is Saturn dead centred would be fun.

Saturn would rotate like a windmill.

Peter.