[Jabroni (Jason)]

Here are my first (well aligned) shots. I'm using an Orion ED80T CF, HEQ5 Pro, Starshoot Autoguider and Nikon D7000.

Shot from my balcony (about 7km from the city), with 10 x 3min exposures. I've stacked them, adjusted levels and cropped a little.

The original shows stars in the centre are in focus, but stars at the edge are out of focus. Is this what a field flattener is for? Do they work on refractors?

Any tips for improvements?