[Lester]

G'day all,

Justs started to experiment with the Canon 20Da using 50mm f1.4 lens mounted piggy back on EQ mount. Took some shots last night Orion and Crux area tried 400 & 800 ISO f1.4 and f2 with exposures ranging from a few seconds to 4 minutes. I was happy with the nebula that was revealed eg Barnards Loop, Eta Carina But the stars on all except the short=12 second exposures were very bloated.

At first I had focus set on infinity and later I backed it off just a fraction but that made the images out of focus.

Light pollution is not an issue from my area. I don't believe focus is causing the bloated stars otherwise the short exposures would not show pinpoint images.

Is there a filter that can be used to minimise or elliminate bloated stars?