Comparison
Of Light Pollution Effect on
Canon 20Da vice the Canon 40DH
 

 

Canon 20Da; M31;
South Riding, VA. (01-25-08)

Canon 200mm f2.8L; f5.6;
3 min frames; 12 image Stacked
ISO 800; (dark subtract) no autoguiding
Canon 40DH; M31;
South Riding, VA. (12-06-07)

Canon 200mm f2.8L; f3.2;
2 min frames; 10 image Stack
ISO 800; (dark subtract); no autoguiding