3rd July 2010

M13
10" Newtonian, SXVF-M25C, 40x1minutes
This is the first image with the SXV camera with the Baader coma corrector fitted. Stars are nicely round over most of the frame. To get the required 55mm distance from coma corrector to imaging sensor, I used a Varilock adjustable extension tube (20-29mm) and a fixed 15mm tube.
The lightbox has also enabled me to use flat frames properly, so the earlier vignetting problems are now gone.
 
   
 
M57
10" Newtonian, SXVF-M25C, 60x30seconds
Still testing the coma corrector. There has been some loss of focus in shifting from M13 to the ring nebula - stars are a bit oval.
 
   
   
9th July 2010
M81
10" Newtonian, SXVF-M25C, 22x3minutes
Exposure times increased to 3minutes. Numerous fainter stars now visible.