View Single Post
  #1  
Old 08-02-2008, 04:18 PM
Dennis
Dazzled by the Cosmos.

Dennis is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 11,820
Eta Carina and Canon 40D - where's the red???

Hello,

Well, the experimentation continues with the 40D and deep space work. Last night, I learned that using a DSLR on fainter DSO’s is very, very different in terms of exposure duration required, compared to the SBIG ST7 which has a much higher quantum efficiency and is cooled.

Here is an image of Eta Carina cropped from the full frame. Noticeably, the red stuff is missing as is most of the data! This is a combination of 3 x 5 minute sub frames.
  • Tak Mewlon 180 F12 with Tak Reducer/Flattener around F9.6 so it is still a sloooow system.
  • Canon 40D, 3 x 5 minute exposures at 400ASA.
  • Processed in ImagesPlus and CS3.
There is a definite price to pay when stepping up to larger sensors and colour, in cost, set up, capture and processing! I might just stick to DSO's brighter than mag 4!

Cheers

Dennis
Attached Thumbnails
Click for full-size image (Eta Carina.jpg)
114.2 KB127 views
Reply With Quote