View Single Post
  #113  
Old 25-02-07, 17:54
Dave Smith's Avatar
Dave Smith Dave Smith is offline  
Senior Member
 
Join Date: Dec 2005
Location: Maldon, Essex
Age: 84
Posts: 576
Default

Don

I have been looking at photos of a total lunar eclipse I took in 2003 and find that the ratio of the time exposures from full Moon to eclipsed Moon are 1 to 2000.
i.e. I used 1/500 s for the full and 4 s for the eclipsed. All other factors were the same.

The Moon moves relative to us at 15 arc seconds per second. The diameter of the Moon is 0.5 degree which equals 1800 arc seconds. So in each second of exposure with a fixed mount the Moon will move just under 1% of its diameter. I'll leave you to judge whether that would be acceptable or not. It may be worth trying with as high an iso as the camera permits (or use RAW) and possibly stretching the result in photoshop. What I am saying here of course only really applies if you want a detailed red Moon. A small red Moon as part of a scenic shot could be much easier.

This is probably all quite academic as it will be cloudy !!

Dave
Reply With Quote