Thread: Darks/lights
View Single Post
  #4  
Old 07-12-2008, 03:04 PM
Octane's Avatar
Octane (Humayun)
IIS Member #671

Octane is offline
 
Join Date: Dec 2005
Location: Canberra
Posts: 11,159
Mark,

Use the histogram display of your camera to ascertain the correct time value for the exposure. Typically, you'd want the histogram to peak somewhere between a third to half-way across the histogram.

The time value will vary according to the light source used to take your flat.

Regards,
Humayun

Quote:
Originally Posted by batema View Post
A quick question Leon if you get back to this thread. If you take flats at duck pointing the scope straight up, how long should you take the shot for or will the AV on Canon 400d automatically do this for you? are you also looking for a difference in the grey/whitish colour of flats so you have the edges, in particular the corners, a different shade to the centre?

Mark
Reply With Quote