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Old 28-05-2008, 07:39 AM
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Robert_T
aiming for 2nd Halley's

Robert_T is offline
 
Join Date: Oct 2005
Location: Australia
Posts: 2,959
Thanks Clive, I really need this sort of advice. I didn't have a clue where to go with ISO so I will give 800 a go. I'm pretty light-polluted where I am... mag 3.

With the flat would I expose using the same settings as for the lights/darks, or is it more a feel thing to get the grey?

ta,

Rob


Quote:
Originally Posted by Alchemy View Post
Any first attempt is a good one, nice to break the ice.

Try upping your ISO to 800 the 40d is a good camera and will easily handle the speed..... as a matter of interest the 350d actually had its sweet spot at 800 for astro imaging, other cannon cameras are very similar (theres a small disertion on this in the help file in Deep sky Stacker).

Flats are a description of how the light falls on the chip through your scope, simply done by placing a good quality white T shirt over the main lens and exposing til you get a mid grey background..... you will notice a gradient or Vignetting at the corners. put into the stacking program it ...Flattens ..out the image so the corners get a bit more exposure applied.

cheers Clive
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