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Old 03-06-2008, 10:10 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 Dennis - great info. At the moment (and assuming I will ever be able to image again with this damn weather) I am using Images plus to control the camera and setting it up to take a range of Lights then a range of darks... do you know if I can use the ICNR with images plus just doing a run of lights or will this over-ride the ICNR?

cheers,

Rob

Quote:
Originally Posted by Dennis View Post
Rob

ICNR is where the Canon 40D automatically takes “Dark Frames” after each light exposure.

When this is enabled (User sets “C.Fn II–1” to “2=On”) then the 40D will take a Dark for every exposure over 1 second.

So, when you take a 3 minute exposure of say, M83, the 40D will automatically begin a 3 minute “Dark” exposure (ICNR) as soon as the M83 light is completed. This effectively doubles your imaging time, i.e. 3 min M83 + 3 min Dark = 6 mins total.

On my SBIG ST7E, where the cooling temperature is regulated, I have the luxury of taking say, 10 x 3 minute lights of M83 consecutively, followed by say, 5 x 3 minute darks at the end of the imaging run as the chip is at the same temp throughout.

I think that Bert has investigated ICNR on the 5D fairly comprehensively and IIRC, his recommendation was to use ICNR rather than switch it off and try to apply separate Darks later on.

Cheers

Dennis
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