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Old 21-06-2007, 12:49 PM
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RB (Andrew)
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Quote:
Originally Posted by acropolite View Post
Col if you are going to use RAW you must manually take dark frames, the in camera noise reduction isn't applied to RAW images.
Quote:
Originally Posted by g__day View Post
Agreed, but is it for sure on a 400D thata RAW shot, with a dark frame automatically subtracted - isn't actually doing anything as said above - or has this been addressed? Anyone know from a definitive source for sure?

Thanks!
Dark frame subtraction (In Cam Noise Reduction) is most certainly applied to RAW frames if switched on in the custom settings.
Here I've posted two frames, both 1 hour long exposures taken in RAW mode on the 20Da. The first has no noise reduction applied, the second has noise reduction turned on (which takes the total time for the complete frame to 2 hours).
These were both straight out of the camera and only resized for the forum.

As can be seen, the first has more noise but does not exhibit much amp glow because the amp is switch off during the exposure.

The second exhibits less noise but amp glow is more evident since the amp is used during the exposure for the in cam noise reduction algorithm.
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