Re: [guide-user] Fw: 7observing

Paul Schlyter Jan 26, 2002

>> Georgiana,
>> What is the advantage of stacking 10 3-second images over 1 30-second
>> image?
>
> "Guiding" is the simple answer. Even the poorest of drive motors will
> generally produce a satisfactory 3 second exposure, but you need a good
> sturdy mount and a decent drive system to get a good 30 second image.

Another reason is graininess: by stacking 10 images of 3 seconds you
also average out the graininess of each image, compared to using just
one image of 30 seconds.

And seeing is a third reason: if yoiu have, say, 100 images, you
can choose those 10 images which had the best seeing during exposure.

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Paul Schlyter, Swedish Amateur Astronomer's Society (SAAF)
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