Quote:
Originally Posted by David Fitz-Henr
My interest though is in the practical application of drizzling to amateur images; to what extent is random dithering compensated for by taking additional sub-frames, etc. Ie. will the purported gains in resolution for undersampled amateur images be realised?
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David resolution gains can only be made if the optic has better resolution than the sensor.
First law of the Universe 'there is no free lunch'.
By upsizing an image it is just being resampled with a loss of overall signal to noise. With many of these randomly dithered upsized images then stacked, both S/N and resolution are enhanced. More images then more enhancement.
Have a look here
http://en.wikipedia.org/wiki/Nyquist...mpling_theorem
Shannon was on to this problem when I was just a young boy.
His Theorem applies to temporal resolution of a time dependant signal. It is equally valid for spatial resolution of a two dimensional array.
Bert