[Gimp-user] Reducing noise with multiple exposures

[Toby Haynes]

giuliogiuseppecarlo at interfree.it wrote:
> I'm trying to reduce noise using multiple photos of the very same subject, using both a tripod or simply repeating a scan a number of times ( i have a flatbed scanner with a lot of noise especially in dark areas... )
>
> So far i have tried with my old broken camera that had powerful noise at 400 iso  and first results are not bad at all.
>
> Samples:
> http://img90.imageshack.us/img90/6967/prova1wc2.jpg
> http://img131.imageshack.us/img131/448/prova2xh7.jpg
> http://img116.imageshack.us/img116/7589/prova3on7.jpg
> ( heavy purple fringing is probably due to the fact that i choosed 5/7 of the max resolution, 5 mp instead of 7 )
>   
You might consider the Anti-Lameness Engine, which is expressly designed 
for exactly this sort of task (including re-aligning the images and 
suppressing noise).

http://auricle.dyndns.org/ALE/

Hugin (http://hugin.sf.net/) is useful if you need to exactly align a 
number of images prior to any stacking. It can also be used to remove 
chromatic aberation with a little care (although it's fiddly and time 
consuming).

Cheers,
Toby Haynes