[alocky (Andrew lockwood)]

Hi,
Can anyone tell me how to avoid having very different image intensities from avistack? Process I'm trying to make work is:
1. series of 10 or so avi files from my DMK41 (all camera settings held fixed)
2. run these through avistack in batch processing mode
3. load raw fit format output into registax for wavelet enhancement.
At this stage, I notice that some images are a lot darker than others. Are there any hard-to-find switches in avistack or registax that avoid changing the intensity stretch of the images? I certainly haven't told them to do it..
Thanks in advance,
Andrew.