averaging many images to a single image

[magick]

We tried your command with ImageMagick 6.2.8-1, the current release, and it worked as expected without any complaints.

[anthony]

In other words you are a Window user, runing things in a case sensitive UNIX environment A problem I see all the time in the university I work for.

NOTE: -average only works with images that are all the same size.

Also for two images using a composite -blend 50 is the same as average.
See
http://www.cit.gu.edu.au/~anthony/graph ... ose/#blend
http://www.cit.gu.edu.au/~anthony/graph ... s/#average

Question, whay are you averaging 50 images?
Sounds like something that should be mentioned in IM Examples.