[HDR-photo] Film scans and registration

[Lincoln Michaud]

Hi folks,

I am patiently(or not so patiently) waiting for my slides to be   
processed so I can try my hand at some hdr with my PS  CS2.   My  
reading suggests that there is often an issue with scans from slides  
that don't register or line up properly.   Some have described  
inconsistancies as 'clouds'  And sometimes downright artifacts.   I  
am very concerned with getting highly resolved images and this  
bothers me.  If it is a glaring problem, you should be able to see  
it.  However, how can you tell when slight mis-registration degrades  
the image?  Is there a good way to check for these anomalies?

Thanks for any input,

               Lincoln