Chromatic abberation + IR

[pbadcock@xxxxxxxxxxxxxxx]

Hi all,
        I was pondering over all the ways used to compensate for the slightly 
out of focus IR rays of light (larger depth of field, focus adjust, IR filters 
with non zero diopters!..)and I came up with another one, well I think I did.  
I'm assuming that the majority of your lenses these days have special coatings 
on them to avoid chromatic abberation in the visible range, This attempts to 
correct for the fact that light of different colors refracts through the 
lens(es) at different angles.  Why not extend the corrective attributes of the 
coatings down to IR as well?  Is there a trade off involved? Is it too 
expensive? Does it already exist??
I'd be interested to find out if anyone knows about this.

regards
Peter


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End of INFRARED-PHOTOGRAPHY Digest 270
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