Thanks, Col. I'm familiar with the Petzval design. I have a Tak FSQ-106ED. I was just wondering why the Vixen is not an apochromat. Does it mean they used the extra degree of freedom to correct something else?
Cheers,
Rick.
Quote:
Originally Posted by FlashDrive
Because of the design (a four element Petzval arrangement), the field is flatter than a regular doublet lens would be
There are 2 ' elements ' at the front of the tube.....and 2 ' elements ' at the rear of the tube just in front of the focuser.
Hope this helps....
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