Effect of CA on the size of the exit pupil?

Hi all,

Assuming I'm using:

exit pupil = EP fl/(scope fl/primary objective)
what is the effect of the central obstruction?

cheers
Gaz

wrote:
what is the effect of the central obstruction

Nothing. A working definition of the exit pupil is "the image, formed by
the eyepiece, of the aperture". The aperture, and hence the exit pupil
size, is unaffected.

Best,
Stephen

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Stephen Tonkin wrote:
wrote:
what is the effect of the central obstruction

Nothing. A working definition of the exit pupil is "the image, formed
by
the eyepiece, of the aperture". The aperture, and hence the exit
pupil
size, is unaffected.

Best,
Stephen

Remove footfrommouth to reply

--
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ Stephen Tonkin | ATM Resources; Astro-Tutorials; Astro Books +
+ (N51.162 E0.995) | http://astunit.com +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

Thanks for that. It's just I'd uploaded an Excel spreadsheet that I'd
made to calculate EP values to the Yahoo Chinese refractor group. But
forgot to add the creavet that I hadn't allowed for scopes with a CA.
thanks again
Gaz