Subject: APO refractor apeture
From: Jim Beam
Date: 9/22/2004 5:17 AM Eastern Daylight Time
Message-id:


I read different numbers for how much you can milk out of a specific
aperture. I am considering a 7" APO.

Some people say 30x per inch, thats it for detail. Well, thats only 210x
which seems conservative for a 7" APO.

Many people say 50x per inch, and thats 350x for a 7" APO, sounding better.

But on nights of superb seeing, how far can you take a superb 7" APO, like a
TMB or an AP? Can you view Saturn at 500x? 600x? When does decreasing
brightness become a problem, and when does additional detail fail to appear?

Thanks
JB
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With the excellent made APO's like AP, TAK ,TMB, you can use up to 100x per
inch in super seeing! The image brightness starts to really fall off at such
powers, but for the moon and planets you can still see detail...

Chas P.