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Subject: Re: vote by atlanticp95
By: Anonymous (xxx.xxx.223.11)
Date: 10/23/2003 03:34:35 pm PDT
>Taks and APs are just like cars. Take a Ferarri for example, and a Mazda Miata. The Ferarri is 10x the price and people buy it for the name and obvious performance. But you can drop a $10,000 upgraded engine in the mazda and it will beat the Ferarri. So why don't people buy suped up Miatas? Because its all about the title. Likewise, this Mak-Newt (Miata) out-performs any 4" APO.
I understand your concept, but there is no way 10 thousand dollars will make a little miata a ferrari eater! HA!! Maybe a better example would be dumping a balanced and blueprinted big block into a camaro...
Subject: Re: vote by xxx.xxx.234.249
By: Anonymous (xxx.xxx.1.115)
Date: 05/05/2004 03:32:39 am PDT
> Stars focused through most of fov - extreme edges show coma but - hey - its an f/5 fast mirror.
The MN56 is not f/5, it's f/6. This reviewer repeats his "f/5" error several times in his report.
> The fast primary mirror makes pinpoint stars across entire fov through edges impossible - but with proper cool-down it's only apparent at very edges. They're not comets or anything gross - they just go out of focus as you near the edges. That's why I gave the optics only a 9 rating.
Sounds like field curvature and/or astigmatism/coma in his *eyepieces*. Maks are reknowned for wide _flat_ fields. The official specs of the MN56 include:
-- photographic field = 13.5 mm diameter;
-- spotdiameter at edge of photographic field = 11 micron.
This is superb sharpness at a considerable distance off-axis. It would have to fall apart completely, further off-axis, at a rate faster than coma becomes apparent in normal f/6 Newtonian paraboloids, to match the decription given by this reviewer. I doubt that could be the case, so I would suspect the eyepieces or collimation, rather than the telescope optics themselves.
Subject: Re: vote by xxx.xxx.162.101
By: Anonymous (xxx.xxx.82.213)
Date: 08/14/2008 01:35:16 pm PDT
>Just finished extensive testing.
>Epsilon Lyrae double-double cleanly split at 100X with black between stars.
>Several large and small globulars resolved.
>The disc of Uranus clearly seen at 400X-but no detail.
>M51 spectacular with spiral evident when using averted vision.
>My CG5 mount is a perfect match. I use Vixen motors and controllers-the celestron motors and controllers are weak and poorly constructed.
>Contrast is very high. Helical focuser is sturdy, precise, but clumsy at first.
>My 4 inch APO is now gathering dust in the corner
You can make out spiral structure in M51, with averted vision, with a 5" aperture??!! Where (and how dark a place) in the world are you viewing from? I still haven't had my 12" somewhere dark enough that I could more than barely discern spiral structure in it...
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