At 07:15 AM 4/30/98 -0700, ric ecker wrote:
>
> Both use a thick mirror flat, something that I didn't mention because
>it was brought up elsewhere is the way each dia. fits to the scope. The
>Meade has the screw on mount which can get tight and the TV has the
>barrel and locking screw which is more convenient. I use the TV on my
>OTA and the Meade dia. on my 4" 2045. The Meade's are made in the USA
>and are 10 wave flats. Both seem optically identical.
>
An additional question - is there any disadvantage to the barrel and visual
back assembly arrangement over using a screw-on diagonal (re problems if it
is heavily loaded?). I am aware of the alternative problem, of rotating
the diagonal with screw-mount, and Nigel Burge's excellent solution :

>(I have the Meade 2" diagonal and also found rotation a pain.
>However I cut two washers (gaskets) out of thin rigid plastic and put them
>either side of the locking ring. You have to unscrew the barrel of the
>diagonal from the body to get the inner washer on.
>
>I was amazed at the difference it makes. I can fully tighten the locking
>ring by hand and the diagonal can still be rotated by hand and stays put
>with friction. It does not move under its own weight even at 90deg loaded
>with a heavy eyepiece.

(Nigel - "thin, rigid plastic" Nylon, TFE or what?)


A related question - Does anyone have any information regarding whether any
of the flip mirror rigs (especially re Van Slyke and Taurus tracker III)
have mirrors whose quality compares to the TeleView 2" diagonal? I am
debating adding a flip mirror rig, and wonder (if I left it attached all the
time) whether viewing would suffer relative to a dedicated 2" diagonal.

This is for my Meade 10" LX50. By the way, I got an opportunity to trade
views recently with a dedicated owner of an old, well-cared-for 12-1/2" Cave
Astrola - I was delighted to see that my image quality (using Meade 4000
EP's) was very comparable to views in the 12-1/2" with Brandon oculars.
Made me appreciate Meade even more.

Thanks for any info. David
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