Re: [APML] Traveler as guider scope?

[Gene Horr <genehorr@texas.net>]

One other note about using relatively heavy instruments as guide scopes.
My experience is with a 3" triplet f/6 and a 4" doublet f/8.

Whether mounted bolted to the main tube, or using the Losmany DSS, I 
always had flexure when using one tube holder.  The only I found to
eliminate flexure with this setup is with two tube holders mounted
as far apart as possible and the clamshells bolted _tight_.

As others have mentioned, in many respects a small light 50mm - 80mm
f/9 - f/12 works almost just as well and has far fewer flexure problems
assuming quality focuser, etc.  Yes, guide stars are fewer/dimmer, but
you can now add adjustable solutions that will not introduce flexure
problems.

Gene Horr
genehorr@texas.net

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