ATM 16" f 3.9 considerations

["Matt Luttinen" <mluttinen@qwest.net>]

Hello all,

I need your advice on the following for my 16" f 3.9 truss scope:

I have (tentatively) decided to go short on my mirror so that I can be
ladder-free and put a large super-finder up on the secondary cage. Upon
looking at the design in Newt, I am shocked that the 100% illuminated
spot
is small (0.23", 0.207*) with a 3.1 secondary (which I have already
purchased).
The 75% spot is 1.722", 1.59*. I will be using a Paracorr with Nagler 22
T4, 
Meade 14 UW, and Nagler 7.

Questions: Is this level of fall-off noticeable? Should I go 3.5" with
the secondary?
Or should I get used to the idea of a ladder and go with a longer
f-ratio and keep
the 3.1?

Jim Fly's Newtonian Telescope Design Planner at:
 
http://home.earthlink.net/~flyj/designie5.html 

shows a 0.12 mag loss for the 14 UWA and a 0.34 mag  loss if I input the

specs for the Nagler 31.

Regards,

Matt Luttinen
Glendale Arizona
33:33:58 N, 112:09:54 W