Quote:
Originally Posted by glend
Allan I reckon that the coma would drive most imagers crazy at F/3 regardless of the benefits, and collimation would also be a constant headache. As to the weight, there are much lighter alternatives if you have some ATM skills - my 10" f/5 imaging newt OTA only weighs 12.6kg, uses carbon fiber struts. There are a fair number of exotic designs emerging in the market but you have to consider the night to night use and management of the setup. The quest for ultra low F numbers is nuts in my opinion, and not worth the alleged benefits in exposure time savings. For imagers who are setup to guide their mounts the potential of shorter subs is not that great an attraction to justify the problems you would buy into at F/3.
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Hi Glen,
thanks for your reply.
I don't agree that it is nuts to consider f/3.
That scope is a carbon fiber tube which should give high stability
for collimation - it's not a cheap scope.
The bad weather & lack of time means only fast instruments
can collect enough data in the short time windows opened.
I wrote to TS & they have no pictures taken with this f/3 scope.
I have written again as I don't want to be a guinea pig.
One problem is my RCC1 coma corrector which is designed for f/4 to f/7.
Even the
ASA 2" Coma Corrector Quattro 1.175x they recommend
says it works only from
from f/4 to f/6.
My KAF8300 chip has a diagonal of only 22.5 mm - not too large.
I think the RCC1 would still work -
see mine here:
https://www.flickr.com/photos/247194...in/photostream
I'd love to see some result pics.
cheers
Allan