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View Full Version here: : Please recommend an 80mm refractor that doesn't need an focal extension tube


Gem
01-04-2012, 09:45 AM
Hi all,

I have been using a cheap 80mm refractor on a photographic bracket on my 9.25" SCT OTA for guiding. The flex is terrible. It needs a 50mm extension tube to focus with my QHY5. I am looking at switching to a ring mounted guidescope. Two rings has got to be better than one photographic bracket! In addition, I want to find a reasonably priced 80mm OTA to replace the current one, if it is possible to find one that doesn't need the extender tube. I hope this will solve much of my guiding issues.

Any suggestions? :)

mithrandir
01-04-2012, 07:12 PM
Depending on what you mean by reasonable, Bintel do a guider package with an ST80 and all the mounting hardware. You'll need to specify the OTA it is to go on to get the right dovetail and radius blocks. You can get it without the guide camera and use your QHY5.

I have one on my C8, except I have a 1.25" flip mirror instead of an extension tube.

They also have a mini-guider package. I have one of those for my other OTA, but haven't had time or weather to set it up.

Poita
02-04-2012, 09:54 AM
Seriously, I'd consider ditching the ED80 and get an OAG.
The QHY5 is sensitive enough for most targets and the problems just disappear completely.

Gem
02-04-2012, 05:49 PM
OAG = ???

The bintel package still needs an extender tube I believe.

Thanks for input! :)