upgrade to longer focal length?

[JoeBlow (Joe)]

Happy new year!

I was wondering if anyone could talk me into or out of this...

I have a Skywatcher 150x750 reflector on an eq3 mount that I use as my grab and go scope. I chose this size for its portability and wide views. Though I love this scope, the coma and other edge imperfections are starting to bug me. Also I've been finding myself using high power much more often with this scope.

This got me thinking about swapping it for the 750x1000 version. I figured with a 40mm 68 degree eyepiece I can still get pretty wide fields and it would still be grab n' go size. It has been a very long time since I've used anything slower than F5, so the question is will going from F5 to F6.7 show considerably less coma and better edge correction?

The thought of better collimation tolerance and greater depth of field also sound very attractive.

Is my reasoning sound or am I missing something and I should just stick with what I have?

Thanks,

Joe

[jenchris (Jennifer)]

750 by 1000? Wow that is some piece of mirror.......
What about that with a field flattener.
You can always drop your FR by using a Barlow x2

[The Mekon (John Briggs)]

Originally Posted by JoeBlow

Happy new year!


This got me thinking about swapping it for the 750x1000 version. I figured with a 40mm 68 degree eyepiece I can still get pretty wide fields and it would still be grab n' go size.
Joe

Joe, I assume you mean 150X1000, so the question is what do you mean by swap? An exchange where no or little money is paid? If so go ahead and try. If you mean sell & buy I think you will incur losses that make the exercise futile. Instead you should be looking at a very different scope if you are now wanting better views. An 8"F6 dob for example or a nice refractor - may not be grab and go but still very quick setup.

[JoeBlow (Joe)]

Lol, obviously I meant 150x1000.

Originally Posted by The Mekon

Joe, I assume you mean 150X1000, so the question is what do you mean by swap? An exchange where no or little money is paid? If so go ahead and try. If you mean sell & buy I think you will incur losses that make the exercise futile. Instead you should be looking at a very different scope if you are now wanting better views. An 8"F6 dob for example or a nice refractor - may not be grab and go but still very quick setup.

I agree an 8" F6 is a nice portable general purpose dob, however I already have other larger telescopes. The original idea behind this telescope was a "grab n' go" wide field telescope. An 8"f6 is getting a bit long for ultra wide fields at 1200mm, even 1000mm is pushing it.

I'm planning on selling and buying. I know I'll lose a bit of money doing that, but if it results in much nicer views it might be worth it.
I could buy a cheap coma corrector and a barlow, but I prefer using less glass. So for a litte less money than a coma corrector and a barlow I could get a similar effect with a longer focal length.