Focal Reducer for visual observation

Hi All
I am thinking of getting a .5 Focal Reducer for my ETX90 Has anybody used a Focal Reducer for visual observation

Howdy,
I wrote a few articles on the Meade 7" MAK and included some experiments I've done with focal reduction. I also use it for viual observation.

Please keep in mind the 7" has a 2" format with much larger field stops. On a 90mm scope, you already have a pretty short focal length. However, your desire for a visual focal reducer leads me to think you want a wide field. If so look at some alternate sources for the reducer. ScopeStuff has several.

On using a .5; well it's possible, but you'll very likely see shome obstructiuon shaddow and vignetting. That didn't stop me. I think a .7 would be better for your application, with about a 26mm EP at the most. Using too long an eyepiece will really exagerate the shaddows. You'll see some vignetting and shaddow, but only in a bright sky. For deep sky, you'll do just fine.

There's my two cents!

Thanks,
Steve
8)

Vaclav Novotny said:

Hi All
I am thinking of getting a .5 Focal Reducer for my ETX90 Has anybody used a Focal Reducer for visual observation

Yes...I've used one of the Baader reducers on my 125. Does it work? Yeah. To a point. Don't think you're gonna slap one on a 40-mm eyepiece and get widefield. What you will get is considerable vignetting. It works ok with medium focal length eyepieces.