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Focal reducers for visual use

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This may be a naive question, so apologies up front.

I understand how focal reducers can help with imaging, but can they be of benefit for visual observing? I have an ED80 scope and guess it would give me a wider field of view.

If so, how does it work with diagonals and how would you link it all together?


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You can use a focal reducer on an Meade SC F 10 scope, I have done on mine, it reduces to F6.3 but in truth there are no real advantages if you have the eyepieces I have. The maximum you can use in this scope is 28mm with a reducer which exquates to much the same as 41mm without in terms of purely FOV, the power is different.

As to whether you can on other scopes at shorter F/Ls I rather fancy not as I have never read of it or for that matter heard anyone actually trying it.

Personally I would not bother and often wish I had never bought the reducer as it has sat collecting dust for ages, after playing.

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Technically, they could provide a wider true field of view if you used a 2" focal reducer with a 1.25" eyepiece, but you'll get much better image quality with a 2" eyepiece of longer focal length or wider field of view.  I've attached a 2" focal reducer to multiple eyepieces without finding anything usable.  YMMV.  Reaching focus can be a big issue as well due to in-travel requirements.

I've used them to good effect with binoviewers to regain some field of view after using a 2X nosepiece to reach focus.  The 2X goes on the front of the 1.25" diagonal and the 0.5x goes on the front of the binoviewer.  There is some added field curvature and vignetting, but it's a tradeoff I'm willing to live with to get a wider binoview for cheap.  When I want a clean, high powered image, I just remove the 0.5x and move the 2X to the front of the binoviewer.

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