4 replies to this topic

[mike_k]

Field flatteners in an already flattened scope.

 

I’ve been thinking about using a reducer to speed up my scope a little in my quadruplet field flattened refractor.  But checking all the parts catalogs it seems 75% of them are combined reducer & flattener (and usually designed for specific scopes), and another 20% are designed for SCTs.

 

What would a twice field flattened image look like? Or corrections for the few but tiny weaknesses of SCTs? Are they all going to be over correcting for something?

 

Are there any known plain vanilla, non-correcting 0.6-0.7 field reducers of decent quality (I guess that makes it Tahitian vanilla bean)?

[Ernest_SPB]

In general it is a bad idea to use corrector for already corrected image. Overcorrection looks like not correction with just another sign (orientation) of aberrations.

[Mike W]

When I overcorrect in my car I usually run off the road!

[Jon Isaacs]

I believe there are correctors designed for the Takahashi FSQs and the TeleVue NPs.. 

 

Jon

[Riaandw]

Your aberrations will depend on you sensor size. If you have something laying around there's no reason not to try.

 

Something like the AP ccd67 only reduces. https://www.astro-physics.com/ccdt67

 

Lumicon makes some 0.5x plain reducers. I believe it's just binocular front objectives.