Focal reducer for 80ED and 8" SCT

[michaelmorris]

I presently have a Meade clone f6.3 focal reducer for the LX200 but this won't even come to focus on the 80ED.

Being a man of modest means I'm looking for a single focal reducer/field flattener that will improve field flatness in both my Orion (aka Skywatcher) 80ED and my 8" LX200 Classic.

1 - Does such a beast exist?

2 - Does such a beast exist at an affordable price?

[Ben Ritchie]

I thought that the f/6.3 reduced did work with the 80ED, but needed an extension tube to reach focus - have you tried that?

[michaelmorris]

Yes, I've tried it, but it doesn't work. My understanding is that the Celestron f6.3 will reach focus, but that the Meade and its clones will not.

[Ben Ritchie]

Ah, that might be it - I had the Celestron f/6.3 reducer and i'm fairly sure that did work (few years ago now, so my memory is a bit hazy). I always thought that they were the same thing though, but clearly not?

Can you try finding a Celestron one and selling your Meade to fund it? It would seem to me to be the cheapest solution that'll work with both, there are a number of reducer/flatteners that work with the 80ED but i'm unsure how well they'd work with a SCT.

[michaelmorris]

Can you try finding a Celestron one and selling your Meade to fund it?

That's one of the options I'm considering.

[Merlin66]

Michael,

There's something wrong here...

The current Celestron and Meade x0.63 reducers are identical and have a focal length of 240mm. They both need a back focus distance of 110mm.

I have a Meade one and can assure you I've used it both on my ED80 and the 10" and 8" Lx SCT's.

Geting the 110mm is difficult on the standard ED80 focuser and I had to machine a special adaptor to get it to fit.

Can you measure the focal length of the reducer you have?

Ken

[Ben Ritchie]

The current Celestron and Meade x0.63 reducers are identical and have a focal length of 240mm.

That's what I thought. ISTR that there was a peculiar batch of Meade reducers at some point, is it possible you have one of those?

[ollypenrice]

That's what I thought. ISTR that there was a peculiar batch of Meade reducers at some point, is it possible you have one of those?

Ben's right, I remember this too... or rather I don't quite remember it! Might well be your problem.

Olly

[Merlin66]

The very first batch of Meade x0.63 reducers manufactured in China were incorrect. The focal length was around 160mm.

If the reducer is marked "made in Japan" then they will be 100% correct.

It's an easy thing to check......

[blinky]

I have a Meade 0.63 reducer and have never tried it in my ED80 - I use a WO FFII for that. So...... Are you guys saying I need to extend the CCD 110mm from the lens of the reducer? I mean is that not exactly the same as when using it on the SCT?

[michaelmorris]

My focal reducer is a Meade clone from Scopes 'n' skies, It doesn't have the Meade logo. It even says 4000 series on it, just not Meade. I'll try it again to check, but I'm certain I couldn't get it reach focus.

[Merlin66]

Blinky,

the design spacing between a x0.63 reduecr lens and the CCD image plane will always be 110mm independent of the telescope. It doesn't matter if you use a SCT, refractor, Newtonian etc etc the distance is always 110mm to achieve the x0.63 reduction.