Using a focal reducer in an ED80/ED100

[John]

With the right adaptors, can you successfully use a Celestron / Meade f6.3 focal reducer in an ED80 or ED100 ? - has anyone actually tried it and with what results ?.

Cheers,

John.

[bern]

In a word yes

It's often done by imagers and the results are good.

bern

[Ant]

A lot of Russ's results are witht he ED100 and FR.

His images come our really well.

Ant

[russ]

Hi John,

I used to use the Celestron f6.3 with the ED100 and ED80....worked really well.

Russ

[MartinB]

How does it fit?

[Ambermile]

2" to SCT adapter!

Arthur

[MartinB]

Fabrique par Ambermile

[Ambermile]

Well, yeah - but other adapters are available...

[John]

Thanks for the replys folks.

With the f6.3 reducer, how can I work out what the revised FL would be with my f7.5 ED80 and f9 ED100 ? - I'm assuming that it won't be f6.3 !.

Thanks,

John.

[Ambermile]

Umm - 63% shoudl do it, assuming you get the distance from the ccd/EP correct.

Arthur

[russ]

ED100 - new fl = 567mm (f5.7)

ED80 - new fl = 378mm (f4.7)

Hope that helps

[John]

An ED80 at f4.7 - that sounds enticing !! - thanks. One more question - would I need more focusser travel ? - I've got loads of outward travel left but only about 2cm inward travel with my Wide Scan 20mm at focus.

John.

[John]

Me again !! - just to check I've got this right, if I want to do this I need:

ED focusser with 2 inch fitting > 2 inch-SCT adaptor > focal reducer > SCT 1.25 inch visual back > diagonal > eyepiece ?

I hope I've got that right.

John.

[GazOC]

John,

Focal reducers always need more inward travel. My Atik/Antares 0.6 reducer comes to focus (for imaging) in a 1.25" diagonal (and no diagonal) but not with a 2" diagonal.

HTHs

Gaz

[John]

Thanks Gaz, looks like I would run out of inward travel as it stands then - unless I change the eyepieces I'm using.

John.