2.3mm any good for planetary viewing?

[Puglets]

I have purchased a 2.3mm celestron xcel to view planets was it a waste of money? 

[John]

It all depends what scope it will be used with.

[Puglets]

Celestron nexstar 8se 

[John]

The eyepiece will give 869x magnification with that scope. The practical maximum is 250x maybe a little more on a really good night.

To get the magnification you divide the focal length of the scope (2000mm) by the focal length of the eyepiece (2.3mm) = 869.565x.

Something around 8mm would give you a good workable maximum power.

So, no, I'm afraid it's not a good eyepiece choice.

[sharkmelley]

If you are using it on a Celestron 8se,  the scope focal length is 2000mm so the 2.3mm eyepiece gives a magnification of 2000/2.3 = 870x

But the aperture is only 8" (sorry about mixing inches and mm!)  and it is reckoned that 50x the aperture (in inches) is the maximum useful magnification.  So your maximum useful magnification is 400x.

So the eyepiece is giving twice the maximum useful magnification i.e. you are magnifying the image beyond the capability of the telescope. 

Mark

[Puglets]

Ah [removed word] thanks john 

[Moonshane]

If you have only just bought it new and online then the seller is obliged to allow a return. Maybe exchange it?

If bought used I would sell on unless buying a different scope of 500mm approx focal length.

[scarp15]

11mm TV plossl is a good workable eyepiece for observing planets in this scope, 2032mm FL = 185x. Not recommended if you observe wearing glasses, as eye relief is a little tight for some, personally though I got on fine with it.

[ghostdance]

I agree. 2.3? Ouch!

I'm still smarting from a hasty purchase of a 2.5!

I'm with scarp15 on the TV plossls - 11 or 8 are great on planets. I was just outside looking at the Moon & Jupiter with both - very sharp clear views. Til the murk rolled up...sigh...

[Puglets]

Ok will quickly return it like it never happened right...

[faulksy]

you want something around the 10mm fl to start with, or like scarp said . something like this would be great

http://www.firstlightoptics.com/baader-planetarium/baader-classic-ortho-bco-eyepiece.html

[happy-kat]

Magnification is not everything, the view if smaller but sharp is so much nicer than big and blurry.

The seeing conditions are so variable that it is not always possible to get a high a magnification as theoretically any telescope might do just by number crunching.