Eyepices - the differences

[Jim]

Hi, I'm still quite new to astronomy and am finding this forum so usefull!I did want to ask what are the differences between the various eyepieces, such as Plossl, Super Plossl, SR, H, orthscopic etc etc? And I wear glasses so should I be buying 2" eyepieces? Thanks.

[Moonshane]

this http://www.swindonstargazers.com/beginners/eyepieces.htm is a good general overview.

[Jim]

Thanks Moonshane!

[YKSE]

Here're some more links:

http://www.astrosurf.com/luxorion/reports-epsuggestions.htm

http://www.chuckhawks.com/common_eyepiece_designs.htm

http://www.actonastro.com/eyepieces.htm

http://www.cloudynights.com/item.php?item_id=366

[Jim]

That taught me a lot thanks. I was thinking about buying this: http://www.telescopehouse.com/acatalog/info_BC116.html Do you think its a good buy?

[wookie1965]

Most eyepiece sets are not worth the money as you wont use all the eyepieces and the filters your better spending money on a good high, medium and low magnification eyepiece to suit your scope then you will get more out of them. That is what i did i was going to buy the very same kit and was advised not to.

[Jim]

I see, why wouldn't I use all the eyepieces?

[ronin]

The eyepieces you mention are simply different designs - in simplest terms the internal lens are organised differently.

This Wikipedia page shows the arrangement of the lens in the different designs fairly well, just about halfway down the page.

For wearing glasses you need an eyepiece that has reasonable eye relief, that means for the shorter focal lengths that plossls and the H, SR etc's are out of consdieration. Suspect the MA's are also.

From the set you link to the 9mm will be little use with glasses, the 12mm may just, and the 15mm should be OK.

For eye relief the standard and budget ended eyepieces that people look at are:

BST Skyguiders,

Celestron X-Cel's,

TMB planetary's.

These supply 15-18mm of eye relief.

[wookie1965]

Like mine ive got skywatcher 150p i bought 32 mm and 18mm and 8mm i may buy a 5mm the limit of my scope. You will find that you will only use 3 or 4 eyepieces and stick with them the rest will just gather dust seems a waste of money buying a set for eyepieces you will use maybe once or twice. My eyepieces Are the BST like Ronin said apart from the 32mm as i wear glasses.

[Jim]

Ok thanks for all the info guys...I guess I should save up a bit more and get the celestron X-Cels...seem to be around 70 pounds each. I will get a 18mm 25mm and 9mm with a Barlow and moon filter.

[wookie1965]

That sounds good you will get a lot of use out of them you will be really pleased with your viewing.

[farunj]

If you get a 2x Barlow, then the 18mm can double up as a 9mm.