eyepieces Help?

Celestron claim a maximum useful power of 480x for the C8N (a factor of 2.4x objective) but we almost never get that kind of weather. 225x seems to be the average highest power that most Irish astronomers expect to be able to use with 8" instruments. Your 12mm gives 83x, the 20mm gives 50x and the 12mm with Barlow 167x.

I would suggest using the 12mm and Barlow for high power initially and adding a 32mm eyepiece to your collection first. Giving 31x, that would provide pleasing low power views of the Moon and large Messier objects. Then get a 5mm (200x) or 6mm (167x) for planetary viewing and general high power instead of using the Barlow, and if you find after using it for a while that you'd like to be able to split the difference in magnification between that and the 12mm consider an 8mm (125x) to accompany a 5mm or a 9mm (111x) if your high power choice was a 6mm. For anything shorter than the 12mm choose long eye relief eyepieces for comfortable viewing.

Personally I have a large collection of eyepieces because I have several telescopes of different focal ratios (f/5, f/6.8, f/10 and f/13). But I have never used more than 5 eyepieces on the same night with a given scope. For one telescope start with a few well chosen, good quality eyepieces and you'll save money in the long run.

I agree with David Branigan on the subject of 2x Barlows. With good eyepieces a barlowed one is seldom as good as one of half the focal length (or thereabouts). I only use my 2x Barlow for occasional imaging now and if I had one would never consider using a 3x Barlow with an eyepiece.

Like the guys sat above, barlows might seem like a cheap and great way of doubling your eyepiece collection, but it doesn't work out that way. I have a 2x and 3x barlow and use them for planetary imaging only.
The big draw back with a 6mm eyepiece is the eye relief, you have to get your eye really close up to the eyepiece to see through it.

50 degrees seems abit small, the meades 4000s are 55degrees and there are many good cheap second-hand ones on the web. I'd get a 30+mm eyepiece and a 6-8 mm, I guarantee you that you will not use the 6-8mm eyepiece as often as you might think.
If cost isn't an issue, then get Naglers, they are the Ferrari's of the eyepiece world.

Ok, thanks guys, I won't get the Ferrari's just yet, better to get rid of my Learner sign first! So, I think I will get just 2 more eyepieces at either end, focal length, There are some available on ebay, but to be honest I wouldn't know if I am buying a dud or not, so I think I would prefer a "proper" online shop... www.telescope-service.com seems to be quite good, I was thinking of something like this: A TS Super Plossl 32mm - fully multi-coated 52° @ Euro 49.- & a Planetary HR Eyepiece, 5mm, eye relief, 16mm @ Euro 89.- Does this sound reasonable? Don't forget I only half know what I am talking about. Thanks!

Rayman,
Please take what I say with a large dose of salt as I too am a newbie and really don't know what I'm talking about.

1. TS 32mm I have one of these and am very pleased with it, with your telescope it should yield you a magnification of x31 and generous 1.65 degree field of view.

2. 5mm Planetery HR eyepiece,Telescope Services say this is designed by Tom M Black in which case they should be superb. It looks similar to the Burgess/TMB eyepieces reviewed on Cloudy Nights (Its under CN Reports/Eyepiece reports) however this report doesn't mention a 5mm version. With this eyepiece you'll have mag x200 with 0.3 degree field of view. One drawback with this eyepiece is that you won't really be able to barlow it.

I'd suggest you look at getting a wide angle lens, I got a TS 15mm WA and it didn't cost a lot but is my favourite lens at present.

Ok thanks Martin, I am certain of the two new lenses now (I think). The options are confusing, but I supose all new hoppies are until you get the hang of them. I will have a look into the wide angle lens too. Thanks again all.

I'll second Martin's recommendation of the 5mm TMB Planetary.

After a time I'd also recommend replacing your 20mm and 12mm Ploessls with the Hyperion 21mm and 13mm eyepieces for significantly wider fields of view.

The TS 32mm and TMB Planetary eyepieces recommended by Martin are both available at fair prices from www.telescope-service.com , I've purchased a number of items from them and find that my Euro goes further than it does locally or in the UK. The staff are knowledgeable, the service is excellent and they carry a much wider range of product lines (ranging from very affordable to high quality) than some of the brand-specific outlets both here and in the UK. I don't think either of the multi-brand dealers here in Ireland carry either eyepiece range.