Need advice on new eyepieces

[coxie]

Hi chaps, I recently got my 1st scope the SW explorer 130p az goto, i have only been able to get it out 2 or 3 times due to the poor weather over the past few weeks. I was wondering if any one here would have some advice and possibly links to a good new eyepiece or 2 which is a better eyepiece than the 10mm i have already which came with the scope, i would like to be able to see the moon at a slight bit higher magnifications than I can at the moment, also I have the 2x barlow should I stick with that or possibly get another? If you could provide me a link aswell because I am not sure which eyepiece would fit my scope its 1.25"

[TopHouse]

I've got the 200p and after doing a lot of homework i bought the baader hyperion 8mm along with the 2 adjustment rings which in effect gives me 4 sizes 8mm, 6mm, 5mm and 4.3mm. I'm really really happy with it, but you may not want to spend that much on one.

[orionhunter]

ive got the SW 150p, and ive had expert advice that the most suitable 3 x EPs are a 40mm/20mm/10mm. (most used).

any others are nice to have, but will hardly be used.

im not 100% sure if the same thing applies to your scope?

[John]

I would not use a 40mm in an F/5 scope - 32mm is the optimum before the exit pupil gets overlarge. Also, in the 1.25" fitting, the max field of view of a 40mm is the same as a 32mm due to the constraints of the barrel size - so you see the same amount of sky with the 32mm.

[TopHouse]

Think I'd be reconsidering that 'expert advice' orionhunter (I'd have suggested a 32 as well for wide)

[coxie]

FLO recommended a 7.5mm Skywatcher SP Plossl eyepiece but does that sound right? just fishing for the general vibe from you guys too because i value all of your opinions.

[david o]

Hi coxie,

This sticky has some good advice for choosing EPs:

Eyepieces - the very least you need.

[John]

FLO recommended a 7.5mm Skywatcher SP Plossl eyepiece but does that sound right? just fishing for the general vibe from you guys too because i value all of your opinions.

I reckon, on it's own and used in combination with your 2x barlow a 7.5mm makes a lot of sense - 87x and 174x - very useful powers with a 130mm scope. The Skywatcher plossls are a good deal for £20 apiece I think.

[TopHouse]

I'm really pleased with myself now as I suggested the 8mm hyperion, I love mine, after playing about with other eyepieces both what came with the scope and in the antares set I bought, the hyperion with it's tuning rings were what really did mars for me. I was over the moon so to speak. Being a glasses wearer too it suits me even better. LOVE my hyperion.

[coxie]

thanks for the help so far people, would like to hear from a few more experts before i consider it in more depth, its probably more for seeing the planets and the moon what im after in more detail

[pvaz]

On the focal length I think the advice on the 7.5 to add to the 25 and 10 you already have is a good idea.

The problem with eyepieces is the huge offer out there. You can get a 7.5mm plossl for 20£ or an 8mm Ethos for around 450£. It depends on more things then just the magnification you'll obtain. There are other parameters such as the width of the field of view (FOV), light transmission, contrast, edge correction and eye relief (distance you can have your eye from the EP to see the image). Maybe more I can't remember now...

So here are some points to think about:

- Plossl design probably gets you the cheapest EP with a decent quality in all parameters. The FOV is wide enough, well corrected, the major problem is eye relief (in case you wear glasses it may be impossible to use them while observing).

- On contrast, light transmission and sharpness, which are very important for planets, the cheapest great performer you can get is an Orthoscopic design EP. Orthos have a tiny FOV and very small eye relief (again not good if you wear glasses). The University Optics Orthos are great and cost around 50£.

- If instead you want a wide FOV, a decent eye relief and still very good light transmission/contrast you can get something like a Baader Hyperion, a William Optics SPL, a Skywatcher Nirvana... and so on. In very accurate tests these will loose to the best Orthos in the light transmission and contrast department as they use much more glass elements to provide the other comforts, but the difference should be hard to notice visually (at least with the more expensive ones). They do cost more.

Going to a star party or a local club meating and actually look through some of this may help you a lot in your decision.

[coxie]

thanks pvaz