Eyepiece advice

[Bobby1970]

o i have my Skywatcher ST102 f5 refractor that came with Skywatcher 20mm and 10mm eyepieces.

I also have my secondhand Skymax 90 that only has a Skywatcher 10mm eyepiece.

I have borrowed a 6mm eyepiece off my dad to try, it has no branding on it at all but seems to work ok but like i say it is only borrowed.

I am going to buy some new eyepieces and wondered which ones would you guys recommend. I mean manufacturer and sizes please.

Probably going to get 2 or 3 if i can find something for £30 to £50 a go. I have read about the BST Explorers but don't seem to be able to find them anywhere, also the Vixen NPL seem to be hightly rated.

I don't know if i should replace the existing 10mm and 20mm or keep them and get some different sizes too.

Finally i wear Specs so could use some decent eye relief.

Any advice is much appreciated.

[j45on]

The chap that sells the BST explorers is on holiday until the 19th of march

items in Sky's the Limit Astro and Optical store on eBay! and http://www.skysthelimit.org.uk/

If that helps

[AWR]

Vixen NPLs are brilliant for the money but the eye-relief on the shorter focal lengths is a bit tight.

TS planetaries (£49) are also worth a look.

Andrew

[Carbon Brush]

Depending on your prescription, you might be better off leaving the specs behind and refocussing the scope.

This would give you more freedom on eyepieces.

There was long discussion about this (I think) last year. I will see if I can find it and post a link.

[gooseholla]

I agree - I don't use glasses with eyepieces but refocus. So much easier.

[Carbon Brush]

I failed to find the thread. But the bottom line is that if you don't have any significant astigmatic correction, then just refocus. Or consider contact lenses?

[Bobby1970]

Thanks for the replies. I have worn specs since i was two yrs old, thats 40 years now. lol. Tried contacts for a few years when i was younger and would rather just put my specs on now tbh. I don't seem to have a problem with eye relief with the 6mm eyepiece i have borrowed but i have no idea what brand it is. Taking my specs off and re-focusing is an option i guess if the eye relief is not satisfactory with my specs on. Surely a decent eyepiece like the ones suggested will give as good eye relief as the no name 6mm one i have been using?

What sizes would you recommend i invest in to use between my scopes. Should i replace the standard ones or stick with them and get some different size better ones?

Thanks again

[Carbon Brush]

Hi Bobby.

Eyepieces are a big and complicated subject. I certainly am at novice level when looking at their characteristics. One thing though. Eye relief on certain designs changes with eyepiece focal length. So if for example you found a 10mm 'supaview' that you liked, so bought the 5mm version, you might well find the eye relief too short. Other eyepeices, for example Baader Hyperion, are designed with fairly consistent eye relief through the range.

Try to have a look through different eyepieces in your scope and see how you get on. A local club night would be good for this.

[Capricorn]

As the ST is around 500mm FL then it may take a 5mm but would be happier with an 8mm.

The 8mm may be usable on a Skymax 90 which is 1250mm so 156x, just not often if at all.

After that say 12mm for both scopes and the 18mm for the Skymax 69x and 28x on the ST.

The values are based on the BST's options available.

The ST being a short Achro will show CA.

The 25mm BST option on the ST would be 20x but would give a 3 degree view which is just enough for all of Andromeda. 50x on the Skymax.

[Bobby1970]

Thanks for the reply.

As i mentioned, i have used a 6mm eyepiece in the SKymax and found it to be ok for planetary work and the moon. So i was looking for something that would give me the same sort of viewing but better quality than the un branded thing i am using.

I am also looking at replacing the standard 10mm skywatcher eyepiece with a Celestron X-Cel 10mm. Do you think this would be a good move?

Then i just wanted something to replace the 6mm i am curerrently using.

[AWR]

If you can stretch your budget then the William Optics SPL 6mm (£69) would be worth a look. I had a look through one last year and thought that it was nicer than my TS planetary (which is still good for £49). The BST explorers get a lot of good reviews on here but I've not used one (nor do I know which lengths they come in). At the cheaper end Vixen NPL plossls (£30) are very good. You wont get the eye relief and only a 50 degree FOV but the clarity is brilliant.

Andrew

[Bobby1970]

I have made a decision and taken the plunge. Ordered a celestron x-cel lx 9mm. And also a 6mm tmb planetary thing.