Yet another EP question, plossl`s

[nightfisher]

Next year i might well save for a single higher price EP for lunar viewing, i own GSO plossl`s and a couple of circle T ortho`s at present, so im thinking maybe get an EP at about £100, purely for lunar viewing, what would be the suggestions please, i dont wear specs and i have long focal length scopes...D100 F10 and D180 F15:icon_scratch:

[E621Keith]

May be a BGO

[nightfisher]

Thats one idea, not sure what size to go for due to the 2 different scopes, a 15mm ep in the mak would be ideal, maybe ok for the tal, so many choices

[E621Keith]

What are the focal lengths of your existing eyepieces? May be there is a gap waiting to be filled

[AndyH]

Mmmm.

Two very different FL's.

For the moon, I like a range between about 120x to 200x.

FL 1000 = 8 to 5mm eyepiece

FL 2700 = 22 to 13mm eyepiece

Mmm. Tough one. Thought of getting(unless you already have one), a 2x or 3x barlow?

Then a 13-15mm eyepiece, or thereabouts, might be the way to go?

Andy.

[nightfisher]

cheers andy, dont like using barlows as it introduce`s more glass into the optical train, sort of toying with a baader hyperion and a fine tuning ring, in a perfect world i would get a 9mm BGO for the tal and an 18mm BGO for the 180, but thats pushing the budget to high

[AndyH]

Yup.

I'm not a user of barlows either.

Don't discount the std volcano topped orthos. Whilst many folk say the flat tops give an improved view, I used to have full sets of both types and saw minimal if any difference/improvement. I actually prefer the volcano's at the shorter focal lengths, because of their shape. More comfortable to use IMHO.

Cheers,

Andy.

[E621Keith]

I just read the CN report on 6mm planetary eyepieces.

http://www.cloudynights.com/documents/planetaryeyepieces.pdf

It mentioned Edmund Optics RKE is a good performer for planets. They are about £60 each (ex shipping), so a bit cheaper than BGOs. Edmund Optics RKE Precision Eyepieces

I have no experience with this eyepiece, in fact I have only heard of it once before. May be someone else can comment on the RKE.

[Adz]

A couple of second hand orthos in the two mags mentioned sounds like a good idea.

[A McEwan]

Well, back when I had the 180 Mak, I found the BGO 12.5mm to be the best performer for me on Jupiter, giving 216x. That in the Tal 100 would only give 80x. A good Barlow would be the answer, and I'd not hesitate to recommend either the Celestron Ultima 2x or the Revelation 2" 2xED - both simply disappear in use.

The old argument about 2Barlows in the optical train...more glass... etc" I think is outmoded now. Optical coatings and design have come on so far that I think it would take an excellent eye under perfect seeing to spot a noticable difference between a Barlowed view and a native short fl one.

Plus, a Barlow will retain the easy eye relief on a mid-focal-length eyepiece, making that 12.5mm BGO a slightly more comfortable option in the Tal than a 6mm or 7mm.

Ant

[nightfisher]

well its looking like i might opt for the 18mm BGO and use my tal x2 barlow for using it in the tal100, i already have a 12.5 circle T ortho, the 18mm BGO could be usefull for A-focal lunar work as well

[Adz]

They are great and definitely the most comfortable of the set