14mm or 18mm Radian For An ED80?

[DeejayP999]

Hi all,

I'm looking for an low-mid power EP to give around a 2mm Exit Pupil with my ED80. I currently fill this spot with a cheap 17mm Plossl - but I'm looking to improve on that. I already own several Televue Radians and it's an EP that I particularly like. Sadly, there's no 17mm in the range so it's a shootout between the 14mm and 18mm.

It strikes me that with the larger FOV of the Radians I could fit in the same objects at higher mag, but I worry about dimming the image with a smaller exit pupil...

So do I go for the 14mm (slightly more mag, slightly smaller exit pupil, same FOV as my Plossl) or the 18mm (similar mag & exit pupil, larger FOV)?

What d'ya reckon?

[pbyrne]

If you already use a 17mm Plossl and were happy with that go for the 18mm. I have an 18mm myself and find it a wonderful eyepiece in the dob.

Is the focal length of the scope 600mm? If so then the 14mm will give a magnification of x43 and the 18mm x33. The 18mm will give some really nice wide field views.

What other Radians do you own, perhaps the 14mm is too close to another Radian you own and the 18mm suits better.

[Moonshane]

I'm kinda in the same boat but wishing there was a 16mm Radian.

Probably for Christmas!!, I'm considering a 16mm T5 Nagler or possibly a 16mm WO UWAN/SW Nirvana.

I really love both my 14mm Radian and my 18mm as they give a great range, especially with the Powermate too. I actually don't see a great deal of dimming with the 14mm when used alone cf the 18mm so I wouldn't let that concern you.

if you are near Manchester, feel free to bring your scope along and you can try mine. (I can also see what it's like to compare your 80mm ED with my 120mm Achro!).

[DeejayP999]

Chaps, thanks for the replies!

Sadly, I'm nowhere near Manchester (I'm in Surrey) otherwise I'd love to compare scopes.

Currently I own the 8mm and 10mm Radians. In truth, I don't use the 10mm much, but the 8mm hits a real sweet spot with my scope.

I'm currently looking at the "3 for the price of 2" deal on Radians with a view to buying the 5 and 6mm and one other (hence my question).

[Moonshane]

no worries mate and good luck with the decision - whichever you choose will be excellent.

[pbyrne]

Seeing as you don't use it would you not consider selling the 10mm and use the cash towards that purchase?