Can I use a 2" eyepiece on a 1.25" scope?

[LittleSkink]

One day I might get that 200P I have dreamed of but right now have a basic 1.25" focusser on a 100P. Been offered a 2" Eyepiece (not a 2" / 1.25" dual fitting like some mid priced lenses) for a silly price - but I assume it simply wont fit?

[Dave In Vermont]

No it would not fit. 2 inches is 2 inches - and you can't fit anything larger than your 1.25 inch focal draw-tube. You can fit 1.25" into a 2" with an adaptor.

Clear Skies,

Dave

[LittleSkink]

thanks Dave, that's what I thought but good to know for sure

[Moonshane]

You can actually. I have seen a 1 25 - 2" adapter but you would lose some field depending on the field stop size. Will try and find one.

[Moonshane]

http://agenaastro.com/blue-fireball-1-25-2-eyepiece-adapter.html

[Moonshane]

That said I'd buy a 32mm plossl.

[Dave In Vermont]

At least the ad admits vignetting may be a problem. I'll say! LOL!

I'll go along with the 32mm Plossl, too.

Clear & Un-Squashed Skies,

Dave

[John]

Apart from the vignetting, the additional focuser travel that the adapter requires could well create problems for the 100P scope.

Incidentally, the eyepieces that have a dual 2" / 1.25" fitting are 1.25" eyepieces. They don't become 2" eyepieces when you use their 2" barrels, it's just a convenience feature. The Baader Aspheric 31mm and 36mm eyepieces are 2" eyepieces that come with a 1.25" barrel option but the field of view of the eyepieces reduces when you use those barrels.

Another vote for a 32mm plossl here, or a 24mm 68 degree eyepiece if you come across one at a decent price.

[LukeSkywatcher]

I'll add my vote to a 32mm Plossl. The 32mm GSO is simply a fantastic eyepiece and sells for about 30-40 quid. There are others, but this one i fell in love with. Worked great for me on a 90mm,130mm scope.

[avtaram]

There's a Maxvision 24mm 68* for sale in the classified section.

Avtar

[Moonshane]

Even better