50mm plossl or finderscope?

[GordonCopestake]

I'm considering selling my 9x50 90 degree finderscope and instead purchasing a very long focal length eyepiece. Something like a 50mm plossl or erfle. With my 600mm scope and a 50mm eyepiece i would get a x12 magnification with a larger than useable 8.3mm exit pupil. The advantage of this over the finder is i can use this eyepiece for wide field viewing as well as finding objects plus given my new grab and go alt az mount i can make do without binoculars too.

What are peoples thoughts on this? A good idea or a bad idea?

[FLO]

A good idea if you have a refractor (other scopes types with a central obstruction might show center darkening when used with a 50mm).

[The Warthog]

Not a bad idea. If you were using the plossl, you would have a FOV of about 4.3° which is comparable to some finders. You might want a red dot finder to get close, though. I have used my 32mm ep as a finder successfully with a smaller FOV.

[Greg]

Gordon..

I use a 40mm Plossl in my refractors for finding stuff and for widefield, a 50mm would be awesome.

But if it's in a Newtonian then some central obstruction would be evident.

[GordonCopestake]

I doubt i'll ever buy another newt hehe, i've been spoiled by APO's

Anyone want to buy a 9x50 right angle finder? hehe

[Greg]

I doubt I'll ever buy another newt hehe, I've been spoiled by APO's

Join the club Gordon.......Should have our own little place on the forum.....Smoking jackets, Cuban cigars, leather wing back chairs, butlers and Fois Gras

[GordonCopestake]

lol i already have my wingback ordered..... my xmas gift from the missus

[The Warthog]

I have some Cuban cigars. Maybe Steve would volunteer to be butler? :pirate:

[Greg]

It's a date ...I'll bring the Fois Gras...

Toast or crackers?

Steve....Don't be late ...One cant abide tardiness 8)

[John]

Gordon,

If you eventually sell your RA finder I'd definately be interested.

John,

North Somerset

[FLO]

Should have our own little place on the forum.....Smoking jackets, Cuban cigars, leather wing back chairs, butlers and Fois Gras

Maybe Steve would volunteer to be butler? :pirate:

Steve....Don't be late ...One cant abide tardiness 8)

I don't own an APO

..... oh, I get it, thats why I'm the butler! Snobs!!

[GordonCopestake]

Gordon,

If you eventually sell your RA finder I'd definately be interested.

John,

North Somerset

i'll PM you

[GordonCopestake]

Snapped up a 40mm plossl from Astro buy/sell. I'll let you know how i get on

[FLO]

Something to consider when choosing a 'finder' eyepiece:

Along with magnification, consider also the eyepiece FOV. For example, Meades SWA 24mm with a 68º apparent FOV covers roughly the same amount of sky as their 32mm Super Plossl.

This image (created using StarryNight PRO) shows it well:

Green circle - 24mm SWA

Yellow circle - 32 Super Plossl

[GordonCopestake]

Steve, can you do me a M31 with a 52 degree 40mm plossl on the 80/600 ed80?

[GazOC]

If its an 1.25 EP it'll be the same as the 32mm Super Plossel.

[GordonCopestake]

true

[FLO]

Yes,

Though the (1.25 fitting) 40mm has its uses (for camera-to-eyepiece imaging) the 32mm is the better buy.

I'll post an image in a mo'

[GordonCopestake]

Well for £18 off astro buy/sell im not going to complain heh

[FLO]

Done

The Meade 40mm SP should deliver (actually visible) 43º and the 32mm 49º.

StarryNight shows a small difference:

[GordonCopestake]

Thanks Steve! I'm happy with that FOV

[FLO]

I have been playing

#

[GazOC]

Thats a lot of difference between the 2" 40mm and the 1.25" format.