2" or 1.25" Eyepiece

[jasperuk]

If is had both a 2" and 1.25" eye piece made by the same company and the same (mm sizing) what differences would i notice ???

Basically is there any advantage to 2" as apposed to 1.25"

Ta

[pajr777]

I wondered this too. My focuser takes both 1.25" and 2", and my Baader Hyperion Zoom MkIII comes with both 1.25" and 2" nosepieces.

Is there any advantage to using 2"? I've stuck with 1.25" simply because my Barlow is 1.25"..

[swamp thing]

Hi

Have you had a read of this.?

http://stargazerslounge.com/primers-tutorials/63184-primer-understanding-choosing-eyepieces.html

Basically if a company made two 20mm 50deg AFOV plossls one in 1.25" and one at 2" the view through each would be the same.

[John]

The only advantage the 2" format gives is the ability to deliver wider angles of view, eg: if you want a 32mm eyepiece that has, say, a 70 degree field of view, then it will need to be in the 2" format. The 1.25" size restricts the max field of view and in the case of a 32mm focal length eyepiece, 52 degrees is the limit.

The Hyperion zoom is a 1.25" format eyepiece that comes with a 2" barrel as a convenience. Using it does not turn the zoom into a 2" eyepiece.

[E621Keith]

The only advantage the 2" format gives is the ability to deliver wider angles of view

I don't agree. The 2" format also gives a much stronger mechanical connection. This is particularly important for heavy eyepieces and accessories.

[John]

I don't agree. The 2" format also gives a much stronger mechanical connection. This is particularly important for heavy eyepieces and accessories.

Thats a fair point Keith and I should have included it in my post

Even though the Hyperion Zoom is a 1.25" eyepiece, it's a chunky one and many will find using it in a 2" drawtube / diagonal feels more secure.