T3D Re: Telescope eyepieces (Was: Now yer in trouble)

[John Ohrt <johrt@xxxxxxx>]

Greg Erker wrote:

>   Are you saying that telescope eyepieces make
> good 2d/3d viewer lenses?

I am saying that I agree that amateur telescopr eyepieces are aally good
source of viewer lenses.  The users are quite critical of optical
quality and the cost/effectiveness ratio is likely consistant with 3d
requirements.  If they are good enough, I don't know of a cheaper
alternative.


> What size image will they cover?

That is easily calculated given the focal length in mm and apparent fov
in degrees.

The formula is:

field diameter = focal length *2* tan (fov/2)

eg a 40 mm focal length with a 50 degree field of view

field diameter = 40 * 2 * tan(25) = 80*.47 = 38 mm

John B. to confirm the above.  Also trying to define the crieria to
determine the fov is a well discussed item on this list!

>Or are you using them for something else?

I use them only as telescope eyepieces!

Regards,

--
John Ohrt,
Toronto * Ontario * Canada



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