Eyepiece Lens

Matching Eyepiece Telescope Lens For Maximum Viewing

Most quality telescopes require the use of an eyepiece as part of the magnification power of the telescope. If you have a telescope with a single eyepiece, you will want to investigate using one or two different ones for different purposes. The eyepiece telescope has this advantage of those that do not have a changeable eyepiece.

The eyepiece plays a major role in the magnification power of an eyepiece telescope. In order to calculate what the magnification would be with a different eyepiece you would divide the focal length by the eyepiece focal length. Since the focal length of an eyepiece telescope will remain constant, by changing the eyepiece you can change the power.

Not everyone changes an eyepiece to increase the magnification, especially if wanting to view areas that are closer or they want a wider field of view. One reason to reduce the magnification may be to create a finder lens for your telescope to be able to find an object. With a strong eyepiece telescope, finding the moon through the normal magnification could be like trying to find it while looking through a straw.

Effective Fields Of View Also Changes

The true field of view, that is what you can see as an undistorted image can also be adjusted by changing the eyepiece on an eyepiece telescope. The field stop on an eyepiece is the rotating ring that limits the field size. To find the true field of view, divide the field stop diameter by the telescope's focal length and then multiply by 57.3.

In order to obtain lower power viewing of large objects your eyepiece should deliver the widest possible field of view. A one and a quarter inch eyepiece would have a field stop of 27mm maximum. The maximum field stop on a two-inch eyepiece is about 46 mm.

A general rule of thumb with an eyepiece telescope is that choosing an eyepiece with shorter focal lengths and larger apparent field of view, bringing brighter, clearer images of objects including fainter stars.

Two things to consider when looking at news eyepieces could be a Barlow lens, which simply is a magnifier, which adds magnification power to the eyepiece telescope, and what is called eye relief.

Eye relief is the space between the lens and your eye and should have enough room for you to be able to wear your glasses, if needed, as well as to keep your eyelashes from brushing against the lens.

About the Author

Ann Marier has written many articles on
health questions
providing helpful tips and advice. Read all about her latest articles on telescopes and how to use a
child telescope
to generate their interest in the universe

If you want to place the eyepiece so that the image it produces is at infinity, how far should this lens be fr

An insect 1.20 mm tall is placed 1.00 mm beyond the focal point of the objective lens of a compound microscope. The objective lens has a focal length of 12.0 mm, the eyepiece a focal length of 25.0 mm.

If you want to place the eyepiece so that the image it produces is at infinity, how far should this lens be from the image produced by the objective lens?

Let x be the required distance in mm.

1 / 13.0 + 1 / v = 1 / 12.0
v = 156 mm.

The image from the objective needs to be at the focus of the eyepiece to produce a final virtual image at infinity.

1 / (156 - x) = 1 / 25.0
x = 156 - 25
= 131 mm.

Long Range Hits




Bushnell 2x Barlow Lens for Eyepiece with 125 Diameter 780105
Bushnell 2x Barlow Lens for Eyepiece with 125 Diameter 780105

$9.99
14d 22h 42m remaining

125 Ultra Wide Angle Eyepiece Lens 6mm 66 Deg Multi coated For Telescopes US
125 Ultra Wide Angle Eyepiece Lens 6mm 66 Deg Multi coated For Telescopes US

$21.15
26d 17h 58m remaining

Tele Vue 19mm Panoptic Telescope 1 1 4 Eyepiece Lens
Tele Vue 19mm Panoptic Telescope 1 1 4 Eyepiece Lens

$142.50 (5 Bids)
1d 10h 33m remaining

SVBONY 125 317mm Barlow Lens2X Telescope Eyepiece Astronomy T Adapter US
SVBONY 125 317mm Barlow Lens2X Telescope Eyepiece Astronomy T Adapter US

$12.84
28d 13h 52m remaining

SVBONY SV136 Barlow Lens3X 125 Multi coated Metal for Telescope Eyepiece
SVBONY SV136 Barlow Lens3X 125 Multi coated Metal for Telescope Eyepiece

$21.15
18d 17h 34m remaining

33MM lenses for telescope eyepiece or experiments lens
33MM lenses for telescope eyepiece or experiments lens

$3.95
8d 6h 48m remaining

Orion Stratus 68 degree Eyepiece 35mm
Orion Stratus 68 degree Eyepiece 35mm

$109.99
28d 6h 20m remaining

SVBONY 125 Astro elescope Eyepieces Kit Set Eye Lens 66 Ultra Wide Angle US
SVBONY 125 Astro elescope Eyepieces Kit Set Eye Lens 66 Ultra Wide Angle US

$73.59
16d 18h 14m remaining

125 Plossl Telescope Eyepiece Set 4 10 25mm+Barlow Lens Kit For Astronomy US
125 Plossl Telescope Eyepiece Set 4 10 25mm+Barlow Lens Kit For Astronomy US

$36.79
14d 17h 12m remaining

SVBONY Relief Eyepiece 15mm 12568Ultra Wide Angle Lens for Astro Telescope US
SVBONY Relief Eyepiece 15mm 12568Ultra Wide Angle Lens for Astro Telescope US

$24.83
11d 13h 21m remaining

Meade Super Wide Angle 245mm Multi Coated Telescope 1 1 4 Eyepiece Lens
Meade Super Wide Angle 245mm Multi Coated Telescope 1 1 4 Eyepiece Lens

$99.95
1d 10h 28m remaining

2 inch 32mm Wide Field Super Plossl Telescope Eyepiece NEW XL lenses
2 inch 32mm Wide Field Super Plossl Telescope Eyepiece NEW XL lenses

$48.77
19d 17h remaining



« Previous12345...89


Tagged with:

Filed under: Eyepieces & Accessories