The eyepiece of a telescope is the place where you look into. It can be located on one end of a telescope or possibly on the side of a telescope depending on the type of telescope.

These next two pictures show the location of the eyepiece.

If you need to buy one of these eyepieces there are two major things to consider. The first thing is the width of the eyepiece and the second thing is the magnification of the eyepiece.

The width of the eyepiece. This is typically given in inches and there are three major sizes. They are .965" , 1.25" and 2".

To know which diameter eyepiece you need all you have to do is measure the opening in the telescope eyepiece holder. Mine here is 1.25 inches.

This is the most common size of eyepieces.

So, now you know the diameter of your eyepiece. Just one more thing you need to know. What is the size of the lens you need? Well, lenses don't come in particular magnifications. This is the nature of the optics. They do come in focal lengths and diameters and this is important because the different focal length of eyepiece lenses will give you a different magnification with your telescope.

That might be a bit confusing but let me explain it very easily. Eyepieces are very clearly advertised and marked with their focal length. And it is in mm. Remember how the width of the eyepiece is in inches? Well, the focal length is in mm. That makes it easy. And most eyepieces are between 4mm and 28 mm.

And..... The bigger the number the lower the magnification. So.. if we had a 4mm eyepiece and a 28mm eyepiece the 4mm is the "more powerful". It magnifies more.

So here are two of my eyepieces:

Can you say which one will give your telescope the higher magnification?

It is the 10mm. Remember, the shorter the focal length the higher the magnification.

Ok, so what should you buy for your telescope? The highest power?

Nope, probably not. The thing about telescopes is that they magnify! LOL! I know that sounds funny. Of course they magnify. But.... they also magnify problems, vibrations and atmospheric conditions. And the higher the magnification the more difficult it is to get glass curved accurately without distorting the image.

So, you really don't want high "power" in your telescope. You want low power. This creates the best views with the sharpest detail. Higher magnifications create poor images.

What eyepiece do you get? Get something between the 10 and 20mm that you see in the picture. And lean toward the 20mm. That would probably be your best bet. And if you can afford two of them then get one around each number.

Here are some eyepieces available on amazon:

I like this next set. A little bit more than average power, two eyepieces, filters and even a cleaning cloth. And celestron is a quality company.

Celestron Powerseeker Accessory Kit - (1.25" diameter eyepieces)

• 15 mm Kellner Eyepiece.
• 9 mm Kellner Eyepiece.
• #80A Blue Planetary Filter.#25 Red Planetary Filter. Moon Filter. Micro Fiber Cloth.Plastic Carrying Case with Foam
• Fully-coated eyepieces for higher magnification.Planetary filters enhance details on Jupiter, Saturn, Mars and Venus
• Moon filter allows detailed views of the Moon especially during the brighter phases
• Carrying case fits all of the included items in the die-cut foam interior
• Micro fiber cloth safely cleans optics without scratching or leaving residue

12.5mm Plossl eyepiece (1.25" diameter)

• Threaded for standard 1.25- inch astronomy filters and barlow lens.
• Fully multi-coated lenses, 4 lens elements, Blackened lens edges
• 1.25- inch 12.5mm plossl eyepiece set , gives the widest viewing field along with extra sharpness and long eye relief.
• 4-element plossl design, has a approx 52 degree AFOV. Perfect for broad-field lunar observations, medium-sized star clusters, and a wide range of cloudy nebulas and deep-sky targets.
• Fold-down rubber eyeguard Threaded for standard 1.25- inch astronomy filters.

20mm Plossl eyepiece (1.25" diameter)

• 1.25 inch 20mm plossl eyepiece, gives the widest viewing field along with extra sharpness and long eye relief
• 4-element plossl design, has a approx 52 degree AFOV. Perfect for broad-field lunar observations, medium-sized star clusters, and a wide range of cloudy nebulas and deep-sky targets
• Comes with sturdy plastic case-proect the eyepiece from dust and moisture
• Threaded for standard 1.25inch astronomy filters and barlow lens

6, 12.5 and 20mm Plossl Eyepieces -

This is a very nice medium power eyepiece set . 1.25 inch 6mm, 12.5mm , 20mm plossl eyepiece set , gives the widest viewing field along with extra sharpness and long eye relief. 4-element plossl design, has a approx 52 degree AFOV. Perfect for broad-field lunar observations, medium-sized star clusters, and a wide range of cloudy nebulas and deep-sky targets. Comes with sturdy plastic case-proect the eyepiece from dust and moisture. Soft rubber eye guard that's custom fitted with a bayonet mount. Threaded for standard 1.25inch astronomy filters and barlow lens

Lots More Eyepieces on Amazon right here

Try my book. I specifically wrote it to help you enjoy your small telescope.

See It with a Small Telescope: 101 Cosmic Wonders Including Planets, Moons, Comets, Galaxies, Nebulae, Star Clusters and More - Available in paperback and kindle on Amazon right here

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