## What is the formula for magnification of a telescope?

M = fo / fe , where: M is the magnification of the image. fo is the focal length of the objective (sometimes referred to the telescope focal length).

### What magnification is 10mm?

A short focal length 10mm (high power) eyepiece used on the same 1000mm telescope will produce a magnification of 1000 ÷ 10 = 100x.

**What is eyepiece magnification?**

Magnification increases, therefore, when the focal length of the eyepiece is shorter or the focal length of the objective is longer. For example, a 25 mm eyepiece in a telescope with a 1200 mm focal length would magnify objects 48 times. A 4 mm eyepiece in the same telescope would magnify 300 times.

**How do you calculate Barlow magnification?**

A Barlow functions by effectively increasing the focal length of the telescope, and thereby its magnification with any given eyepiece. For example, if you use the Ultrascopic 30mm eyepiece in a telescope of 1,200mm focal length, the combination provides 40X magnification (1,200/30=40).

## Which is stronger 10mm or 20mm?

Simply divide your telescope’s focal length by your eyepiece focal length to get your magnification. Therefore, a 10mm is twice as powerful as a 20mm.

### Is 10mm or 20mm eyepiece better?

The most important eyepiece characteristic is focal length. This means that a smaller number on an eyepiece gives a higher magnification. A 10mm eyepiece would provide twice as much magnification as a 20mm eyepiece. It also means that the same eyepiece gives different magnifications on different scopes.

**Which is bigger 10mm or 20mm?**

**What MM is a telescope eyepiece?**

Usually, you’ll want to start with low power (i.e., long eyepiece focal length, such as 25 mm or 30 mm) to get the object in the field of view of the telescope. Then you might want to try a slightly higher-power (shorter focal length, maybe 18 mm or 15 mm) eyepiece and see if the view looks any better.

## How do you calculate telescope magnification with a Barlow lens?

### Is a 2x or 3x Barlow lens better?

To put it simply, Barlow lenses are a cost-effective way to increase the magnification of your eyepieces. Their effect is to increase the magnification of any eyepiece used with them, usually 2 or 3 times. As you’d expect, a 2x Barlow doubles your eyepiece magnification, whilst a 3x trebles it.

**How does the telescope and eyepiece affect the magnification?**

So the telescope and eyepiece affect the magnification in different ways: Telescopes with longer focal lengths will give a higher magnification (for a given eyepiece) Eyepieces with shorter focal lengths will give a higher magnification (for a given telescope)

**What is the magnification of the image seen in the eyepiece?**

Example: Your telescope FL is 1000 mm and your eyepiece FL is 20 mm. 1000/20= 50x! The image seen in your eyepiece is magnified 50 times! Being able to quickly calculate the magnification is ideal because it gives you a more:

## What is the magnification of my Telescope?

The magnification formula is quite simple: Example: Your telescope FL is 1000 mm and your eyepiece FL is 20 mm. 1000/20= 50x! The image seen in your eyepiece is magnified 50 times! Being able to quickly calculate the magnification is ideal because it gives you a more:

### What is the difference between a 10mm and 1200mm telescope?

As you can see, the 1200mm telescope gives a higher magnification with these eyepieces – and the 10mm eyepiece gives a higher magnification with both telescopes. So the telescope and eyepiece affect the magnification in different ways: Telescopes with longer focal lengths will give a higher magnification (for a given eyepiece)