How to increase the magnification of the telescope

The magnification

 The magnification of a telescope is an important factor in determining its capabilities. Many telescopes come with a fixed magnification but with a few modifications to your setup, you can significantly increase it and get a closer look at the stars.

Key considerations

Method of Increasing MagnificationDescriptionConsiderations and Tips
Changing EyepiecesUsing eyepieces with shorter focal lengths.Provides a simple and cost-effective way to increase magnification.
Using a Barlow LensA lens that multiplies the telescope’s magnification.Typically doubles or triples magnification; compatible with existing eyepieces.
Opting for a Zoom EyepieceAn eyepiece that offers a range of focal lengths.Offers flexibility but may have lower optical quality compared to fixed focal length eyepieces.
Upgrading TelescopeInvesting in a telescope with a longer focal length.Higher cost but results in better magnification and image quality.
Atmospheric ConditionsConsidering the impact of atmospheric turbulence.High magnification can be limited by atmospheric conditions, leading to image distortion.
Telescope ApertureUnderstanding the role of aperture in magnification.Larger apertures provide brighter images at higher magnifications.


The first step in increasing the magnification of your commercial telescope is to purchase additional eyepieces. The eyepiece is the lens that you look through to observe the objects in the sky. By adding a higher-magnification eyepiece to your setup, you can increase the overall magnification of your telescope. Note that the magnification is determined by the focal length divided by the focal length of the eyepiece. Therefore, by using a higher-magnification eyepiece, you can increase the magnification of your telescope.

Sizes and focal lengths

Sizes and focal lengths-How to increase the magnification of the telescope
Most important eye piece diameters in amateur astronomy: 2 inch, 1 1/4 inch and 0.96 inch

Eyepieces come in various sizes and focal lengths, and each one provides a different magnification level. The magnification of a telescope is determined by dividing the focal length of the objective lens by the focal length of the eyepiece. Therefore, by changing the eyepiece, you can change the magnification of your telescope.

For example, a 25mm eyepiece with a 1,000mm focal length telescope will provide a magnification of 40x. However, if you switch to a 10mm eyepiece, the magnification increases to 100x. It’s important to note that higher magnification does not always result in better image quality. Magnification levels must be chosen based on the specific celestial object you’re observing. The atmospheric conditions, and the quality of your telescope. Higher magnification levels may not be useful on poor atmospheric conditions or for observing bright objects.

Flexibility and convenience

Additional eyepieces provide flexibility and convenience for astronomers. By having a range of eyepieces, you can quickly switch between magnification levels without having to spend time adjusting the telescope’s focus or adding/removing other equipment. This can save time and allow you to observe multiple celestial objects in one observing session. The quality of additional eyepieces is also critical.

A low-quality eyepiece can negatively impact the image quality, and in some cases, result in distorted or blurry images. Investing in high-quality eyepieces can provide sharper, clearer, and brighter images, enhancing your observing experience. It’s important to consider your observing goals when purchasing additional eyepieces. Different celestial objects require varying magnification levels. For example, observing a nebula may require lower magnification levels, while observing planets may require higher magnification levels.

Barlow lens

Another way to increase the magnification of your commercial telescope is to add a Barlow lens to your setup. It is a type of lens that, when used in combination with an existing telescope eyepiece, can effectively double or even triple the magnification of the image seen through the eyepiece. The Barlow lens was first developed in the mid-19th century by Peter Barlow, a British mathematician and physicist. The purpose of the Barlow lens was to provide an alternative to the more cumbersome and expensive methods of increasing telescope magnification, such as adding longer focal length eyepieces or using larger mirrors. With the Barlow lens, amateur astronomers could achieve higher magnifications with the equipment they already owned.

Barlow lens
Barlow lens

The Barlow lens is essentially a diverging lens that is placed between the eyepiece and the telescope’s focal point. When light passes through the Barlow lens, it diverges and spreads out, effectively “stretching” the light cone that enters the eyepiece. This results in an increase in the magnification of the image that is seen through the eyepiece.

Types of Barlow lenses

There are different types of Barlow lenses available on the market. They range from simple single-element designs to more complex multi-element designs that provide higher image quality. However, even the simplest Barlow lens can significantly increase the magnification of a telescope. Making it a valuable accessory for amateur astronomers.

One of the key advantages of the Barlow lens is its versatility. It can be used with any telescope eyepiece, allowing amateur astronomers to experiment with different magnifications and fields of view. This makes it an ideal tool for exploring different celestial objects, from the moon to nebulae. Another advantage of the Barlow lens is that it allows for higher magnification without sacrificing image quality. When using longer focal length eyepieces, the image can become dimmer and lose sharpness. With the Barlow lens, the image remains bright and clear, even at higher magnifications.

However, it is important to note that using a Barlow lens can also have its limitations. Increasing magnification beyond a certain point can result in a loss of image quality due to atmospheric distortion, poor seeing conditions, or limitations of the telescope itself. It is also important to ensure that the Barlow lens is compatible with the eyepiece and telescope being used, as not all combinations will work effectively.


To increase the magnification of your commercial telescope you can add a magnification amplifier, also known as a powermate. A magnification amplifier works in a similar way to a Barlow lens, in that it magnifies the image. However, unlike a Barlow lens, a magnification amplifier is designed to be used with a specific eyepiece. And it can increase the magnification of your telescope by several times. Magnification amplifiers are a bit more expensive than Barlow lenses, but they can provide a significant increase in magnification and can be a good investment for those who want to get a closer look at celestial objects.

Powermate is a tele-extender, which means it increases the focal length of the telescope. This increased focal length results in higher magnification levels when used with an eyepiece. The Powermate achieves this by using a complex optical system that magnifies the image without introducing any distortion, reducing image brightness or decreasing contrast. One of the significant advantages of Powermate over other types of tele-extenders is that it maintains high image quality. Traditional Barlow lenses, which are also used to increase magnification, can produce a distorted image or reduce image clarity due to the introduction of additional glass elements. Powermate, on the other hand, maintains the optical quality of the telescope, delivering sharp, clear, and detailed images.


Another advantage of Powermate is that it is compatible with a wide range of eyepieces. This allows for increased flexibility when it comes to magnification options. The Powermate can be used with a range of eyepieces to produce different magnification levels, giving you more flexibility and versatility in your observing experience. Powermate also provides a more convenient way of changing magnification levels compared to swapping out eyepieces. Changing eyepieces can be time-consuming, requiring adjustments to the telescope’s focus and alignment. Powermate simplifies the process by allowing you to quickly and easily adjust the magnification level without having to make any additional adjustments to the telescope.

Additionally, Powermate can be used for astrophotography. It allows you to achieve high magnification levels while maintaining image quality, resulting in stunning and detailed images of the night sky. This makes it a valuable accessory for astrophotography enthusiasts looking to capture detailed images of celestial objects.

Advanced focuser

In addition to purchasing additional equipment, there are a few other modifications you can make to your commercial telescope to increase its magnification. One of these is to replace the standard focuser with a more advanced focuser that provides finer control over focus. This can be especially useful for high-magnification observations, as it will make it easier to achieve a sharp and clear image. Another modification that can increase the magnification of your commercial telescope is to add a field flattener, which will help to eliminate distortion and improve image quality.

It’s also important to remember that increasing the magnification of your commercial telescope will also increase the amount of light that is needed to produce a clear and sharp image. Therefore, you should make sure that your telescope is set up in a location with as little light pollution as possible, and that you are using the telescope under clear and dark skies. You may also want to consider purchasing a specialized filter to block out specific types of light that can interfere with your observations, such as light pollution or Moon light.

There are several ways to increase the magnification of your commercial telescope, including purchasing additional eyepieces, adding a Barlow lens or magnification amplifier, making modifications to the focuser and adding a field flattener. By making these modifications and additions to your setup, you can get a closer look at the stars and other celestial objects and deepen your appreciation for the beauty and complexity of the universe. So, go ahead and explore the night sky with your newly magnified telescope, and have fun!

FAQ Section for “How to Increase the Magnification of Your Telescope

Can I Increase Magnification Just by Changing Eyepieces?

Yes, using eyepieces with shorter focal lengths increases magnification.

What is a Barlow Lens and How Does it Affect Magnification?

A Barlow lens is an accessory that multiplies the telescope’s magnification, typically by 2x or 3x.

Is Higher Magnification Always Better?

Not necessarily. Higher magnification can decrease image brightness and sharpness, especially under poor atmospheric conditions.

How Does Telescope Aperture Affect Magnification?

A larger aperture allows for a clearer image at higher magnifications.

Can Atmospheric Conditions Impact Magnification?

Yes, atmospheric turbulence can blur images, limiting the effectiveness of high magnification.

Are Zoom Eyepieces a Good Option for Variable Magnification?

Zoom eyepieces offer flexibility, but they may have lower optical quality compared to fixed focal length eyepieces.

Will a Larger Telescope Always Provide Higher Magnification?

A larger telescope can provide higher magnification, but it also depends on the eyepiece and overall optical quality.

How Do I Choose the Right Eyepiece for Higher Magnification?

Choose an eyepiece with a shorter focal length and ensure it matches your telescope’s specifications.

Can I Use Multiple Barlow Lenses Together?

It’s technically possible, but it may not be practical as it can overly extend the telescope and degrade image quality.

What Should I Consider When Upgrading My Telescope for Higher Magnification?

Consider the telescope’s focal length, aperture size, and the quality of the mount and optics.