Reflector vs. Refractor Telescopes – Which Should You Get?

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So you’re looking to take up stargazing as your new hobby, yet you’re not certain what kind of a telescope would be better for you.

On the market the most popular types of telescopes are the reflector and the refractor, but what’s the difference?

To put it simply, the reflector telescopes use a combination of curved mirrors in order to form an image by reflecting the light. On the other hand, the refractor telescopes use special lenses in order to form an image, similar to that of the binoculars.

Reflecting telescope         

The use of a curved mirror or mirrors, depending on the design as it can use either a single or a combination of curved mirrors, gives this telescope the ability to reflect observed images back to our eyes.

Using this method to create an image makes the reflecting telescopes not have the vulnerability of having color aberration.

The way it works is by having a curved mirror position at the bottom of the telescope that reflects the light that comes from the opening at the other side, which then is reflected to a secondary mirror and then to the eyepiece where you can observe the image.

However, keep in mind that some reflecting telescopes do not come with a telescope diagonal, which means that for those telescopes the image will be upside down, if the telescope uses an even number of mirrors, or reversed to the side if it uses an odd number of mirrors.

Pros and Cons

The pros of the reflector are that they are better suited for deep-sky observing and have no chromatic aberration, aka ‘color fringing’. They are also highly cost-effective when compared to other similarly-sized refractors, as the reflecting telescopes are much cheaper to make thanks to the low cost of manufacturing for the mirrors they use.

This makes them a great entry-level telescope for beginners.

The short side of the reflecting telescopes is that it can be difficult to keep the optics in alignment if the user is not experienced enough.

Refracting telescope

The special lenses that the refractors use allow them to bend and focus the light, rather than simply reflecting it, in order to give an image.

Due to the special lenses they use, the refractors can suffer from chromatic aberration, giving an unwanted outline of color around the edges of an object.

If you’ve ever used binoculars, since they are basically two refracting telescopes mounted side-by-side, the chromatic aberration is something you’ve probably already experienced.

However, this issue is not present in “triplet” refractors which use three lenses instead of two in order to eliminate the chromatic aberration.

Pros and Cons

Because of their simple design, the refractors are much more user-friendly and reliable, needing little to no maintenance, thanks to the lenses being permanently aligned, aside from the occasional cleaning. They are great for observing the stars, the moon, and other planets, however, they do lack in the deep-space department.

Another great thing about the refracting telescope is that it doesn’t require a telescope diagonal, since the images are already shown right-side-up.

Their compact size makes them much more highly portable compared to their reflecting counterpart.

Yet, as previously mentioned all refracting telescopes suffer from chromatic aberration, due to the different wavelengths of light being bent by the lenses.

Also, the lenses are much more expensive than the mirrors used in the reflecting telescopes, therefore, the refractors are usually a bit more expensive when compared to similarly-sized reflecting telescopes.

Conclusion

To say that one telescope is better than the other would be a mistake, since both types have their advantages and their disadvantages.

If you’re looking for something more casual when it comes to stargazing or even just sightseeing, maybe you want to observe the moon or the stars, go birdwatching, etc., the refractor is a much better choice as even small planets are able to be seen with small telescopes.

Followed by the easy use and low maintenance, it comes to no surprise why it is the most used type of telescope.

The reflecting telescope, although a bit harder to use, navigate and maintain for complete newcomers, gives a much better experience when it comes to deep-sky observation and astrophotography. This is proven as the Newtonian Reflector is the go-to telescope when it comes to this hobby.

Related Questions

What kind of telescopes do astronomers use?

In the past astronomers used refractors when it came to their observations. Most modern observatories nowadays use reflectors when it comes to their deep sky observations, since these telescopes tend to be much bigger and better at the job. Additionally, large infrared telescopes and other exotic types are used today.

Which came first, the reflector or the refractor?

Although both telescopes were invented in the 17th century, the refracting telescope is considered to be the first of the two, as it was created somewhere around 1608 in the Netherlands. The reflecting telescope was invented by Sir Isaac Newton in 1668 in order to be the alternative to the refractor.

Why are there no new large refracting telescopes?

Since the lenses are much more expensive compared to the mirrors that reflecting telescopes use, the production of large refracting telescopes has been on the decline.

Can I use my reflecting telescope for solar?

NO! Do not use your reflecting telescope for solar projection as the telescope can easily overheat. A small refractor is ideal when it comes to solar observing, just try avoiding using anything larger than 90mm. Keep in mind that you must have an eyepiece and filters in order to do this. Some popular eyepieces are Plössls and Kellners.

Alternatively, if your sole intent is to do solar projecting try looking into catadioptric telescopes as they are specifically created just for solar observing, as they use a combination of reflection and refraction.

What size of a telescope do I need to observe galaxies?

Although it is possible to observe galaxies through a 4-inch telescope, the image will be filled with rough shapes. If you really want to observe galaxies you have to use a telescope with an aperture of 8 inches or more! 

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