It can be hard to assess how good a telescope really is just from reading the specifications sheet. Just seeing some numbers in a table doesn’t really tell you much about whether or not a telescope will match your expectations.

A person’s first telescope can make or break their stargazing experience for life. If they go with a low-quality product or have higher expectations about what they are going to see through it, they can end up disappointed and might never give it another try. This is why it is so important that you know what to expect from your telescope and understand what you are going see with it.

In this article, we are going to focus on 70mm telescopes as they are quite common and they are one of the most typical ranges.

What does “70mm” mean?

Whenever you see a number with a unit behind a telescope name it usually refers to the telescope’s aperture. The aperture in a telescope is the size of the frontal lens or mirror, the one that captures the light.

In the case of 70mm telescopes, the “mm” stands for millimeters and is equivalent to 2.7 inches.

Who are these telescopes good for?

70mm telescopes are entry-level products. They are made for kids and teenagers who are curious about astronomy and are looking to get their first telescope.

Scopes in this range will usually not break the bank. They are some of the cheapest you will find. That doesn’t necessarily mean they are bad, simply that they are made for a specific audience who is just getting started with stargazing.

As a general rule, I’d personally recommend them only for kids under the age of 15 or if you really really want a telescope now but you are on a super tight budget. Otherwise, you might want to make the jump to the 100mm range or higher.

The exception to the rule is if you are looking specifically for a travel/camping telescope. 70mms are usually light and easy to carry around, making them a valid option if you are planning to bring your telescope on trips.

Pros and Cons

Pros

  • Generally light and small, easy to carry around.
  • Great pricing
  • Plenty of options. All the good manufacturers make at least one product in this range.

Cons

  • The small lenses lead to a low-resolution image.
  • Few options when it comes to magnification. One of the biggest drawbacks of small aperture lenses is they don’t allow you to use high magnification eyepieces. It doesn’t matter if you try to use 300x magnification. It’s going to look the same as 100x magnification because your telescope is gathering a limited amount of light. The highest useful magnification per inch of aperture is 50x, meaning a 70mm aperture can only go as high as 135x magnification.
  • They can be outgrown really fast. Someone who enjoys looking at the stars will want to move up really fast.

What can you expect to see with them?

There is no exact data as to exactly how far and how good you can see certain objects with a telescope depending on its aperture because there are other important variables like focal length, magnification, the quality of the lenses/mirrors, and even the weather so consider this section a bit anecdotical.

With a 70mm telescope, you will easily be able to see every planet in the Solar System. You will also be able to take a great look at the Moon and clearly distinguish most of its recognizable features and craters.

Mars will look great. With some luck, depending on the viewing conditions and how close it is to Earth, you might be able to distinguish its poles and maybe some of the bigger areas.

The outside planets beyond the asteroid belt will be seen mostly in one single color and it is unlikely you will be able to capture any of their shades. For example, Jupiter will most likely look like a light yellow spot and Neptune a sky blue dot. Saturn’s rings might be recognizable under certain conditions, but they will look the same color as the planet.

Pluto and the other dwarf planets in the Solar System will most likely be out of reach.

As for stars, some calculations can be made to approximately determine the maximum limit a telescope can reach. A star’s brightness is measured in magnitude. The higher the magnitude, the dimmer the object. The magnitude limit of a 70mm telescope is about 11.9. For reference, the brightest stars in the sky that can be seen with the naked eye like Polaris, Vega, and Antares have a magnitude below 3. Proxima Centauri, a small star with a magnitude of 11 would be an example of a star that can be seen with a 70mm telescope but not with the naked eye.

You should be able to see some of the beautiful mixes of colors in nebulas, specially the most prominent ones like Orion’s Nebula. They will look a lot better in long exposure photos though.

Photos taken with 70mm telescopes

Here are some photos that you might find useful to understand what you can expect to see through the lens.

Please note some of these photos might have been taken with long exposure times, meaning they might look with a bit more colors what you would see in real life. Also, not all were taken with exactly 70mm telescopes, some were taken with 68 to 75 lenses, but they should be similar enough.

What are the best telescopes in this range?

Here are our two recommendations of what we believe are the highest quality products in this category. There are not many good Newtonian telescopes in this range so both of them are refractors. If you don’t know what any of that means, don’t worry, you don’t need to understand the differences until you go to a higher aperture.

SOLOMARK’s 70EQ Refractor

This is probably the best telescope in the 70mm lens range. It has very good optics for its size, a decent, sturdy tripod and comes with two standard Plössl eyepieces, a 10mm, and a 20mm, these should give you a magnification of 70x and 35x respectively.

This is probably the best telescope in the 70mm lens range. It has very good optics for its size, a decent, sturdy tripod and comes with two standard Plössl eyepieces, a 10mm, and a 20mm, these should give you a magnification of 70x and 35x respectively.

Tip: You will generally want to use the 10mm for planets and the 20mm for star clusters.

One great thing about this SOLOMARK is it already comes with a smartphone camera adapter so you can immediately start taking pictures and video with it.

Check it out on Amazon

Orion GoScope III

Orion is one of the most recognizable and reputable brands in the telescope manufacturing industry. This is the newest version of their GoScope entry-level series.

While the GoScope doesn’t shine for showing the best images, its benefits come in its ultra-compact design, lightness, and portability.

This is the entry-level telescope we would recommend to someone with a small kid or teenager that doesn’t have much space to have it set up all the time or that plans to bring it outdoors constantly.

It comes with its own handy backpack that has separate compartments for every piece so you don’t run the risk of scratching anything.

I only wish it would come with a smartphone camera adapter included, but you can get that separately.

Due to its size and the max height of the tripod, I wouldn’t get this for an adult, but it should work great for a kid.

Check it out on Amazon

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