NexStar Evolution 6" Computerized Telescope vs NexStar Evolution 8" Computerized Telescope

Which one to buy

This is a genuine trade rather than an upgrade. The NexStar Evolution 8" Computerized Telescope gathers 1.8× the light, but at $11.81/mm it's dearer per millimetre than the NexStar Evolution 6" Computerized Telescope at $11.19/mm. Worth it if you're chasing faint objects, where aperture is the only thing that helps. Harder to justify if you mostly observe the Moon and planets, which are bright enough that the smaller scope shows them well.

What you'd notice at the eyepiece

With the 25mm eyepiece most telescopes ship with, the NexStar Evolution 6" Computerized Telescope gives 60× and the NexStar Evolution 8" Computerized Telescope 81×. The NexStar Evolution 8" Computerized Telescope's longer focal length magnifies harder on planets; the NexStar Evolution 6" Computerized Telescope shows a wider piece of sky, which is what you want for large nebulae and star clusters, and makes finding things easier. Try other eyepieces →

On the Moon and planets

Planets are bright, so this comes down to resolution and how much magnification the optics will carry before the image falls apart. The NexStar Evolution 8" Computerized Telescope resolves to 0.57″ and takes about 406×; the NexStar Evolution 6" Computerized Telescope resolves 0.77″ and tops out near 300×. On a night of steady seeing that's a visible difference on Jupiter's belts and the Cassini division. On an average night the atmosphere, not the telescope, sets the limit — which is why the gap matters less here than the aperture numbers suggest.

On deep-sky objects

Faint objects are where aperture is the only thing that helps. The NexStar Evolution 8" Computerized Telescope collects 1.8× the light and reaches about 0.7 magnitudes deeper — more galaxies within reach, and globular clusters that resolve into stars rather than staying a smudge.

Who each one suits

Both are catadioptric telescopes on the same GoTo mount, so the decision really is just aperture, price and whatever the brand adds around them. Both suit planetary and visual. The NexStar Evolution 6" Computerized Telescope is additionally set up for beginner.

Where you can actually buy them

Amazon does not currently sell the NexStar Evolution 6" Computerized Telescope — its listing is there but unavailable. OPT has it at $1679. This is normal for brands that sell mainly through astronomy dealers rather than Amazon, and it changes month to month — but it's worth knowing before you settle on one.

Which to choose

• You mostly observe the Moon and planets. The NexStar Evolution 8" Computerized Telescope — its 0.57″ resolution shows finer detail on a steady night.
• You're after faint galaxies and nebulae. The NexStar Evolution 8" Computerized Telescope, and it isn't close — 1.8× the light is the whole game on faint objects.
• Budget is the binding constraint. The NexStar Evolution 6" Computerized Telescope, $720 less — and it's also the better value per millimetre of aperture.

People also ask

What is the difference between NexStar 6 and 8?

Aperture and price. The NexStar Evolution 8" Computerized Telescope is 203mm against 150mm, so it gathers 1.8× the light, and it costs $720 more.

Questions Google reports people actually asking about this comparison. Answered from our own specs and live prices — anything the data can't settle isn't listed rather than guessed at.

What this page can't tell you

Everything above comes from aperture, focal length and price — measurable things. It says nothing about how steady the mount is under load, whether the focuser has play, how good the supplied eyepieces are, or what support is like a year in. Those routinely matter more than a few millimetres of aperture, and the only honest source is people who own one.

Worth reading before you buy: owner reports on Cloudy Nights — a twenty-year archive of people describing what these actually do at the eyepiece.