Telescope Comparison
Celestron NexStar Evolution 6 vs Celestron NexStar Evolution 8
The price gap is real. The question is whether the extra capability is worth it at your stage.
First light
Celestron · 150mm · £1,299
The automated deep-sky platform
- 150mm schmidt-cassegrain on a computerised mount with motorised tracking
- Good for: Moon, planets, bright nebulae, star clusters, and deep-sky objects
- GoTo system finds any object in its database after initial star alignment — no star atlas needed
- Tracking motors keep objects centred as Earth rotates — useful above 100×, essential for photography
- 12.5kg total — requires a fixed garden spot or car transport
Celestron · 203mm · £1,799
The automated deep-sky platform
- 203mm schmidt-cassegrain on a computerised mount with motorised tracking
- Good for: Moon, planets, bright nebulae, star clusters, and deep-sky objects
- GoTo system finds any object in its database after initial star alignment — no star atlas needed
- Tracking motors keep objects centred as Earth rotates — useful above 100×, essential for photography
- 17.5kg total — requires a fixed garden spot or car transport
The full picture
The numbers that separate these two scopes — and what they mean at the eyepiece.
Aperture
Celestron NexStar Evolution 8 gathers 1.8× more light. On bright targets — Moon, Saturn, Jupiter — you won't notice. On fainter targets — dim galaxies, faint globular clusters — the gap is real.
Focal length
Celestron NexStar Evolution 8's longer focal length reaches higher magnification with the same eyepiece — better reach for planetary detail. Celestron NexStar Evolution 6's shorter focal length gives a wider true field — better for large open clusters and extended nebulae.
Focal ratio
Same focal ratio — the same eyepiece gives equivalent magnification and true field in both scopes.
Mount type
Same mount type — setup experience and ergonomics will be similar. Differences lie in build quality and included accessories.
Weight (OTA)
Celestron NexStar Evolution 6's optical tube is 1.9kg lighter. Relevant if you plan to use it on multiple mounts or carry the tube to dark-sky sites separately.
Optical design
Both Schmidt-Cassegrain designs — versatile, compact, good for planets and deep-sky. Differences come from aperture and mount.
At the eyepiece
| Target | Celestron NexStar Evolution 6 | Celestron NexStar Evolution 8 |
|---|---|---|
| Planets | ||
| Moon | Excellent 150mm aperture at f/10 delivers superb high-magnification lunar detail — rilles, crater chains, and mountain shadows are crisp | Excellent 203mm aperture and f/10 focal ratio deliver razor-sharp high-magnification lunar detail — craterlets, rilles, and shadow play across the terminator |
| Saturn | Excellent 150mm aperture and 1500mm focal length resolve the Cassini Division and subtle cloud banding in good seeing | Excellent 203mm aperture and 2032mm focal length comfortably show ring structure, Cassini Division, and subtle cloud banding on the disc |
| Jupiter | Excellent Multiple cloud belts, GRS, and moon shadow transits visible at 150–250x | Excellent Multiple cloud belts, festoons, the Great Red Spot, and Galilean moon shadows are all within reach at 200×–300× in good seeing |
| Mars | Good 150mm aperture shows dark albedo features and polar cap at opposition; surface detail improves with a red filter | Excellent 203mm aperture and long focal length reveal polar cap, dark albedo features, and occasional dust storm activity at opposition |
Deep sky | ||
| Orion Nebula (M42) | Good Core and trapezium resolved well, but 1500mm focal length crops the full nebula extent | Good Bright core and Trapezium are vivid, but the 2032mm focal length crops the nebula's full extent — use with f/6.3 reducer for better framing |
| Andromeda Galaxy (M31) | Moderate 1500mm focal length shows only the bright core — the outer halo and companion galaxies overfill the field | Moderate Only the bright core is visible in the narrow field of view — the galaxy's full 3° extent is far beyond what any eyepiece can frame at this focal length |
| Open clusters | Moderate Narrow field crops large clusters like the Pleiades; compact clusters like M11 fare better | Moderate Many open clusters overfill the field — best for compact clusters like M11; the Pleiades and Double Cluster are impractical |
| Globular clusters | Good 150mm resolves outer stars in M13 and M92; cores remain granular but impressive | Excellent A highlight of this scope — 203mm resolves individual stars in M13, M92, and M5; the long focal length provides detailed high-power views |
| Faint galaxies | Good 150mm gathers enough light for M51, M81/M82, and other Messier galaxies as soft glows with some structure hints | Good 203mm gathers enough light to detect galaxies in the Virgo cluster and Leo Triplet as soft glows with hints of structure in the brightest |
| Milky Way / wide field | Not recommended 1500mm focal length is far too narrow for sweeping star fields — field of view under 1° | Not recommended At 2032mm focal length the true field is far too narrow for sweeping star fields — this is fundamentally the wrong tool for wide-field observing |
Other | ||
| Double stars | Excellent 150mm aperture at f/10 cleanly splits sub-arcsecond pairs; diffraction-limited performance rewards tight doubles | Excellent 203mm aperture resolves to ~0.57 arcseconds; the f/10 focal ratio provides clean, high-contrast Airy patterns ideal for splitting close pairs |
| Astrophotography (planetary) | Good 150mm at 1500mm focal length with GoTo tracking is well suited to lucky imaging with a planetary camera | Good 203mm aperture and 2032mm native focal length on a tracking mount produce excellent planetary video frames; Barlow can push to f/20 for ideal sampling |
| Astrophotography (deep sky) | Moderate Alt-az GoTo mount limits exposures to ~15–30 seconds before field rotation becomes apparent; bright targets only | Moderate Alt-az GoTo mount tracks but introduces field rotation limiting exposures to a few seconds; suitable for EAA with stacking, not for traditional long-exposure imaging |
The real tradeoff
Both scopes are capable. The question is which one fits the way you actually observe.
Celestron NexStar Evolution 6
- You'll get 90% of the same experience as the 8-inch — same WiFi app control, same battery-powered convenience, same alt-az GoTo mount — but you'll save £500 and shave about a kilogram off the carry weight, which matters more than you'd think when you're hauling gear through the house at 11pm.
- Your views of Saturn's rings and Jupiter's cloud belts will be genuinely impressive, and at 1500mm focal length you'll still have a slightly wider true field of view than the 8-inch — roughly 0.8° versus 0.35° with a 25mm Plössl — so large open clusters and extended nebulae are a little less claustrophobic to frame.
- You'll hit a ceiling on faint deep-sky targets sooner than the 8-inch: galaxies in the Virgo cluster will be there, but they'll be dim, featureless smudges where the extra 53mm of aperture would have started pulling out hints of structure and resolved individual stars at the edges of globulars like M13.
Celestron NexStar Evolution 8
- You'll notice the aperture jump the moment you point at a globular cluster — M13 goes from 'bright fuzzy ball' to a granular, sparkling field of individually resolved stars, and that upgrade carries across to every deep-sky target you visit.
- You'll pay for that aperture in a noticeably narrower field of view: at 2032mm focal length, the Orion Nebula loses its wings, M31 shrinks to just a bright core, and you'll find yourself constantly thinking about which eyepiece can claw back some field — the included 40mm Plössl won't cut it, so budget for a 2-inch wide-field eyepiece on day one.
- You'll spend the same setup time as the 6-inch — same WiFi alignment process, same battery convenience, same single-arm fork — but the slightly heavier 14kg assembled weight and longer tube mean it's just on the edge of what feels like a one-trip carry from the car.
The dark side
Every scope has a personality. Here’s where each one gets difficult.
Celestron
Celestron NexStar Evolution 6
The alt-az GoTo mount introduces field rotation, capping useful deep-sky imaging exposures at roughly 15–30 seconds — enough for planetary capture and basic EAA, but a hard wall for anyone expecting to do traditional long-exposure astrophotography.
The closed-tube SCT design needs 30–45 minutes to reach thermal equilibrium; until then, planetary views will shimmer and refuse to snap into focus — so a spontaneous 20-minute session rarely delivers the scope's best performance.
At 1500mm focal length the true field of view is so narrow (~0.8° with a 25mm Plössl) that the GoTo system isn't a luxury — it's a necessity; star-hopping manually through a keyhole is an exercise in frustration.
Celestron
Celestron NexStar Evolution 8
The SCT corrector plate is a dew magnet in UK conditions — without a dew shield or heated strip, you can lose your session in under an hour on a damp night, making a £30–£60 dew accessory effectively mandatory.
The included 40mm Plössl eyepiece has poor eye relief and doesn't do the optics justice; most owners replace it immediately, so factor in at least another £80–£150 for a decent wide-field eyepiece before you've even had a proper first light.
Collimation can drift during transport, and the star-test adjustment process involves tweaking the secondary mirror via three small screws while looking through the eyepiece — a procedure that's straightforward once you've learned it but genuinely intimidating the first few times.
Which is right for you?
Two different buyers. Two different right answers.
The automated deep-sky platform
Celestron · Celestron NexStar Evolution 6
You want a modern, self-contained GoTo scope for detailed planetary and lunar viewing from your suburban garden, and you'd rather keep £500 in your pocket for eyepieces and filters than chase the last increment of deep-sky performance. You're an intermediate observer who values the WiFi convenience and built-in battery but doesn't need to resolve individual stars in every globular cluster. If your priority list reads planets first, compact deep-sky second, and wide-field sweeping not at all, the 6-inch gives you a genuinely capable scope at a more palatable price — just don't expect it to double as an astrophotography platform.
The automated deep-sky platform
Celestron · Celestron NexStar Evolution 8
You've already decided you want an 8-inch aperture and the question is whether the Evolution platform justifies the £1799 price tag — and if your main use is high-magnification visual observing with GoTo convenience and no external power cables, it does. You'll love this if you're chasing resolved globular clusters, planetary detail at 250×, and EAA sessions stacking short exposures through a camera. This isn't for you if you're budget-conscious after the initial purchase — the scope practically demands a dew heater, a better eyepiece, and possibly a 2-inch diagonal before it's truly complete, pushing total investment well past £2000.
Our verdict
These two are closer than most comparisons on this site. The spec differences are genuine — mount type, focal ratio — but neither is the wrong answer for a typical observer starting out.
If I had to choose between them: the Celestron NexStar Evolution 6 is the scope most people will be using regularly six months from now. The Celestron NexStar Evolution 8 rewards you more once you know what you're doing — it's worth revisiting after your first year.
Celestron NexStar Evolution 6
View Celestron NexStar Evolution 6 →Celestron NexStar Evolution 8
View Celestron NexStar Evolution 8 →Deep field: Full specifications
Every data point, for those who want to go further.
Full specifications
Fields highlighted in blue or amber indicate the better value for that spec. Data is manufacturer-stated and may vary.
How much can it see?
| Spec | Celestron NexStar Evolution 6 | Celestron NexStar Evolution 8 |
|---|---|---|
Apertureⓘ The most important spec — bigger = more light = better views | 150mm | 203mm |
Focal Length Longer = more magnification potential | 1500mm | 2032mm |
Focal Ratio Lower f-number = wider field of view; higher = more magnification per eyepiece | f/10 | f/10.01 |
Optical Design The type of optics — each design has different strengths | Schmidt-Cassegrain | Schmidt-Cassegrain |
Coatings Better coatings = more light transmission through the optics | StarBright XLT fully multi-coated on all optical surfaces | StarBright XLT fully multi-coated on all optical surfaces |
How do you point it?
| Spec | Celestron NexStar Evolution 6 | Celestron NexStar Evolution 8 |
|---|---|---|
Mount Type The mechanical system that holds and moves the telescope | GoTo (Computerised) | GoTo (Computerised) |
GoTo Computer-controlled pointing — finds any of thousands of objects automatically | ||
Tracking Motor keeps objects centred as the Earth rotates — essential for astrophotography |
The focuser
| Spec | Celestron NexStar Evolution 6 | Celestron NexStar Evolution 8 |
|---|---|---|
Focuser Size 2" accepts wider eyepieces and gives better low-power views | 1.25" | 1.25" |
Focuser Type Rack-and-pinion is standard; Crayford and dual-speed are smoother | SCT rear-cell focuser | SCT rear-cell focuser |
Size & weight
| Spec | Celestron NexStar Evolution 6 | Celestron NexStar Evolution 8 |
|---|---|---|
OTA Weightⓘ Optical tube only — useful for comparing mount load capacity | 3.5kg | 5.4kg |
Total Weightⓘ Full setup including mount — this is what you lug to the car | 12.5kg | 17.5kg |
Tube Length | 394mm | 432mm |
Tube Material | Aluminium | Aluminium |
What's in the box?
| Spec | Celestron NexStar Evolution 6 | Celestron NexStar Evolution 8 |
|---|---|---|
Eyepieces Included eyepieces — more is better, but quality matters more than quantity | 25mm Plössl | 25mm Plössl |
Finder Scope Helps you locate areas of the sky before switching to the main eyepiece | StarPointer red dot finder | StarPointer red dot finder |
Diagonal Tilts the eyepiece 90° for comfortable viewing — useful on refractors |
Smart features
| Spec | Celestron NexStar Evolution 6 | Celestron NexStar Evolution 8 |
|---|---|---|
Built-in Camera Records and stacks images automatically — no separate camera needed | ||
App Controlled | ||
WiFi | ||
Battery Included |
Blue highlight: Celestron NexStar Evolution 6 advantage · Amber highlight: Celestron NexStar Evolution 8 advantage · Greyed cells: equal or subjective.