Telescope Comparison
Celestron NexStar 6SE vs Sky-Watcher SkyMax 150 Pro + HEQ5
The specs are close. The experience isn't.
First light
Celestron · 150mm · £999
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
- 11.5kg total — requires a fixed garden spot or car transport
Sky-Watcher · 150mm · £999
The automated deep-sky platform
- 150mm maksutov-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
- 24kg 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
Equal light-gathering. Aperture won't settle this comparison — the mount, focal ratio, and observing experience are what differ.
Focal length
Sky-Watcher SkyMax 150 Pro + HEQ5's longer focal length reaches higher magnification with the same eyepiece — better reach for planetary detail. Celestron NexStar 6SE's shorter focal length gives a wider true field — better for large open clusters and extended nebulae.
Focal ratio
Celestron NexStar 6SE's faster f/10 delivers wider fields with any eyepiece — better for open clusters and large nebulae. Sky-Watcher SkyMax 150 Pro + HEQ5's f/12 provides more magnification per eyepiece — better for fine planetary detail.
Mount type
Same mount type — setup experience and ergonomics will be similar. Differences lie in build quality and included accessories.
Weight (OTA)
Similar optical tube weight. Any portability difference between these setups comes from the mount, not the tube itself.
Optical design
Celestron NexStar 6SE is a Schmidt-Cassegrain (mirror and corrector, versatile focal lengths); Sky-Watcher SkyMax 150 Pro + HEQ5 is a Maksutov-Cassegrain (mirror and lens corrector, compact tube). Different optical formulas produce different strengths — reflectors give more aperture per pound; refractors give sharper contrast and require no collimation.
At the eyepiece
| Target | Celestron NexStar 6SE | Sky-Watcher SkyMax 150 Pro + HEQ5 |
|---|---|---|
| Planets | ||
| Moon | Excellent 150mm aperture and f/10 focal ratio reward high magnification — craterlets, rilles, and sharp terminator shadows are all accessible | Excellent 150mm aperture and f/12 focal ratio deliver exceptional lunar detail — rilles, crater terraces, and shadow play at high magnification |
| Saturn | Excellent 150mm and 1500mm focal length put Cassini Division, ring shadow, and disc banding within reach in steady seeing | Excellent 150mm aperture and 1800mm focal length clearly show the Cassini Division, disc banding, and shadow of the rings on the globe |
| Jupiter | Excellent Multiple cloud belts, Great Red Spot, and moon shadow transits visible; 1500mm focal length gives a generously sized disc | Excellent Multiple cloud belts, the Great Red Spot, and moon shadow transits are visible; 1800mm focal length gives large image scale |
| Mars | Good Polar cap and major dark albedo features visible at opposition; 150mm is below the 200mm threshold for truly detailed Mars observation | Good 150mm aperture shows polar cap and major dark surface features at opposition; falls short of the 200mm+ needed for Excellent |
Deep sky | ||
| Orion Nebula (M42) | Good Bright nebulosity and Trapezium are impressive, but the 1500mm focal length crops the full extent of the nebula; f/10 doesn't favour wide-field context | Good Bright core, trapezium stars, and inner nebulosity are well-resolved, but 1800mm focal length frames only the central region |
| Andromeda Galaxy (M31) | Moderate 1500mm focal length frames only the bright core — the outer halo and full disc extend well beyond the field even with a wide eyepiece | Moderate 1800mm focal length crops heavily — only the bright nucleus and inner core are visible; outer spiral arms are entirely out of field |
| Open clusters | Moderate Larger clusters like the Pleiades and Double Cluster overfill the field; works better on compact clusters like M35 or M11 | Moderate Narrow field restricts most large open clusters; compact clusters like M11 are rewarding but Pleiades or Double Cluster overflow the field |
| Globular clusters | Good M13 and M5 show granular texture with partial star resolution at the edges; 150mm is below the threshold for full resolution across the cluster | Good 150mm resolves stars at the edges of M13 and M92; the long focal length helps by providing high magnification natively |
| Faint galaxies | Good 150mm gathers enough light to show structure in brighter galaxies like M51 and M104; fainter targets appear as dim smudges | Good 150mm gathers enough light for brighter Messier and some NGC galaxies, though the narrow field makes finding them harder |
| Milky Way / wide field | Not recommended 1500mm focal length gives far too narrow a field for sweeping Milky Way views — this scope is the opposite of a wide-field instrument | Not recommended 1800mm focal length produces far too narrow a field for star-field sweeping — less than 1° even with the longest eyepieces |
Other | ||
| Double stars | Excellent 150mm aperture and f/10 focal ratio produce clean Airy discs — excellent for splitting close pairs and showing colour contrast | Excellent 150mm aperture with f/12 unobstructed optics produces clean, high-contrast Airy discs ideal for splitting tight pairs down to ~0.8 arcseconds |
| Astrophotography (deep sky) | Moderate Alt-az GoTo mount causes field rotation limiting exposures to a few seconds; usable for EAA and short-exposure stacking but not long-exposure imaging | Moderate HEQ5 provides equatorial tracking but f/12 demands impractically long exposures for faint targets; narrow field limits suitable subjects |
| Astrophotography (planetary) | Good 1500mm focal length and tracking mount suit lucky-imaging with a planetary camera; 150mm aperture gives solid detail but falls short of 200mm+ scopes | Good 150mm aperture and 1800mm native focal length give large image scale for lucky imaging; HEQ5 tracking keeps targets centred |
The real tradeoff
Both scopes are capable. The question is which one fits the way you actually observe.
Celestron NexStar 6SE
- You'll be observing within ten minutes of stepping outside — the alt-az GoTo alignment is quick, the whole rig fits on a patio table, and you can carry it out in one trip, which means you'll actually use it on weeknight impulse sessions.
- You'll get genuinely satisfying planetary views — Jupiter's belts, Saturn's Cassini Division, lunar rilles — but you'll also be able to swing over to M13 or the Ring Nebula and enjoy compact deep-sky targets without feeling like you bought a one-trick scope.
- You'll notice the single-arm fork wobble every time you refocus at high power — those 2–3 seconds of vibration feel longer than they sound, and you'll learn to wait with your hands off the scope before judging a planetary view.
Sky-Watcher SkyMax 150 Pro + HEQ5
- You'll spend your first fifteen minutes on polar alignment and balancing a 24kg rig before you see anything — this is a scope you set up deliberately, not one you grab on a whim, and that upfront investment shapes every session.
- You'll be rewarded with razor-sharp planetary detail at f/12 and an equatorial mount that tracks without field rotation, which means you can push magnification higher and longer than the 6SE allows, and you have a genuine pathway into planetary imaging with a high-speed camera.
- You'll find deep-sky observing frustrating — the 1800mm focal length crops everything aggressively, and you'll keep running into targets that simply don't fit the field, so your sessions will naturally gravitate toward the Moon, planets, and doubles where this scope excels.
The dark side
Every scope has a personality. Here’s where each one gets difficult.
Celestron
Celestron NexStar 6SE
The single-arm fork mount transmits every touch as a 2–3 second vibration — at 200x+ on planets, you'll refocus, then wait, then look, every single time.
No 2-inch visual back is included, so your maximum true field of view is stuck at roughly 0.8° with the stock eyepiece until you buy the adapter separately.
The alt-az GoTo mount causes field rotation during any sustained exposure, hard-limiting astrophotography to a few seconds per frame at most — planetary snapshots are possible, but deep-sky stacking is not.
Sky-Watcher
Sky-Watcher SkyMax 150 Pro + HEQ5
The sealed Maksutov tube takes 30–60 minutes to reach thermal equilibrium — if you don't plan for cool-down, your first half-hour of planetary viewing will be soft and shimmery from tube currents.
At around 24kg combined, the HEQ5 is near its practical payload limit with this OTA and accessories — adding a camera, guidescope, and dew heater pushes you into territory where tracking accuracy suffers.
The corrector plate dews up readily in humid conditions, and without a dew heater you'll lose your view mid-session — budget for one as a near-mandatory accessory on top of the purchase price.
Which is right for you?
Two different buyers. Two different right answers.
The automated deep-sky platform
Celestron · Celestron NexStar 6SE
You want a scope you'll actually use on a clear Tuesday night. You care about planets and the Moon but you also want to tour bright Messier objects without feeling locked out of deep-sky entirely. You value portability and quick setup over ultimate tracking precision, and you're not planning to image anything beyond a phone snap through the eyepiece. If your priority is maximum time at the eyepiece with minimum fuss, the 6SE fits your life better than a heavier equatorial rig ever will.
The automated deep-sky platform
Sky-Watcher · Sky-Watcher SkyMax 150 Pro + HEQ5
You already know you're a planetary observer and you want the sharpest views your budget allows, with a clear upgrade path into lucky-imaging with a high-speed camera. You don't mind spending fifteen minutes on polar alignment because you plan to stay out for a long session, and you want equatorial tracking that won't rotate the field. You have space for a 24kg setup and you're not expecting to sweep wide-field deep-sky targets — you want to push magnification on Jupiter, split tight doubles, and eventually capture high-resolution planetary frames.
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 6SE is the scope most people will be using regularly six months from now. The Sky-Watcher SkyMax 150 Pro + HEQ5 rewards you more once you know what you're doing — it's worth revisiting after your first year.
Celestron NexStar 6SE
View Celestron NexStar 6SE →Sky-Watcher SkyMax 150 Pro + HEQ5
View Sky-Watcher SkyMax 150 Pro + HEQ5 →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 6SE | Sky-Watcher SkyMax 150 Pro + HEQ5 |
|---|---|---|
Aperture The most important spec — bigger = more light = better views | 150mm | 150mm |
Focal Length Longer = more magnification potential | 1500mm | 1800mm |
Focal Ratio Lower f-number = wider field of view; higher = more magnification per eyepiece | f/10 | f/12 |
Optical Design The type of optics — each design has different strengths | Schmidt-Cassegrain | Maksutov-Cassegrain |
Coatings Better coatings = more light transmission through the optics | StarBright XLT fully multi-coated on all optical surfaces | Fully multi-coated Maksutov-Cassegrain optics |
How do you point it?
| Spec | Celestron NexStar 6SE | Sky-Watcher SkyMax 150 Pro + HEQ5 |
|---|---|---|
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 6SE | Sky-Watcher SkyMax 150 Pro + HEQ5 |
|---|---|---|
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 | Rear-cell focuser |
Size & weight
| Spec | Celestron NexStar 6SE | Sky-Watcher SkyMax 150 Pro + HEQ5 |
|---|---|---|
OTA Weightⓘ Optical tube only — useful for comparing mount load capacity | 3.5kg | 4.2kg |
Total Weightⓘ Full setup including mount — this is what you lug to the car | 11.5kg | 24kg |
Tube Length | 394mm | 480mm |
Tube Material | Aluminium | Aluminium |
What's in the box?
| Spec | Celestron NexStar 6SE | Sky-Watcher SkyMax 150 Pro + HEQ5 |
|---|---|---|
Eyepieces Included eyepieces — more is better, but quality matters more than quantity | 25mm Plössl | 25mm Super eyepiece |
Finder Scope Helps you locate areas of the sky before switching to the main eyepiece | StarPointer red dot finder | 8x50 right-angle finder with illuminated reticle |
Diagonal Tilts the eyepiece 90° for comfortable viewing — useful on refractors |
Blue highlight: Celestron NexStar 6SE advantage · Amber highlight: Sky-Watcher SkyMax 150 Pro + HEQ5 advantage · Greyed cells: equal or subjective.