Telescope Comparison
Celestron Omni XLT 150 vs Sky-Watcher Explorer 150PDS OTA
The Celestron Omni XLT 150 is a complete setup. The Sky-Watcher Explorer 150PDS OTA needs a mount before it's usable.
First light
Celestron · 150mm · £349
The sky-learner's equatorial scope
- 150mm newtonian reflector on a manual equatorial mount
- Good for: Moon, planets, bright star clusters and nebulae
- Setup includes rough polar alignment before observing — more steps than a simple alt-az
- Mount axes feel counterintuitive at first; users find they become natural after several sessions
- Keeps the door open for adding tracking motors and moving into astrophotography later
Sky-Watcher · 150mm · £229
The custom-rig optical tube
- 150mm newtonian reflector — optical tube only, no mount included
- 750mm focal length at f/5
- Requires a compatible mount before you can observe anything
- Best for: observers who already own a suitable mount or are building a specific imaging rig
- Not a complete purchase — budget at least £100–300 extra for a mount before observing
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
Same focal length — identical magnification with any given eyepiece. Differences come from optical design and coatings.
Focal ratio
Same focal ratio — the same eyepiece gives equivalent magnification and true field in both scopes.
Mount type
Sky-Watcher Explorer 150PDS OTA has no mount — add a compatible mount before you can observe. Celestron Omni XLT 150 is a complete ready-to-use system.
Weight (OTA)
Sky-Watcher Explorer 150PDS OTA's optical tube is 1.3kg lighter. Relevant if you plan to use it on multiple mounts or carry the tube to dark-sky sites separately.
Optical design
Both are Newtonian reflectors — the same optical formula. Any performance difference comes from collimation quality, focal ratio, and eyepiece choice, not the design itself.
At the eyepiece
Both scopes · same aperture
Both are 150mm Newtonian reflectors — light gathering is identical. What you see through each depends on your eyepieces, your sky, and the steadiness of the atmosphere, not which scope you bought. Saturn's rings separate clearly from the disk; in good seeing, the Cassini Division — the dark gap between the A and B rings — is a genuine target at moderate magnification. Jupiter shows two equatorial cloud bands reliably, four Galilean moons changing position night to night. The Orion Nebula (M42) shows real nebulosity around the Trapezium, which splits into four stars at moderate magnification. The Andromeda Galaxy (M31) fills a wide-field eyepiece, the bright core distinct from the outer halo. What separates these scopes is the mount, the setup experience, and where you can use them — not what you see through them.
The real tradeoff
Both scopes are capable. The question is which one fits the way you actually observe.
The Celestron Omni XLT 150 is a complete package — everything arrives in one box and you can observe the same day. The Sky-Watcher Explorer 150PDS OTA is a bare optical tube that needs a separate compatible mount before you can point it at anything, adding significant cost and complexity. Unless you already own a suitable mount, the Celestron Omni XLT 150 is the practical choice.
The dark side
Every scope has a personality. Here’s where each one gets difficult.
Celestron
Celestron Omni XLT 150
Mount axes feel counterintuitive at first
An equatorial mount does not move up/down and left/right as you expect — it follows the rotation of the sky. Users consistently report that it takes several sessions before it begins to feel natural.
Collimation: the skill nobody mentions in the listing
The mirrors go out of alignment with use. Stars look bloated rather than sharp when this happens. Users report that a Cheshire eyepiece makes collimation straightforward once learned, but most beginners don't discover they need it until their second or third month.
Sky-Watcher
Sky-Watcher Explorer 150PDS OTA
No mount included
You cannot observe until you buy a separate compatible mount — add at least £100–300 before you have a working telescope.
Nothing to look through on day one
Until a mount arrives, the optical tube is a piece of glass you cannot point at the sky.
Which is right for you?
Two different buyers. Two different right answers.
The sky-learner's equatorial scope
Celestron · Celestron Omni XLT 150
You’ll love this if…
- You want to understand how an equatorial mount works — and you're prepared to spend a few sessions on polar alignment before it becomes second nature
- You plan to observe from a fixed spot in the garden, where the mount can stay roughly polar-aligned between sessions
- Astrophotography is on your radar even if you're not starting there — this mount keeps that option open with a motor drive upgrade
This will frustrate you if…
- You find the equatorial mount's axes feel wrong — objects move in unexpected directions and polar alignment adds a step each session that takes several outings to become automatic
- You notice that stars look bloated rather than sharp and don't know why — users report this is usually a collimation issue that's straightforward to fix once you know about it, but the listing doesn't mention it
The custom-rig optical tube
Sky-Watcher · Sky-Watcher Explorer 150PDS OTA
You’ll love this if…
- You already own a compatible equatorial or alt-az mount — this is the optical tube you've specifically chosen to put on it
- You're building an imaging rig piece by piece and know exactly what you need at the end of a focuser
- Choosing an optical tube independently of the mount gives you more flexibility over your overall system
This will frustrate you if…
- You buy it without fully accounting for the mount — add at least £100–300 to the purchase price before you have a working telescope
- You expected a complete package and didn't realise this is a bare optical tube that cannot be used without a separate mount
Our verdict
This comparison has a catch: the Sky-Watcher Explorer 150PDS OTA is a bare optical tube. You cannot use it without a separate mount — which adds meaningful cost and complexity. The Celestron Omni XLT 150 is a complete, ready-to-observe package.
For most buyers, the Celestron Omni XLT 150 is the right choice — you can observe the same night it arrives. The Sky-Watcher Explorer 150PDS OTA makes sense if you already own a compatible mount, or are deliberately building a specific imaging setup piece by piece. If I had to choose for a first telescope: the Celestron Omni XLT 150, without hesitation.
Celestron Omni XLT 150
View Celestron Omni XLT 150 →Sky-Watcher Explorer 150PDS OTA
View Sky-Watcher Explorer 150PDS OTA →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 Omni XLT 150 | Sky-Watcher Explorer 150PDS OTA |
|---|---|---|
Aperture The most important spec — bigger = more light = better views | 150mm | 150mm |
Focal Length Longer = more magnification potential | 750mm | 750mm |
Focal Ratio Lower f-number = wider field of view; higher = more magnification per eyepiece | f/5 | f/5 |
Optical Design The type of optics — each design has different strengths | Newtonian Reflector | Newtonian Reflector |
Coatings Better coatings = more light transmission through the optics | XLT aluminium mirror coatings | Parabolic primary mirror with aluminium coating and SiO2 overcoat |
How do you point it?
| Spec | Celestron Omni XLT 150 | Sky-Watcher Explorer 150PDS OTA |
|---|---|---|
Mount Type The mechanical system that holds and moves the telescope | Equatorial | None (OTA only) |
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 Omni XLT 150 | Sky-Watcher Explorer 150PDS OTA |
|---|---|---|
Focuser Size 2" accepts wider eyepieces and gives better low-power views | 2" | 2" / 1.25" |
Focuser Type Rack-and-pinion is standard; Crayford and dual-speed are smoother | Crayford | Dual-speed Crayford (10:1) |
Size & weight
| Spec | Celestron Omni XLT 150 | Sky-Watcher Explorer 150PDS OTA |
|---|---|---|
OTA Weightⓘ Optical tube only — useful for comparing mount load capacity | 6.5kg | 5.2kg |
Total Weight Full setup including mount — this is what you lug to the car | 14kg | — |
Tube Length | 750mm | 710mm |
Tube Material | Steel | Aluminium |
What's in the box?
| Spec | Celestron Omni XLT 150 | Sky-Watcher Explorer 150PDS OTA |
|---|---|---|
Eyepieces Included eyepieces — more is better, but quality matters more than quantity | 25mm and 10mm Plössl | — |
Finder Scope Helps you locate areas of the sky before switching to the main eyepiece | StarPointer red dot | — |
Diagonal Tilts the eyepiece 90° for comfortable viewing — useful on refractors |
Blue highlight: Celestron Omni XLT 150 advantage · Amber highlight: Sky-Watcher Explorer 150PDS OTA advantage · Greyed cells: equal or subjective.