Telescope Comparison
Bresser Messier NT-203/800 OTA vs Omegon Advanced 150/750 EQ3
The Omegon Advanced 150/750 EQ3 is a complete setup. The Bresser Messier NT-203/800 OTA needs a mount before it's usable.
First light
Bresser · 203mm · £329
The custom-rig optical tube
- 203mm newtonian reflector — optical tube only, no mount included
- 800mm focal length at f/3.9
- 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
Omegon · 150mm · £279
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
The full picture
The numbers that separate these two scopes — and what they mean at the eyepiece.
Aperture
Bresser Messier NT-203/800 OTA 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
Bresser Messier NT-203/800 OTA's longer focal length reaches higher magnification with the same eyepiece — better reach for planetary detail. Omegon Advanced 150/750 EQ3's shorter focal length gives a wider true field — better for large open clusters and extended nebulae.
Focal ratio
Bresser Messier NT-203/800 OTA's faster f/3.9 delivers wider fields with any eyepiece — better for open clusters and large nebulae. Omegon Advanced 150/750 EQ3's f/5 provides more magnification per eyepiece — better for fine planetary detail.
Mount type
Bresser Messier NT-203/800 OTA has no mount — add a compatible mount before you can observe. Omegon Advanced 150/750 EQ3 is a complete ready-to-use system.
Weight (OTA)
Omegon Advanced 150/750 EQ3's optical tube is 1.4kg 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
Bresser
Bresser Messier NT-203/800 OTA
The Moon fills the field at low power with more detail than you'll have time to explore on any given night. Saturn's rings are unmistakable from the first session; in good seeing, the Cassini Division — the dark gap between the A and B rings — is a genuine target at higher magnification. Jupiter shows two equatorial cloud bands clearly, the four Galilean moons changing position night to night. The Orion Nebula (M42) shows wide nebulosity with the Trapezium splitting cleanly into four points at 80×. The Hercules Cluster (M13) begins to resolve into individual stars at the outer edges at higher magnification. The Andromeda Galaxy (M31) fills a wide-field eyepiece; the bright core and inner disc are obvious, and on a dark night the dust lane becomes visible with careful looking. The Bresser Messier NT-203/800 OTA gathers 1.8× more light than the Omegon Advanced 150/750 EQ3 — a difference that's marginal on bright targets but visible on fainter ones: dimmer galaxies, faint globular clusters, and extended nebulosity that sits below the threshold of the smaller aperture.
Omegon
Omegon Advanced 150/750 EQ3
The Moon fills the field at low power with more detail than you'll have time to explore on any given night. Saturn's rings are unmistakable from the first session; in good seeing, the Cassini Division — the dark gap between the A and B rings — is a genuine target at higher magnification. Jupiter shows two equatorial cloud bands clearly, the four Galilean moons changing position night to night. The Orion Nebula (M42) shows clear structure — nebulosity spreading around the Trapezium, which splits at moderate power. The Andromeda Galaxy (M31) shows a concentrated core clearly. The Hercules Cluster (M13) shows some resolution at the edges at higher magnification.
The real tradeoff
Both scopes are capable. The question is which one fits the way you actually observe.
The Omegon Advanced 150/750 EQ3 is a complete package — everything arrives in one box and you can observe the same day. The Bresser Messier NT-203/800 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 Omegon Advanced 150/750 EQ3 is the practical choice.
The dark side
Every scope has a personality. Here’s where each one gets difficult.
Bresser
Bresser Messier NT-203/800 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.
Omegon
Omegon Advanced 150/750 EQ3
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.
Which is right for you?
Two different buyers. Two different right answers.
The custom-rig optical tube
Bresser · Bresser Messier NT-203/800 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
The sky-learner's equatorial scope
Omegon · Omegon Advanced 150/750 EQ3
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
Our verdict
This comparison has a catch: the Bresser Messier NT-203/800 OTA is a bare optical tube. You cannot use it without a separate mount — which adds meaningful cost and complexity. The Omegon Advanced 150/750 EQ3 is a complete, ready-to-observe package.
For most buyers, the Omegon Advanced 150/750 EQ3 is the right choice — you can observe the same night it arrives. The Bresser Messier NT-203/800 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 Omegon Advanced 150/750 EQ3, without hesitation.
Bresser Messier NT-203/800 OTA
View Bresser Messier NT-203/800 OTA →Omegon Advanced 150/750 EQ3
View Omegon Advanced 150/750 EQ3 →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 | Bresser Messier NT-203/800 OTA | Omegon Advanced 150/750 EQ3 |
|---|---|---|
Apertureⓘ The most important spec — bigger = more light = better views | 203mm | 150mm |
Focal Length Longer = more magnification potential | 800mm | 750mm |
Focal Ratio Lower f-number = wider field of view; higher = more magnification per eyepiece | f/3.9 | 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 | Parabolic primary mirror with aluminium coating and SiO2 overcoat | Parabolic primary mirror with aluminium coating and SiO2 overcoat |
How do you point it?
| Spec | Bresser Messier NT-203/800 OTA | Omegon Advanced 150/750 EQ3 |
|---|---|---|
Mount Type The mechanical system that holds and moves the telescope | None (OTA only) | Equatorial |
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 | Bresser Messier NT-203/800 OTA | Omegon Advanced 150/750 EQ3 |
|---|---|---|
Focuser Size 2" accepts wider eyepieces and gives better low-power views | 2" | 2" |
Focuser Type Rack-and-pinion is standard; Crayford and dual-speed are smoother | Hexafoc dual-speed Crayford | Rack and pinion |
Size & weight
| Spec | Bresser Messier NT-203/800 OTA | Omegon Advanced 150/750 EQ3 |
|---|---|---|
OTA Weightⓘ Optical tube only — useful for comparing mount load capacity | 6.5kg | 5.1kg |
Total Weight Full setup including mount — this is what you lug to the car | — | 12.5kg |
Tube Length | 800mm | 710mm |
Tube Material | Carbon fibre composite | Aluminium |
What's in the box?
| Spec | Bresser Messier NT-203/800 OTA | Omegon Advanced 150/750 EQ3 |
|---|---|---|
Eyepieces Included eyepieces — more is better, but quality matters more than quantity | — | 10mm and 25mm eyepieces |
Finder Scope Helps you locate areas of the sky before switching to the main eyepiece | — | 6x30 finder scope |
Diagonal Tilts the eyepiece 90° for comfortable viewing — useful on refractors |
Blue highlight: Bresser Messier NT-203/800 OTA advantage · Amber highlight: Omegon Advanced 150/750 EQ3 advantage · Greyed cells: equal or subjective.