150–200 mm Schmidt-Cassegrain on a GoTo alt-az
Celestron NexStar 6SE
Serious aperture in a tube half a metre long, on a computerised fork. The most capability per unit of storage space, at a price.
€1,549seen 7 Oct 2026 at Astroshop
- 152 mmAperture
- f/9.9Focal ratio
- 13.6 kgTypical weight
- 25–304×Useful magnification
Should you buy it?
- Yes if what you mainly want is the moon and the planets, nebulae, clusters and galaxies, by eye: that is what this family does best.
- No if your priority is taking it with me: other families do better for the same money.
Computed from its family's per-goal scores and its own numbers — not a rating, not one evening's opinion.
Where to buy
Also search at First Light Optics · Optique Unterlinden · Pierro Astro · Teleskop-Express (searches; neither price nor stock checked)
1 of these 5 links earn us a commission, marked above. Sorted by price, never by what pays. How this site is funded.
Prices are observed on the date shown, never live. Links marked paid link earn us a commission and cost you nothing extra.
What it shows, really
These circles are simulations, computed from the aperture, the magnification and the sky — indicative, not exact. A real night also depends on the turbulence, your eyes and your experience. Closer to the truth than the photo on the box; still not a promise.
Under a suburban sky (Bortle 6), through a common 25 mm eyepiece for wide targets and a 10 mm for planets. Every circle is the true field — nothing is enlarged.
Photo credits
These thumbnails are built from real photographs, scaled and darkened by the same arithmetic as the large view.
The numbers
Photo: Astroshop| Aperture | 152 mm |
|---|---|
| Focal ratio | 1500 mm · f/9.9 |
| Mount | Single-arm fork, GoTo alt-az |
| Typical weight | 13.6 kg |
| Eyepieces | 25 mm |
| Useful magnification | 25× to 304× at 152 mm |
| Resolution (Dawes) | 0.8″ — the tightest double star this aperture can split |
| Faintest star, suburban sky | around magnitude 12.2 |
| Observed price | €1,549 seen 7 Oct 2026 at Astroshop |
Made for
- The Moon and the planets
Aperture, focal length and tracking together — the combination high-power planetary work wants.
- Nebulae, clusters and galaxies, by eye
Real aperture, though the field is narrow and f/10 makes extended nebulae hard work.
- The Sun
In white light: sunspots with their penumbra, faculae near the edge, and granulation on a steady morning. Dawes' limit on the Sun: 0.8″ (116 ÷ 152 mm, arithmetic). It needs a certified cell over the front whose range holds its 181 mm outside diameter: the Omegon Helievo 172 (164–188 mm), €99 (seen 26 Sept 2026). Every time: certified filter over the front · finder capped · never an eyepiece filter · an adult with children · never without the filter · measure first.
Not made for
- Taking it with me
Compact for its aperture, but it is still a two-case operation.
The Sun, safely
No solar filter in the box
The Sun with this model
It needs a certified cell over the front whose range holds its 181 mm outside diameter: the Omegon Helievo 172 (164–188 mm), €99 (seen 26 Sept 2026).
In white light: sunspots with their penumbra, faculae near the edge, and granulation on a steady morning. Dawes' limit on the Sun: 0.8″ (116 ÷ 152 mm, arithmetic).
Past about 100 to 125 mm, daytime air rather than aperture generally sets the limit on the Sun (experience: the AAVSO solar observing guide).
The listing gives a fit of 164–188 mm across the outside of the tube. Clear aperture 172 mm. The listing names no standard; no international standard exists for filters on telescopes, binoculars or lenses (AAS).
Where to buy
1 of these 1 links earn us a commission, marked above. Sorted by price, never by what pays. How this site is funded.
Every time
- A certified solar filter over the FRONT of the instrument, fastened so it cannot slip or blow off.
- Cap or remove the finder. It is a second telescope, and it has no filter.
- Never a filter at the eyepiece end: the concentrated sunlight there can crack it in an instant.
- With children, an adult is there every time.
- Never look, or point, without the filter on. Check it before each use; a scratched or torn filter goes in the bin.
- Measure before ordering. A cell that sits loose can fall off.
Sources for the Sun
- American Astronomical Society — How to View a Solar Eclipse Safely — filters on optics go on the front; eclipse glasses never with optics; children supervised
- American Astronomical Society — Solar Filters for Optics — eyepiece filters are dangerous; the finder capped, removed or filtered; the filter attached securely
- American Astronomical Society — About the ISO 12312-2 Standard — EN ISO 12312-2:2015 covers naked-eye viewers only; no international standard covers filters on telescopes, binoculars or lenses
- Société astronomique de France — Guide des observations solaires — a filter at the front, never one screwed into the eyepiece, the finder capped
- NASA — Keep Your Eclipse Glasses to See the Sun's ‘Freckles’ — a large enough sunspot shows through eclipse glasses
- AAVSO — Le Guide d'Observation Solaire de l'AAVSO, v1.1 (2017), p. 6 — archived copy — “Les ouvertures plus grandes que 100 à 125 mm sont généralement limitées par les effets de turbulence atmosphérique”; 50 to 80 mm is enough to count sunspots
The family it belongs to: 150–200 mm Schmidt-Cassegrain on a GoTo alt-az
What it does well
- 200 mm of aperture in something one person can carry in two pieces
- GoTo plus tracking, which matters at high power and matters more when sharing a view
- Adapts to almost anything — imaging, planetary video, visual
What it costs you
- A 200 mm Dobsonian costs a third as much and shows the same amount
- Long cooling time and a narrow field
- Batteries, hand controllers and alignment stars, every single night
Worth knowing about this model
The 25 mm eyepiece in the box gives 60× on 152 mm, an exit pupil of 2.5 mm. At 1500 mm of focal length, through the 1.25-inch diagonal supplied, even the widest eyepiece shows about 1° of sky, so the largest nebulae and clusters do not fit. The corrector plate at the front dews over on damp nights. A car-lighter lead is in the box.
Everything about 150–200 mm Schmidt-Cassegrain on a GoTo alt-az →
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€1,549seen 7 Oct 2026 at Astroshop
Where to buy