Orion SkyQuest XT12 Dobsonian — image 1
Orion

Orion SkyQuest XT12 Dobsonian

No longer sold

A 12-inch Dobsonian light bucket, the aperture serious visual observers dream about, delivering galaxy structure, faint nebulae and globular detail from one simple, affordable scope.

89/ 100
Polaris Score
#1 of 6 large Dobsonian
See the breakdown ↓
Aperture
305mm
Focal Length
1500mm
Focal Ratio
f/4.9
Mount Type
Dobsonian
Optical Design
Dobsonian
Weight
37.6 kg
Try in simulator →
No longer sold

Orion Telescopes (Telescope.com) ceased operations in 2024, so this model is no longer produced or carried by retailers we track. It still turns up regularly on the used market. We keep the page for reference — see current alternatives below.

See alternatives ↓
What it's built forOpen these in the simulator →

This telescope was built to gather light.

305 mm of aperture pulls in the faint light that galaxies and clusters live or die on. Point it up under a dark sky and objects that are rumors in smaller scopes resolve into real structure.

Sweet spot 230–380×Rewards dark skies
The view people remember

M13, breaking into a hundred stars.

A dark night takes the fuzzy ball and cracks its edges into individual suns — chains of them curving away from a core too dense to resolve.

See Hercules Cluster through this telescope →
01What it's good at

What it's best at — and the trade-offs.

305mm gathers over twice the light of an 8-inch, resolving spiral arms, dust lanes and faint nebulosity the eye can otherwise never reach
Best at
✓305mm gathers over twice the light of an 8-inch, resolving spiral arms, dust lanes and faint nebulosity the eye can otherwise never reach
✓The Dobsonian mount stays dead simple: point where you look, nudge to track, with nothing to power or align
✓At f/4.9 it delivers bright, wide low-power views that make sweeping the Milky Way a pleasure
✓It puts nearly every dollar into the mirror, which is why experienced observers keep chasing aperture like this
Trade-offs
!It is big and heavy: the tube alone is a real two-hands, plant-your-feet carry
!At f/4.9 stars show coma at the edge without a coma corrector
!It does not track, so objects drift and you re-center by hand at high power
!Collimation is expected and matters more at this fast focal ratio
02In plain English

What These Numbers Mean

305mm · f/4.9 · 1500mm FL · Dobsonian
Aperture
305 mm (12 inch)
Twelve inches gathers roughly 1,850 times the light of your eye and about 44 percent more than a 10 inch. Under dark skies that shows as spiral structure in the brighter galaxies, colour in planetary nebulae, and globular clusters resolved to the core.
Focal length
1500 mm
Long enough for 300x planetary work on steady nights, while a 30 mm eyepiece still gives 50x for sweeping. Large aperture plus long focal length is the classic deep-sky combination.
Focal ratio
f/4.9
Fast, which keeps the tube shorter than it would otherwise be and the fields wide, at the cost of demanding good eyepieces and careful collimation. A coma corrector genuinely improves the edge of the field here.
Optical design
Newtonian reflector
Maximum aperture per dollar with no false colour. The larger the mirror, the more collimation and cooling matter, so both become part of the routine at this size.
Weight
27 kg total
About 60 lb split between tube and base. Each piece is manageable alone, but this is a telescope you site in a garden rather than carry around, and the tube is bulky as well as heavy.
Cooldown
45 to 60 minutes
A twelve-inch mirror stores a lot of indoor heat, and the rising warm air blurs fine detail until it equalises. Put the scope out early and treat the first half hour as low-power sweeping.
03The Polaris Score

How it scores, and why.

89/100 · #1 of 6 large Dobsonian
89/ 100
Orion SkyQuest XT12 Dobsonian
#1 of 6 large Dobsonian
Performance
94
Ease of use
80
Portability
30
Upgrade potential
65

Polaris weighs optical capability, how easy the scope is to live with, how portable it is, and how far it takes you before you outgrow it — not list price or brand.

04Who it's for

An honest fit check.

Deep-sky observers hungry for the most aperture per dollar
Buy it if you
✓Deep-sky observers hungry for the most aperture per dollar
✓People with a car and storage space who chase faint galaxies and nebulae
✓Observers who prefer to learn the sky by star-hopping
Look elsewhere if you
!Anyone without the space or vehicle to move a very large tube and base
!Observers who need the scope to find objects automatically
!Deep-sky imagers, since the undriven base cannot track
05Build your rig

What to buy next — and where it leads.

9 pieces of gear, ordered by what changes the view most
Recommended upgrades
Pinpoint stars across the whole field★ Top pickApertura 1x Photographic Coma Corrector

Fixes edge coma inherent to this fast f/4.9 mirror

A worthwhile upgradeApertura Laser Collimator

Precise alignment the big fast optics reward

See wider, brighter deep-sky viewsGSO SuperView 30mm 2-inch

Bright wide-field views that play to the fast 12-inch tube

Observe better
Tame lunar glareGSO Moon Filter 13pct 1.25-inch

Improves contrast on nebulae and planets with this setup

Make nebulae popSVBony UHC 1.25-inch

Commonly paired with this telescope

Sharper planets & lunar detailCelestron X-Cel LX 7mm

Commonly paired with this telescope

A sharper everyday viewCelestron X-Cel LX 18mm

Commonly paired with this telescope

Show all compatible gear (6) →
Accessories
Double your magnificationTele Vue 2x Barlow 1.25-inch

Doubles magnification for closer planetary detail with this telescope

See wider, brighter deep-sky viewsExplore Scientific 68deg 28mm 2-inch

Commonly paired with this telescope

Lunar & planetary
Excellent
Deep-sky visual
Excellent
Astrophotography
Not its purpose, a visual scope
06The numbers

Full specifications.

6 measured and stated values
Optics
Optical DesignDobsonian
Aperture305mm
Focal Length1500mm
Focal Ratiof/4.9
Mount & drive
Mount TypeDobsonian
Physical
Weight37.6 kg
07Alternatives

For a different goal, start here.

3 alternatives, each mapped to the goal it wins at
Loaded package

Apertura AD12 Dobsonian

A 12-inch Dob bundled with a 2-inch Crayford, finder and extra eyepieces

→
Easier to transport

Sky-Watcher Flextube 250P Collapsible Dobsonian

A 10-inch that collapses shorter for the car if 12 inches is too much to move

→
Smaller sibling

Orion SkyQuest XT10

The 10-inch XT if you want most of the aperture in a more manageable tube

→
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