ZWO AM3N Harmonic Equatorial Mount — image 1
ZWO

ZWO AM3N Harmonic Equatorial Mount

The AM5N's smaller sibling and the lightest serious imaging mount ZWO makes, a harmonic (strain-wave) mount whose gears hold an 8 kg rig with no counterweight, in a 3.6 kg head that disappears into a daypack. The harmonic mount for imagers who count every gram.

89/ 100
Polaris Score
Performance · ease · portability · upgrade path
See the breakdown ↓
GoTo
Yes
Head Weight
3.6 kg
Imaging Payload
8 kg
Mount Type
Harmonic (strain wave)
Payload Capacity
8 kg
Tracking
Yes
From$1,499

Lowest in 90 daysLowest ever tracked

Price tracked by PolarisObserved 97 timesTracking since Jul 2026

Where to buy

Verified 13h ago · prices tracked daily

01What it's good at

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

Carries a real ~8 kg imaging rig with no counterweight, the harmonic gearing is strong enough that there's no heavy balance bar to pack or fuss with
Best at
✓Carries a real ~8 kg imaging rig with no counterweight, the harmonic gearing is strong enough that there's no heavy balance bar to pack or fuss with
✓3.6 kg head, the most packable mount ZWO makes, built for travelling to dark skies
✓Same modern imaging stack as the AM5N: GoTo, plate-solving with a ZWO ASIAIR, and autoguiding, it just carries a lighter load
Trade-offs
!8 kg no-counterweight ceiling, less headroom than the AM5N, so it favours small refractors over heavy scopes
!Slightly more 'periodic error' (a tiny repeating tracking wobble from the gears) than premium worm-gear mounts, autoguiding cancels it in practice
!Usually sold with ZWO's carbon tripod; bare-head availability varies by region
02In plain English

The numbers, in plain English.

8kg payload
Payload
8 kg, no counterweight
Eight kilograms is enough for a 70 to 100 mm apochromat with camera, filter wheel and guiding, which is where most deep-sky imaging actually happens. It is not enough for a large SCT or a heavy astrograph.
Head weight
3.6 kg
Under 8 lb. With a carbon tripod the entire mount and support fits in a backpack, which makes travelling to dark skies a decision rather than an expedition.
Drive type
Harmonic (strain wave)
The gearing holds an unbalanced load, so no counterweight is needed and setup is fast. The cost is periodic error that needs autoguiding to control, which at these focal lengths is easily managed.
Mount class
Equatorial with integrated ASIAIR support
It tracks equatorially so exposures can be long, and it is designed to be driven by an ASIAIR, which removes the laptop from a portable setup entirely.
Tripod requirement
Rigid tripod essential
Without a counterweight to balance the load, tripod stiffness becomes the limiting factor in guiding performance. A light photo tripod will undo the mount's advantages.
03The Polaris Score

How it scores, and why.

89/100
89/ 100
ZWO AM3N Harmonic Equatorial Mount

Scores high for doing nearly everything the AM5N does in a lighter, cheaper package. Points come off only for the lower payload ceiling and the periodic error inherent to strain-wave gears.

Performance
85
Ease of use
90
Portability
98
Upgrade potential
80

Polaris weighs tracking and payload capability, how easy the mount 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.

Wide-field imagers running a small refractor or RedCat-class rig
Buy it if you
✓Wide-field imagers running a small refractor or RedCat-class rig
✓Travellers who count every gram toward getting to dark skies
✓Star-tracker owners ready to step up to a full GoTo, plate-solving imaging mount
Look elsewhere if you
!Anyone running a heavier SCT or long-focal-length system, step up to the AM5N
!Pure visual observers, a manual alt-az mount costs far less
!Budget-first beginners, a traditional equatorial mount gives more payload per dollar
05The numbers

Full specifications.

7 measured and stated values
Mount & drive
Payload Capacity8 kg
More
GoToYes
Finds objects from a built-in database and points the mount at them automatically, then tracks.
Head Weight3.6 kg
Imaging Payload8 kg
Mount TypeHarmonic (strain wave)
TrackingYes
A motor turns the mount at the sky’s speed, holding your target still for long exposures. You still aim it yourself.
weight lbs7.9lbs
Editor’s Take

The AM3N is the AM5N's lighter twin, with the same harmonic magic: strain-wave gears hold your scope with no counterweight, so a 3.6 kg head carries an 8 kg rig and you skip the balancing ritual. It is a full GoTo mount and plate-solves with a ZWO ASIAIR, centering targets by reading the star field. The one trade against the AM5N is payload headroom, 8 kg instead of 15, which is plenty for the small refractor and cooled camera it is built to travel with. If you know you will run heavier optics later, buy the AM5N; if grams to the dark site matter most, the AM3N is the pick.

— The Skynocular verdict