ZWO Astronomy Cameras

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 days

Price tracked by PolarisObserved 50 timesTracking since Jul 2026

Where to buy

Agena AstroProductsPartnerBest price$1,499→High Point ScientificCheck price→

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01What it's good at

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

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.

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.

02The Polaris Score

How it scores, and why.

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

Ease of use

Portability

Upgrade potential

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.

03Who it's for

An honest fit check.

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.

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