How they move: Up/down and left/right
Great for:
Visual observing
Planetary video
EAA (near-real-time viewing)
Hard limit: Field rotation → not suitable for long-exposure deep-sky imaging.
Key idea:
Alt-Az mounts track position, not the sky’s rotation.
How they move: Aligned to Earth’s rotation axis
Why they matter:
Track the sky with a single axis
Eliminate field rotation
Required for:
Long-exposure deep-sky imaging
Precise, repeatable tracking
(Star Adventurer, SkyGuider, etc.)
What they are: Lightweight EQ mounts with RA-only tracking
Designed for:
DSLR + lenses
Wide-field imaging
Fast, portable setups
Limitations:
No DEC correction (or manual only)
High periodic error
Very sensitive to payload balance
Important truth (no hype):
Trackers are limited by mechanics (PE), not polar-alignment skill.
(HEQ5 / EQ6 class)
What you gain:
RA + DEC motors
Much lower periodic error
Consistent, predictable tracking
Designed for:
Telescopes
Autoguiding
Longer focal lengths and longer subs
Trade-off:
Heavier, slower to set up, higher cost — but reliable results.
Key features:
Extremely compact
High payload-to-weight ratio
Very stiff mechanically
Reality check:
Very high raw periodic error
Designed to be guided at all times
Poor unguided performance
Expensive relative to German Equatorial
Key framing:
Harmonic mounts trade mechanical smoothness for stiffness and software correction.
Use case
Best mount type
Visual / planets
Alt-Az
DSLR wide-field
EQ tracker
Telescopes / long subs
Full EQ mount
Portable + guided
Strain-wave