One axis against the turning sky — once it is aligned
An equatorial mount tilts one of its two axes until it points at the celestial pole, so that a single motor turning at one revolution a day cancels the rotation of the Earth. That is the whole idea, and it comes with the condition that the whole idea depends on: the mount only tracks if it is polar aligned. An equatorial head that has been set down without alignment is a worse alt-azimuth mount, and this is the single most common reason a first equatorial disappoints. The specification to read hardest is the payload rating. Makers publish it for visual use, and photography asks for a considerably wider margin, because a guiding error that is invisible at the eyepiece is a smeared star on a sensor. The rating also excludes the counterweights, and sometimes excludes the camera. Periodic error, when a maker publishes it, describes the repeating wobble that the worm gear introduces once per revolution; it is the figure that decides how long an unguided exposure can be. Then the parts that decide whether the mount is pleasant at one in the morning: whether a polar scope is fitted or optional, whether the latitude and azimuth adjusters move smoothly under load, what the tripod weighs, and how many separate pieces the whole thing becomes for the car. We compare payload rating, periodic error, drive and control, polar alignment provision, counterweight supply, tripod, heaviest single piece and supplied optics.
114 mm (4.49 in) mirror · 900 mm (35.4 in) focal length · f/7.9 · EQ-1 equatorial mount
Omegon's N 114/900 EQ-1: a 114/900 Newtonian on an EQ-1 equatorial mount with fine adjustment on both axes, a 1.25 in focuser, a finder with crosshairs and 25 mm and 10 mm eyepieces.
Best for: A first equatorial telescope for the Moon and planets
≈ $387
20 lb (9.07 kg) payload · 12.5 lb mount · 33 to 47 in · 1.75 in stainless steel legs · 7 lb and 4 lb counterweights
Celestron's CG-4: a manual German equatorial mount with slow-motion controls and ball bearings on both axes, a 20 lb payload, 7 lb and 4 lb counterweights and a stainless steel tripod with 1.75 in legs.
Best for: A tube of up to 20 lb, followed by hand on a tripod that does not shake
≈ $420
GoTo equatorial · belt-driven clutched worm gears · polar sight hole through the RA axis · ExploreStars app · eight CPUs claimed
Explore Scientific's iEXOS-100-2: a GoTo equatorial mount and tripod with clutched dual-axis worm gears on belt-driven stepper motors, the PMC-Eight controller, the ExploreStars app and a polar sight hole.
Best for: A small imaging setup that has to be polar-aligned quickly and driven from a tablet
≈ $300
The stated tripod describes what the maker supplies under the mount. This site judges no stability.
The heaviest single piece decides whether one person can set the whole thing up. Head and counterweights travel separately.
Because one axis then suffices to compensate the sky’s rotation. That is what makes long exposure possible.
The mass the maker states for the mount. This site reports it and does not present it as a safe load for a given setup.
The repeating deviation of the drive, published in arcseconds. It shows mostly in photography at long focal length.
The nature of the mechanism turning the axis. It is published and explains part of the noise and of the precision.
It is published entry by entry. Without a suitable counterweight, balancing is impossible.
That depends on the published provision and on the precision sought. This site publishes no measured duration.
The driving methods accepted, published by the maker. They decide what can be automated.
Published periodic error and payload rating are the two figures to read. This site describes no photographic setup.
An equatorial mount is read on what it carries without shaking and on how smoothly it drives. The heaviest single piece decides whether it ever leaves the garage.
The column is shown only when four instruments in five publish the figure. Below that, it would be comparing the absence of numbers.
| Model | Price | Control | Drive | Supplied optics |
|---|---|---|---|---|
| Explore Scientific iEXOS-100-2 PMC-Eight (ES-iEXOS-100-02) | $300 | PMC-Eight controller, described as eight independent CPUs · ExploreStars app for Apple, Android and Windows tablets | Clutched dual-axis worm gears with quiet stepper motor belt drives, stated | None: this is a mount and tripod |
| Omegon N 114/900 EQ-1 | $387 | Fine adjustment in declination and right ascension, stated | None as sold · stated refittable with an electronic tracking motor | Newtonian reflector, 114 mm (4.49 in) mirror, 900 mm (35.4 in) focal length, f/7.9 · 1.25 in focuser with focus wheel · finder with crosshairs · 25 mm eyepiece (36x) and 10 mm eyepiece (90x) |
| Celestron CG-4 manual German equatorial (91509) | $420 | Manual slow-motion knobs on right ascension and declination | None: manual slow-motion controls on both axes · ball bearings in both axes, stated | None: this is a mount and tripod |
Specifications: manufacturer sheets for telescopes and observing optics and the matching Amazon product pages. Prices and availability: Keepa. Every figure in this table names its source.
Most recent revision in this category: November 7, 2026.
Any figure written into the body of this page was true on the day it was written. The amount shown next to each instrument is requested from the retailer as the page loads, and it is that amount, not the text, that stands.
