9.1
Koolpte
Black 90mm refractor telescope for deep sky
$250
Black For adults Refractor Altazimuth mounts 90mm aperture For deep sky
Telescopes / 900mm focal length
This group
900mm Telescopes
Checked 2026-10-24
Extended focal lengths for serious high-power astronomical observation 9 telescopes · 8 brands
For adults
For beginners
For kids
Refractor
For moon viewing
Portable
Tripod included
For travel
Budget
With phone adapter
Altazimuth mounts
90mm aperture
80mm aperture
Equatorial mounts
Reflector
70mm aperture
Professional
For bird watching
For deep sky
For astrophotography
600mm focal length
Black
Smart
Digital
Dobsonian
800mm focal length
Monocular
400mm focal length
White
50mm aperture
STEM learning
Tabletop mounts
Maksutov-Cassegrain
130mm aperture
60mm aperture
900mm focal length
114mm aperture
300mm focal length
Blue
Waterproof
700mm focal length
Red
Green
Best 900mm Telescopes
9.1
9.1
Celticbird
Portable travel refractor with 900mm focal length
$140
For adults For beginners Refractor Portable For travel Altazimuth mounts
9.0
SOLOMARK
Long focal length 80mm refractor with AZ mount
$69.99
For adults For beginners Altazimuth mounts 80mm aperture Professional
8.8
SOLOMARK
Portable 80mm refractor telescope with 900mm focal length
$69.99
For adults For beginners Refractor Portable With phone adapter 80mm aperture
8.6
HETEKAN
High powered 90mm refractor with 900mm length
$240
For adults For beginners Refractor For kids For moon viewing 90mm aperture
8.5
Hawkko
Professional 90mm aperture refractor with 900mm focal length
$240
For adults For beginners Refractor For moon viewing With phone adapter Altazimuth mounts
7.8
FlyGala
Professional 900mm focal length 80mm refractor
$145
For adults For beginners Refractor Tripod included With phone adapter 80mm aperture
7.3
Ningbo Zhanjing OpticalInstruments
Refractor telescope with 102mm aperture for precise tracking
$300
For adults For moon viewing Professional For deep sky
7.5
GALAEYES
White metal altazimuth smart refractor 900mm
For adults For beginners For kids Altazimuth mounts Smart White
Before you buy
900mm telescope questions
What can I see with a 900mm focal length telescope?
The moon and planets are the main targets, with enough magnification to show craters and cloud bands. Bright double stars and some globular clusters are also within reach, but wide deep-sky objects are framed too tightly for a good view.
Is a 900mm refractor good for beginners?
Yes, if you want higher magnification for lunar and planetary viewing. The longer tube is less forgiving of a shaky mount, so a stable tripod and slow-motion controls make a real difference in use.
How does 900mm compare with 600mm or 800mm focal lengths?
A 900mm focal length gives more magnification and a narrower field than 600mm or 800mm. That helps on the moon and planets but makes it harder to fit large star clusters or nebulae in the eyepiece.
Do 900mm telescopes come with a tripod?
Many are sold as complete kits with an altazimuth tripod, a finder, and one or more eyepieces. Some include a carry bag and a phone adapter, while others are optical tubes only and need a separate mount.
A longer focal length for higher magnification
A 900mm focal length gives a narrower field of view and more magnification for a given eyepiece, which suits the moon, planets, and double stars. These telescopes are often refractors with apertures around 80mm to 102mm, mounted on altazimuth tripods. The longer tube makes them less compact than short-tube designs, but the extra reach is the point.
How these telescopes are built
Most are achromatic refractors with multi-coated optics and a rack-and-pinion or helical focuser. The tubes are commonly black or white and sit on an altazimuth mount with slow-motion controls. Some include dual slow-motion rods for smoother tracking at high power, and a few come with a carry bag and phone adapter.
Mount and accessory details that matter
The mount is often the weak point on a long refractor, so look for a tripod with adjustable legs and a head that does not wobble when you touch the focuser. Slow-motion controls on both axes help you keep a target centered at high magnification. A finderscope is important because the narrow field makes star-hopping harder without one.
What to expect at the eyepiece
With an 80mm or 90mm aperture at 900mm focal length, the moon shows crisp craters and the planets show small disks with some detail. The field of view is tight, so wide star fields and large nebulae are less impressive than they would be in a shorter telescope. A 102mm version gathers more light and resolves finer detail, but the tube is heavier and demands a sturdier mount.