Star diagonals are important devices that divert the path of the beam of light coming from the telescope so that you do not have to strain to see, but can view comfortably and hence enjoy your observing more. The star diagonal’s prism deflects the light by 90°. Refractors, Schmidt-Cassegrain and Maksutov optics often need this device.
Amici prisms divert the light, usually by 45° or even 90°, providing an upright and non-reversed image for terrestrial observing.
Optical design & connection
Top brands

Omegon
Carbonline 2'', 90° SC mirror star diagonal, 99% dielectric
$ 199.00
ready for shipping in 24
h

Omegon
Amici-Prisma 90°, 1,25''
( 5 / 5 )
$ 29.90
ready for shipping in 24
h

Omegon
Carbonline 2", 90° mirror star diagonal, 99% dielectric
$ 199.00
ready for shipping in 24
h

Omegon
1,25'' Amici Prism 90°
( 5 / 5 )
$ 169.00
ready for shipping in 24
h

Omegon
Star diagonal with 99% reflection, 2"
( 5 / 5 )
$ 219.00
ready for shipping in 24
h

Omegon
Carbonline 1.25'', 90° mirror star diagonal, 99% dielectric
$ 139.00
ready for shipping in 24
h

Omegon
Mirror star diagonal, 90°, 1.25"
$ 29.90
ready for shipping in 24
h

Baader
Diagonal mirror ClickLock 2"
( 5 / 5 )
$ 306.00
ready for shipping in 1-2
weeks

Seben
Zenitprisma 90° AP3 1,25''
$ 12.90
Sale price:
$ 10.22
ready for shipping in 24
h

Omegon
2'', 45° Amici prism
$ 199.00
ready for shipping in 24
h

Omegon
1.25" 45° erecting prism
$ 44.90
ready for shipping in 24
h
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Omegon
Amici prism 90° 2"
$ 269.00
ready for shipping in 24
h

Bresser
Star diagonal 99 Percent Reflectivity 2"
$ 82.00
ready for shipping in 1-2
weeks

Baader
Zenith prism T-2/90 degree, 32mm
$ 141.00
ready for shipping in 24
h

Celestron
zenith prism 90°, 1.25"
( 5 / 5 )
$ 43.90
ready for shipping in 24
h

Baader
Diagonal prism 2" ClickLock BBHS®
$ 530.00
ready for shipping in 1-2
weeks

Omegon
Pro Penta Prisma 90° 1.25''
$ 239.00
ready for shipping in 24
h

APM
Diagonal mirror 90° 99% 2"
$ 130.00
ready for shipping in 1-2
weeks

William Optics
Diagonal mirror Dura Bright 90° 2"
$ 237.00
ready for shipping in 3-5
weeks

Baader
2" BBHS®-Click-Lock mirror star diagonal
$ 495.00
ready for shipping in 1-2
weeks

Celestron
Diagonal mirror Twist-Lock 2"
$ 340.00
ready for shipping in 1-2
weeks

TS Optics
Diagonal mirror 90° 1.25"
$ 119.00
ready for shipping in 3-7
days

Omegon
45°, 2'' to 1.25'' Amici prism
$ 219.00
ready for shipping in 24
h

TS Optics
Diagonal mirror 90°, dielectric full coating, 2'' Quartzprotection
$ 206.00
ready for shipping in 3-7
days

TS Optics
Diagonal prism T2 90°
$ 92.00
ready for shipping in 24
h

APM
Star diagonal 99 Percent Reflectivity 2"
$ 185.00
ready for shipping in 1-2
weeks

Artesky
Diagonal mirror 90° 1.25"
( 5 / 5 )
$ 78.00
ready for shipping in 3-5
weeks

Skywatcher
Amici prism 90° 1,25"
$ 58.00
Product can be shipped as of 01.03.2025

Celestron
Amici prism 45°, 1.25''
$ 51.00
ready for shipping in 24
h

Baader
Amici prism ClickLock BBHS® 90° 2"
$ 700.00
ready for shipping in 1-2
weeks

Bresser
Amici Prisma 45° 1.25''
$ 51.00
ready for shipping in 24
h

Explore Scientific
3" 90° mirror star diagonal
$ 600.00
ready for shipping in 24
h

William Optics
Dura Bright 1.25" 90° mirror star diagonal
$ 185.00
ready for shipping in 24
h

Baader
Amici prism 90° 2"
$ 302.00
ready for shipping in 1-2
weeks

Omegon
Pro 1.25'', 45° penta-prism
$ 189.00
ready for shipping in 24
h

Bresser
Amici prism 90° 1,25"
$ 51.00
ready for shipping in 1-2
weeks