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Diagonals & Accessories

Items 51 - 75 of 88

Baader 2" 90-Degree Erecting Amici Prism Diagonal with 1.25" Adapter

SKU: BAD-AMICI-2
  • Diagonal Type: Correct/Erect Image
  • Diagonal Size - Eyepiece Side: 2" Barrel
  • Diagonal Size - Telescope Side: 2" Barrel
  • Includes Eyepiece Adapter: Yes, 2" to 1.25"
  • Optics Type and/or Coatings: 7-Layer Multi-Coating , Amici Prism
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$299.00
 
William Optics 1.25" Dura Bright Digaonal for Star71 Refractor

William Optics 1.25" Dura-Bright Diagonal for Star71 Telescope - D-125D-WO71

SKU: WYO-D-125D-WO71
  • Diagonal Type: Mirror Diagonal
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: M65x1 Male Thread
  • Optics Type and/or Coatings: DuraBright Coatings
$135.00
 
William Optics 2" to 1.25" RotoLock Adapter

William Optics 2" to 1.25" RotoLock Adapter - Gold - F-ROTO-A2-125GD

SKU: WYO-F-ROTO-A2-125GD
  • This Rotolock adapter locks into the 2” opening of a WO Rotolock diagonal or focuser.
  • This is a steppingstone to attaching 1.25” barreled accessories.
  • Rotating the adapter ring will lock and unlock the inserted accessory into place.
  • Using this adapter will ensure that your accessory is centered.
$45.00
 
William Optics RotoLock Eyepiece Adapter & Visual Back for 2 WO Diagonals

William Optics RotoLock Upgrade for WO 2" Diagonals - D-ROTO-A2

SKU: WYO-D-ROTO-A2
  • This Rotolock upgrade uses a flange to connect to WO 2" Diagonals.

  • Rotating the ring with lock and unlock the accessories in place.

  • No thumbscrews are used, so users do not have to worry about marring.

  • William Optics' Rotolock upgrade comes with a plastic protective dust cover.
$89.00
 
Baader Clicklock 2" to 1.25" Reducer Adapter

Baader Clicklock 2" to 1.25" Reducer - T2-15B

SKU: BAD-T2-15B
  • The Clicklock reducer from Baader holds 1.25” eyepieces.

  • A 20-degree twist of the knurled outer ring will lock and unlock the eyepieces in place.

  • A Clamp Lever is included to indicate clamp position.

  • The reducer is made from hardened bronze.
$89.00
 
Baader Planetarium T2 90º Prism Star Diagonal with 1.25" Nosepiece and 1.25" Eyepiece Holder

Baader T-2 90º Prism Star Diagonal with 1.25" Nosepiece & Eyepiece Holder - PRISM-1

SKU: BAD-PRISM-1
  • Diagonal Type: Prism Diagonal
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: 1.25" Barrel
  • Optics Type and/or Coatings: 7-Layer Multi-Coating
$169.00
 
Baader 2" Zeiss Prism Star Diagonal with BBHS Coatings & 2" ClickLock Eyepiece Holder

Baader Planetarium 2" Zeiss Prism Star Diagonal with BBHS Coatings & 2" ClickLock Eyepiece Clamp - PRISM-2Z

SKU: BAD-PRISM-2Z
  • Diagonal Type: Prism Diagonal
  • Diagonal Size - Eyepiece Side: 2" Barrel
  • Diagonal Size - Telescope Side: 2" Barrel
  • Includes Eyepiece Adapter: No, 1.25" Eyepiece Adapter Sold Separately
  • Optics Type and/or Coatings: BBHS Coatings , Zeiss Optics
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$539.00
 
Baader Planetarium T2 90º Star Diagonal Zeiss Prism

Baader T2 90º Star Diagonal Housing - Zeiss Prism, 34mm Clear Aperture - T2-01B

SKU: BAD-T2-01B
  • Diagonal Type: Prism Diagonal
  • Diagonal Size - Eyepiece Side: T-2 Threads
  • Diagonal Size - Telescope Side: T-2 Threads
  • Optics Type and/or Coatings: 7-Layer Multi-Coating , Zeiss Optics
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$272.00
 
Baader Planetarium T2 90º Prism Diagonal Housing - 32 mm Clear Aperture

Baader T2 90º Prism Diagonal Housing - 32mm Clear Aperture - T2-01C

SKU: BAD-T2-01C
  • Diagonal Type: Prism Diagonal
  • Diagonal Size - Eyepiece Side: T-2 Threads
  • Diagonal Size - Telescope Side: T-2 Threads
  • Optics Type and/or Coatings: 7-Layer Multi-Coating
$129.00
 
Takahashi 10th Wave 2" Diagonal

Takahashi 1/10th Wave 2" Diagonal with 1.25" Adapter - TKA00543

SKU: TAK-TKA00543
  • Diagonal Type: Mirror Diagonal
  • Diagonal Size - Eyepiece Side: 2" Barrel
  • Diagonal Size - Telescope Side: 2" Barrel
  • Includes Eyepiece Adapter: Yes, 2" to 1.25"
  • Optics Type and/or Coatings: Enhanced Aluminum Coatings
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$540.00
 
Takahashi 1.25" Prism Diagonal

Takahashi 1.25" Prism Diagonal - TKA00547

SKU: TAK-TKA00547
  • Diagonal Type: Prism Diagonal
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: 1.25" Barrel
$147.00
 
Takahashi Short 2" Visual Adapter

Takahashi 2" Visual Adapter - TKP27110S

SKU: TAK-TKP27110S
  • One side of the Visual Adapter threads onto the 8L Coupling from Takahashi.

  • The other side of the adapter accepts a variety of adapter and accessories.

  • This adapter is compatible with Takahashi's Sky 90.

  • It can be used with the FSQ-85, and FSQ-106EDX when certain accessories are used in conjunction.
$177.00
 
TeleVue 90º Enhanced Diagonal - 1.25"

Tele Vue 90º Enhanced Aluminum Diagonal - 1.25" - DSC-0125

SKU: TLV-DSC-0125
  • Diagonal Type: Mirror Diagonal
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: 1.25" Barrel
  • Optics Type and/or Coatings: Enhanced Aluminum Coatings
$132.00
 
TeleVue 90º Enhanced Mirror Diagonal - 2"

Tele Vue 90º Enhanced Aluminum Diagonal - 2" - DSC-8001

SKU: TLV-DSC-8001
  • Diagonal Type: Mirror Diagonal
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: 1.25" Barrel
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$216.00
 
Baader 1.25" 45º Maxbright Amici Erecting Prism

Baader 1.25" Maxbright Amici 45º Erecting Prism with Integrated 2X Glass Path Corrector - MAXAMICI

SKU: BAD-MAXAMICI
  • Diagonal Type: Correct/Erect Image
  • Diagonal Size - Eyepiece Side: T-2 Threads
  • Diagonal Size - Telescope Side: 1.25" Barrel
  • Optics Type and/or Coatings: Amici Prism , Maxbright Coatings
$115.00 $92.00
 
Baader Planetarium 2" to 1.25" Pushfix T2 Thread Reducer

Baader Planetarium 2" to 1.25" Pushfix T-2 Thread Reducer - T2-15A

SKU: BAD-T2-15A
  • This thread reducer only has 1 mm optical path length.

  • The Pushfix reducer has three methods of attaching 1.25" accessories.

  • Baader has designed this reducer to work best with Newtonian Focusers.

  • With Countersunk Delrin grub screws, this reducer enables correct pressure.
$43.00
 
William Optics SCT RotoLock Adapter & Visual Back - 1.25"

William Optics 1.25" SCT RotoLock Adapter & Visual Back - F-ROTO-A2-125-SCT-TA

SKU: WYO-F-ROTO-A2-125-SCT-TA
  • One side of this adapter has an SCT thread and the other has a standard 1.25" Rotolock visual back.

  • Simply rotating the adapter will unlock and lock the inserted accessory into place.

  • The design of the adapter will firmly hold and center the accessory.

  • William Optics has utilized internal ball bearings and detents in this design.
$79.00
 
William Optics Blue 2" to 1.25" RotoLock Adapter

William Optics 2" to 1.25" RotoLock Adapter - Blue - F-ROTO-A2-125BU

SKU: WYO-F-ROTO-A2-125BU
  • This adapter connects to a 2" diameter opening to allow for the use of 1.25" accessories.

  • William Optics designed this adapter to work with WO RotoLock diagonal or focuser.

  • Rotating the adapter ring will lock and unlock the inserted accessories into place.

  • The design ensures a tight grip and optimum centering.

  • This adapter is anodized blue.
$45.00
 
William Optics 2" to 1.25" RotoLock Adapter - Red Version

William Optics 2" to 1.25" RotoLock Adapter - Red - F-ROTO-A2-125RD

SKU: WYO-F-ROTO-A2-125RD
  • This adapter connects to a 2" diameter opening to allow for the use of 1.25" accessories.

  • William Optics designed this adapter to work with WO RotoLock diagonal or focuser.

  • Rotating the adapter ring will lock and unlock the inserted accessories into place.

  • The design ensures a tight grip and optimum centering.

  • This adapter is anodized red.
$45.00
 

Baader 1.25" Amici 45º Erecting Prism w/24 mm Clear Aperture - AMICI-45

SKU: BAD-AMICI-45
  • Diagonal Type: Correct/Erect Image
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: 1.25" Barrel
  • Optics Type and/or Coatings: Amici Prism
$92.00
 
Baader Planetarium 2" Amici 45º Erect Prism with 2" SCT Thread & 2" to 1.25" Reducer

Baader 2" Amici 45º Erecting Prism w/2" SCT Thread - AMICI-45-2

SKU: BAD-AMICI-45-2
  • Diagonal Type: Correct/Erect Image
  • Diagonal Size - Eyepiece Side: 2" Barrel
  • Diagonal Size - Telescope Side: SCT Threads
  • Includes Eyepiece Adapter: Yes, 2" to 1.25"
  • Optics Type and/or Coatings: Amici Prism
Free shipping Free shipping
$239.00
 
Baader Planetarium 2" 90º Astro Amici Diagonal Prism with BBHS Coating

Baader 2" Astro Amici 90º Diagonal Prism with BBHS® Coating - AMICI-DX2

SKU: BAD-AMICI-DX2
  • Diagonal Type: Correct/Erect Image
  • Diagonal Size - Eyepiece Side: 2" Barrel
  • Diagonal Size - Telescope Side: 2" Barrel
  • Includes Eyepiece Adapter: No, 1.25" Eyepiece Adapter Sold Separately
  • Optics Type and/or Coatings: Amici Prism , BBHS Coatings
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$719.00
 
Takahashi 1.25" Eyepiece Holder

Takahashi 1.25" Compression Ring Ocular Adapter - TKP00101

SKU: TAK-TKP00101
  • The 1.25" Ocular Adapter is for 1.25" eyepieces and diagonals.

  • Takahashi has designed the adapter a two-point compression ring and chrome set-screws.

  • One side will thread into the 2" opening of the Coupling S Adapter from Takahashi.

  • The provided 1.25" sleeve will accept a 1.25" diagonal or eyepiece.
$89.00
 
Takahashi Coupling S - TKP00103

Takahashi Coupling S for Visual - TKP00103

SKU: TAK-TKP00103
  • On the telescope side, this adapter will connect to TKP86005 Visual Adapter or the 50.8 mm Sleeve from Takahashi.

  • One the other side, the Coupling S will connect to the 1.25" Ocular Adapter, which will then accept a 1.25" diagonal or eyepiece.

  • Takahashi's TCE0100 Collimating Scope will thread onto this adapter, which then connects to the focuser drawtube.

  • Using this adapter with the collimating scope will let you use the scope with Tak refractors that have a focal length of at least 1000 mm.
$52.00
 
Takahashi 50.8mm Sleeve - TKP00113

Takahashi 2" Sleeve to 1.25" Adapter - TKP00113

SKU: TAK-TKP00113
  • This sleeve adapter connects to the Coupling S on the eyepiece side.

  • On the telescope side, the sleeve adapter connects to the 2" Eyepiece Holder or the 50.8 mm Extension Tube.

  • This part serves as an alternative for the TCN0055 adapter.

  • With this sleeve you can connect the 1.25" Ocular Adapter, view through a 1.25" eyepiece, or insert a 1.25" diagonal.
$47.00
 

A star diagonal is a useful astronomy accessory because it allows viewers to look through their telescope perpendicular to the direction the telescope points or at a 45° angle. This makes diagonals handy for terrestrial observations as well. The people at High Point Scientific understand that the comfort and convenience of using a star diagonal is important to you, that is why we offer many different types of telescope diagonals for you to choose from. You will find the latest brands offering a variety of diagonals, including mirror, dielectric, and prism diagonals.


As the name suggests, mirror diagonals use a mirror to turn the telescope’s image at a 90° or 45° angle. This creates an image that is correctly oriented vertically but reversed horizontally. The mirror is typically made of silver or aluminum, both of which scratch easily. You will need to careful when cleaning and using your mirror diagonal. However, mirror diagonals are often very affordable which makes them a favorite among amateur astronomers.


Many astronomers prefer mirror diagonals but wish they were more durable. That’s why High Point Scientific also offers dielectric diagonals. Dielectric diagonals are mirror diagonals but include enhanced dielectric coatings for greater durability and reflectivity. These coatings make dielectric diagonals hard and sturdy so it is much more difficult to scratch or mar mirror surfaces.


Prism diagonals are often considered the most innovative design for a diagonal. They use a glass prism that often produces higher reflectivity than mirror or dielectric diagonals. This means that prism diagonals suffer minimal light loss to give you high contrast celestial views. Be sure to look for Amici prism diagonals on the High Point Scientific website, as these produce an upright image with a correct left-right view for low-powered eyepieces.

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