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Theia90 Collimating Star Diagonal and Filter Changer

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The Theia90 1/10th wave star diagonal is a combined star diagonal and filter changer, with a micro meter tip / tilt adjustable mirror.

Box Contents:

  • Theia90 1/10th wave mirror star diagonal body
  • Light baffled nose
  • 3 x 2″ magnetic filter holders
  • Zygo report
  • Instructions
  • Mini Cerberus case

The all new Theia 90 1/10th Wave Star Diagonal is now available. Load up your filters in advance into our quick change filter holders and you can rapidly swap from one filter to another. Using high power magnets to hold the filters in place you can meridian flip the telescope and not drop the filters. When you want to change you simply pull the filter out and replace it.

 Theia 90 1/10th wave Star DiagonalTheia 90 1/10th wave Star Diagonal

The diagonal uses a 46mm minor axis mirror with 1/10th wave finish and each unit comes with an individual Zygo report so you can be sure of its quality.

Using the 4 screws on the back the position of the mirror can be altered to help collimate your telescope. The unit comes in a sturdy mini cerberus case which is just a tough as its larger brother.


Astronomy Now Review:

The diagonals mirror is of excellent quality, and observational comparison with one or two of my own diagonals gave me no cause to doubt that the 46mm (minor axis) mirror is as stated, one-tenth wave with 99 per cent reflectance.

The beauty of this system is that filters can be placed in this primary optical position, doing their task unmoved for any eyepiece or camera changes ‘downwind’.

True to its makers’ name, this diagonal is a precisely made piece of astronomical engineering, and I have no hesitation in recommending it.


Specifications: Theia90 Collimating Star Diagonal and Filter Changer

What's in the Box

What's in the Box: Theia90 Collimating Star Diagonal and Filter Changer

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