1.25" Prism diagonal


Availability: More on the way

This premium 1.25" Takahashi TAKSD1 compression ring prism star diagonal is the diagonal that Takahashi puts with all of their complete telescope systems - even those costing as much as $30,000.
Our Product #: TAKSD1

Product Description

This Takahashi TAKSD1 premium 1.25" star diagonal uses a high quality prism instead of a mirror. The prism has 100% internal reflectivity and the entry and exit faces of the prism are multicoated for minimum light loss. The lightweight (only 3 ounce) diagonal will work with any 1.25" accessory telescope other then a reflector.

The diagonal uses a non-marring molded compression ring to hold the eyepiece in place, rather than a set screw that can scratch the barrels of your eyepieces. The compression ring is tightened by a ribbed thread-on collet around the eyepiece holder. Rotate the collet in one direction and the compression ring tightens on the eyepiece to hold it firmly in place. A simple twist on the collet in the opposite direction loosens the compression ring's grip on the eyepiece. With a collet, instead of a thumbscrew as most diagonals use, there is no chance of losing the thumbscrew in the dark (along with the ability to hold your eyepieces safely in your diagonal).

The Takahashi TAKSD-1 is standard equipment with every Takahashi complete telescope package. Do you think that Takahashi would limit the performance of their telescope systems costing up to $30,000 with a less than exceptional star diagonal? Takahashi wanted the best 1.25" diagonal for their telescopes. Should you settle for anything less than the best for your scope?

Tech Details

Weight 3 oz.
Warranty 5 years


Review by:
Don’t let the plastic body dissuade you this is a finely made prism diagonal at a great Price! (Posted on 11/16/2018)
Review by:
This is my everyday diagonal for a five-inch triplet refractor (actually, I have two - I like having back-ups). This is a quality item from a manufacturer who can justly be called the Japanese Zeiss, and at a surprising low price. If you do your research online, you'll find that this prism diagonal is in the top echelon of diagonals and outperforms many highly-regarded mirror diagonals, especially in planetary work (talking especially about Jupiter). Buy it - it's a steal. (Posted on 8/4/2017)
How do you rate this product? *