Ever wondered if your telescope can double up for daytime use as well as stargazing? Well, if you own a refractor or a Schmidt-Cassegrain telescope (a popular type of catadioptric telescope), you're in luck! The most impactful accessory you can invest in for terrestrial viewing is an erect-image diagonal.

With a standard mirror or star diagonal in place, you'll find that the images you see might be upside down, mirrored, or both. While this might not be an issue when you're gazing at celestial objects, it can be quite disorienting when you're watching a boat sail by or tracking an eagle soaring to its perch.

The fix? It's simple. Remove the existing diagonal from your telescope’s focuser or visual back and pop in the Celestron 45-Degree Erect Image Diagonal. Once you've done that and added an eyepiece, you'll find that the images appear as they should—right side up and left-to-right accurate. The 45-degree angle of this Amici prism diagonal is especially designed for comfortable viewing during daytime, often when your telescope is in a horizontal alignment.

A quick heads-up: If you've got a Newtonian reflector telescope, adding an erect-image diagonal won't correct the image orientation. Due to the unique optical design of Newtonian telescopes, the images will always appear slightly rotated. While you can still use it for daytime viewing, be prepared for a somewhat unconventional perspective.

Specifications

• A great accessory for daytime terrestrial viewing with your telescope
• This 1.25” diagonal produces right side up and left-to-right correct images when used with refractors and catadioptric (Schmidt-Cassegrain) telescopes
• Inserts into 1.25” focusers or visual backs; accepts standard 1.25” eyepieces