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Apertura 45-Degree Prism Diagonal - 1.25"

(6 Available)
Free shipping
SKU: APT-A-P45
$29.95
 
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Add Dual Functionality to Your Telescope!

Expand your telescope's capabilities and increase viewing comfort with this diagonal from Apertura! With image orientation correcting optics built-in you'll transform your night sky observing instrument into a daytime viewing scope, with a wider angle prism to help with comfort on straight-through focuser telescopes. Read on to learn more about how the excellent Apertura 45-Degree Prism Diagonal - 1.25" add-on can easily increase the utility of your scope!

For those looking to bring their observations back down to Earth, make manual movements feel more natural, or find a comfortable angle, this 1.25" Apertura 45-Degree Prism Diagonal is the tool for you! If you looked through your scope during the day, chances are good that the image projected through your eyepiece is upside down making daytime observations of distant landmarks, wildlife, and scenery a disorienting experience. With this diagonal installed in your scope you can set objects the 'right way around' and take in the beauty our universe has to offer after the Sun has risen! These views are clearly rendered in your eyepiece thanks to the fully-coated prism; and with its 45° design, you can find a middle ground between the neck-straining angles 90° diagonals or straight-through viewing can create in some scenarios. This angled design matches particularly well refractors and SCTs for this reason—and with the 1.25" telescope connection as well as eyepiece holder, compatibility with those telescopes and your observing equipment is excellent! The Apertura 45-Degree Prism Diagonal is more than just a daytime observing accessory, able to bring you stellar views of the stars as well and help make manual movements feel more natural.

Quality and Comfortable Viewing, Day or Night

The Apertura 45-Degree Prism Diagonal gives you a quality viewing experience suited for both terrestrial and celestial use, in an 1.25" housing and backed by an industry leading warranty!

45° Prism
When observing during the day your scope will generally sit at more horizontal (lower) angles compared to night-time observing, making typical 90° diagonals a bit less comfortable to use. However straight-through viewing can still cause strain for some, which is where this diagonal's angle comes in! With a 45° prism this dual function diagonal will help you find a comfortable "middle ground" for day and night viewing alike!

Erecting Image Design
Apertura has built this diagonal with "image erect" optics, turning your images right-side up and non-reversed. This allows you to use your scope during the day for observing faraway objects in crisp, correctly oriented, detail! In addition to expanding your telescope's capabilities, this built-in optical image correction can make your night sky observation experience feel more intuitive as well! While objects in the night sky don't necessarily have a "correct" orientation, an upsidedown perspective can make moving a particular feature to the center of your view a disorienting experience—but with the Apertura 45-Degree Prism Diagonal installed in your scope manual movement of your scope will feel more natural!

Efficient Design
The Apertura 45-Degree Prism Diagonal has been designed for 1.25" connections, with the telescope focuser barrel and visual accessory holder being built to this standard. This makes the diagonal widely compatible with most focusers on the market today, able to interface with 2" focusers through commonly available 1.25" to 2" adapters, as well as a wide variety of eyepieces and Barlows. For visual filter users, this diagonal is additionally threaded for the common 1.25" filter size on the 1.25". This effective physical design has been combined with quality coated optical components to deliver you great performance!

Comes with the Apertura Absolute Warranty
The Apertura Absolute Warranty provides two years of coverage against product defects. After the initial two-year warranty expires, this product qualifies for Apertura's Three-Year Accident Replacement Program. In addition, the Apertura Absolute Warranty is transferable! Download a copy of the Apertura Absolute Warranty for more information on this program, how to make a claim, and why it is important to keep your original receipt and the product's original boxes and packaging!