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SVBONY SV188 90° Zenith Mirror Diagonal - 1.25"

SVBONY SV188 90° Zenith Mirror Diagonal - 1.25"

par SVBONY
UGC SV-F9171A
CA$34.00 - CA$34.00
CA$34.00
CA$34.00 - CA$34.00
CA$34.00
Égalisation de prix!
  • Provides a comfortable 90-degree viewing angle
  • Standard 1.25" barrel fits most refractor and SCT focusers
  • Features a 90% reflectivity mirror for bright images
  • Durable all-metal housing maintains optical alignment
  • Single-screw clamp secures 1.25" eyepieces
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • SVBONY SV188 Zenith Mirror Diagonal 1.25inch 90 Degree

    The SVBONY SV188 Zenith Mirror Diagonal redirects the light path of your refractor telescope by 90 degrees, placing the eyepiece in a much more comfortable position for astronomical viewing. Its standard 1.25-inch barrel ensures compatibility with a vast range of telescopes and eyepieces, while the internal mirror's 90% reflectivity preserves the brightness and clarity of the image delivered by your objective lens.

    90% Reflectivity Mirror for Brighter, Clearer Views

    The core of the SV188 is its mirror, which features a reflective coating that transmits 90% of the incoming light to your eyepiece. This level of reflectivity is crucial for preserving image brightness, especially when observing faint deep-sky objects like the Orion Nebula (M42) or distant galaxies. Unlike some entry-level prisms, a mirror diagonal introduces no chromatic aberration, ensuring that bright objects like Jupiter and Sirius remain free of false color.

    Durable Metal Housing & 1.25" Refractor Compatibility

    Built with a metal housing, the SVBONY SV188 is designed for durability and to hold the mirror in precise alignment, night after night. The 1.25-inch nosepiece and eyepiece holder are standard sizes, ensuring a secure fit in the focusers of most refractors, Schmidt-Cassegrains, and Maksutov-Cassegrains. A single locking screw provides a firm grip on your eyepieces.

    • Refractor-Specific Design: This diagonal is optimized for telescopes where you view from the back of the tube.
    • Newtonian Limitation: The SV188 is not suitable for Newtonian reflectors. Its light path is too long, which prevents the telescope from reaching focus.

    SV188 Mirror vs. Prism Diagonal: A 90° Difference

    While both mirror and prism diagonals provide a 90-degree viewing angle, they achieve it differently. The SV188's mirror reflects the light, which generally provides better color fidelity and light throughput compared to standard, uncoated prism diagonals. While high-end prisms can offer excellent views, a quality mirror diagonal like the SV188 is often a significant upgrade over the basic prism included with many beginner telescopes, yielding sharper and brighter images.

  • Why should I use the SVBONY SV188 diagonal with my refractor?

    The primary reason is comfort. Without a diagonal, viewing objects high in the sky through a refractor requires you to crouch or kneel in an awkward position. The SV188's 90-degree angle lets you observe comfortably while seated, leading to steadier views and longer, more enjoyable sessions.

    Will the SVBONY SV188 work with my Newtonian telescope?

    No, the SV188 is not suitable for Newtonian reflectors. Newtonian telescopes have a very specific focal plane and require a secondary mirror, not a diagonal, to direct light to the side-mounted focuser. Adding this diagonal would prevent the telescope from achieving focus.

    How will the SV188 diagonal affect views of the Moon in my 80mm refractor?

    The SV188 will provide bright, sharp views of the Moon. Its 90% reflectivity ensures minimal light loss, keeping lunar features like crater walls and rilles high in contrast. Because it's a mirror diagonal, it won't introduce any chromatic aberration (color fringing), preserving the true color and fine detail along the terminator.

    Does the SVBONY SV188 provide a "correct" image for terrestrial viewing?

    No. Like all standard astronomical mirror diagonals, the SV188 provides an image that is correct up-and-down but is reversed left-to-right. This is perfectly acceptable for astronomy, but for terrestrial viewing (like bird watching), you would need a 45-degree correct-image erecting prism.

    Can I use the SVBONY SV188 on a Maksutov-Cassegrain like a Celestron NexStar 4SE?

    Yes, absolutely. Maksutov-Cassegrain and Schmidt-Cassegrain telescopes function like refractors in that they have a rear-mounted focuser. The SV188 is perfectly compatible and is a common accessory for these types of telescopes to achieve a more comfortable viewing position.

    What is the advantage of the SV188 mirror diagonal over a basic prism diagonal?

    The SV188's main advantages are typically better light transmission and color fidelity. Its 90% reflectivity mirror surface avoids the potential light absorption and scattering of a lower-quality prism and does not introduce the slight chromatic aberration that can occur as light passes through the glass of a prism.

  • Eyepiece Connection 1.25"
    Telescope Connection 1.25" (or 2" with optional adapter)
    Eyepiece Clamp Single screw
    Reflectivity 90%
    Housing Material Metal
    Compatible Telescope Types Refractors, Schmidt-Cassegrains, Maksutov-Cassegrains
    Incompatible Telescope Types Newtonian Reflectors

    • SV188 1.25" Zenith Mirror Diagonal

      × 1

    • Dust Cap (Eyepiece Side)

      × 1

    • Dust Cap (Telescope Side)

      × 1

  • SVBONY 1-Year Warranty