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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
ZWO 30mm f/5 APO Guide Scope
ZWO 30mm f/5 APO Guide Scope
ZWO 30mm f/5 APO Guide Scope

ZWO 30mm f/5 APO Guide Scope

by ZWO
SKU ZWO-30F5
$149.00 - $149.00
$149.00
$149.00 - $149.00
$149.00
Price Match Policy!
  • 30mm Aperture
  • 150mm Focal Length (f/5.0)
  • Triplet Apochromatic (APO) Lens Design
  • Precise Helical Focuser
  • Lightweight at 0.77 lb.
2 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • ZWO 30mm f/5 APO Guide Scope

    The ZWO 30mm f/5 APO Guide Scope integrates a 150mm focal length with a triplet apochromatic lens design into a compact package weighing just 0.77 lb. Its 30mm f/5.0 optical system is engineered to produce sharp, color-free guide stars, providing the high-precision data needed for accurate tracking with imaging telescopes.

    Triplet APO Optics at 150mm Focal Length

    Unlike standard achromatic guide scopes, this scope's triplet lens design corrects for chromatic aberration, rendering guide stars as tight, focused points of light without color fringing. This optical correction allows autoguiding software to calculate a more accurate centroid, which translates directly to tighter, rounder stars in your final image. The 150mm focal length provides enough image scale to effectively guide primary imaging telescopes up to 750mm in focal length.

    Precise Helical Focuser at Just 0.77 lb.

    Achieving and maintaining sharp focus on your guide star is non-negotiable for accurate guiding. This scope features a non-rotating helical focuser with a locking screw, allowing you to make fine adjustments and then secure the focus position against accidental bumps or temperature shifts. The entire optical tube assembly weighs only 0.77 lb., adding minimal load to your mount and making it easy to balance your entire imaging rig.

    • Direct Threaded Connection: The rear of the focuser includes M42x0.75 T-threads, allowing you to securely attach any ZWO ASI camera for a rigid, flex-free connection.
    • 1.25" Compatibility: For cameras with a 1.25" nosepiece, a standard compression ring holder provides a secure grip without marring the barrel.
    • Synta-Style Mounting: The included dovetail bar fits standard finder shoes on most telescopes, making it a simple drop-in replacement or addition to your setup.

    ZWO 30mm f/5 APO vs. the Original 30mm f/4

    While the original ZWO 30mm f/4 guide scope is a capable and compact option, the f/5 APO model is a significant optical upgrade. The primary differences lie in the optical design and focal length, which directly impact guiding accuracy with longer telescopes.

    • Optical Design: The older f/4 model uses an achromatic doublet design, which can exhibit minor color fringing on bright stars. The f/5 APO uses a triplet lens system to virtually eliminate this, producing sharper stars for more precise centroid calculations.
    • Focal Length: The f/5 APO's longer 150mm focal length provides a more detailed view of guide stars compared to the 120mm of the f/4 model. This increased image scale allows for more accurate guiding corrections, especially when paired with longer focal length imaging scopes.

  • What is the main advantage of the ZWO 30mm f/5 APO over the older f/4 model?

    The primary advantage is the triplet apochromatic (APO) optical design. This provides significantly better color correction, resulting in sharper guide stars. Sharper stars allow your guiding software to make more precise calculations, leading to better tracking accuracy and rounder stars in your long exposures.

    What is the maximum focal length I can effectively guide with the ZWO 30mm f/5 scope?

    A common rule of thumb is that your guide scope's focal length should be at least 1/5th that of your imaging telescope. With its 150mm focal length, the ZWO 30mm f/5 is an excellent match for imaging telescopes up to approximately 750mm in focal length, making it ideal for wide-field refractors and smaller Newtonian reflectors.

    Can I use the ZWO 30mm f/5 guide scope for visual observing or as a finder?

    Yes. While designed for autoguiding, its high-quality triplet optics make it a superb finderscope. When paired with a 1.25" eyepiece (sold separately), the 30mm aperture and 150mm focal length provide a bright, wide field of view for locating objects. It essentially functions as a premium, straight-through finder.

    How do I attach my ZWO ASI120MM Mini guide camera to the 30mm f/5 scope?

    The ZWO ASI120MM Mini and other ZWO cameras with 1.25" bodies are designed for this scope. You simply insert the camera's 1.25" barrel into the back of the guide scope and secure it with the thumbscrews. For a threaded connection, you can unthread the 1.25" holder to reveal the M42x0.75 threads underneath.

    How well will this 30mm f/5 guide a Celestron EdgeHD 800 at f/10?

    An 8" EdgeHD has a focal length of 2032mm. The 150mm focal length of this guide scope is shorter than ideal for such a long imaging focal length. While it can work, for optimal results with an SCT, an Off-Axis Guider (OAG) or a guide scope with a longer focal length (e.g., 250mm or more) is generally recommended to better match the image scale.

    Is the ZWO 30mm f/5 a good match for a RedCat 51 imaging setup?

    Absolutely. The RedCat 51 has a focal length of 250mm. The 150mm focal length of the ZWO 30mm f/5 is an excellent match, easily providing the resolution needed for precise guiding. Its low 0.77 lb. weight is also a perfect fit for the lightweight RedCat, ensuring the entire system remains easy to balance on a portable mount.

  • SKU Number ZWO-30F5
    Aperture 30mm
    Focal Length 150mm
    Focal Ratio f/5.0
    Lens Design Triplet
    Weight 0.77 lb.
    Length 6 in.

    • ZWO 30mm f/5 Mini Guide Scope

      × 1

    • Synta-Style Dovetail

      × 1

    • M4x8 Screws

      × 2

    • M3x6 Screw

      × 1

  • ZWO 2-Year Warranty