Skip to content
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.
Baader Glasspath Corrector for Maxbright Bino and Mark V
Baader Glasspath Corrector for Maxbright Bino and Mark V
Baader Glasspath Corrector for Maxbright Bino and Mark V
Baader Glasspath Corrector for Maxbright Bino and Mark V
Baader Glasspath Corrector for Maxbright Bino and Mark V
Baader Glasspath Corrector for Maxbright Bino and Mark V

Baader Glasspath Corrector for Maxbright Bino and Mark V

by Baader Planetarium
SKU BAA-2456314
$144.00 - $155.00
$144.00
$144.00 - $155.00
$144.00
Price Match Policy!
  • Corrects for insufficient back focus to allow binoviewer use
  • Available in 1.25x, 1.7x, and 2.6x magnification factors
  • Removes prism-induced chromatic and spherical aberrations
  • Attaches via Baader/Zeiss ring dovetail or standard T-2 threads
  • Enables multiple magnifications with a single pair of eyepieces
1 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Baader Glasspath Corrector for Maxbright & Mark V Binoviewers

    The Baader Glasspath Corrector is the essential component for using a binoviewer with telescopes that lack sufficient back focus, offering corrective factors of 1.25x, 1.7x, or 2.6x to push the focal plane outwards. This multi-coated lens system simultaneously eliminates color errors introduced by the binoviewer's prisms, sharpening the view in fast optical systems. Its dual mounting system, featuring a Zeiss dovetail and a T-2 (M42x0.75) thread, ensures seamless integration with Baader Maxbright and Mark V binoviewers.

    Achieving Focus in Any Telescope with 1.25x, 1.7x, and 2.6x Correction

    The primary function of a Glasspath Corrector (GPC) is to solve the most common barrier to binoviewing: insufficient focuser in-travel. By extending the telescope's focal length, the GPC moves the focus point significantly outward, allowing you to achieve a sharp image where it was previously impossible. The three available factors—1.25x, 1.7x, and 2.6x—allow you to select the precise amount of correction your specific telescope requires.

    A Schmidt-Cassegrain might only need the 1.25x corrector, while a Newtonian reflector with very limited back focus will likely require the 1.7x or 2.6x model. This system also acts as a high-quality Barlow lens, effectively tripling the number of magnifications you can achieve with your existing eyepiece pairs.

    Eliminating Prism-Induced Chromatic Aberration

    Beyond its mechanical function, the Baader GPC provides a critical optical correction. The long path of light through a binoviewer's internal prisms can induce noticeable chromatic aberration (false color) and spherical aberration, especially in telescopes with focal ratios of f/6 or faster. This softens planetary detail and adds distracting color fringing around bright objects like the lunar limb.

    The Glasspath Corrector's specialized lens design counteracts these errors, restoring the high-contrast, color-pure image delivered by your telescope's main objective. The result is a significantly sharper, more satisfying two-eyed view of the Moon, planets, and double stars.

    Dual T-2 and Zeiss Dovetail Mounting for Baader Binoviewers

    Designed for total system compatibility, the GPC features two mounting methods. It can be screwed directly into the Zeiss ring dovetail found on the Baader Mark V and MaxBright II binoviewers for a secure, direct connection. It also includes a T-2 (M42x0.75) clamping flange, allowing it to be inserted anywhere in a T-2 threaded accessory train.

    • Positional Flexibility: Placing the corrector in front of a T-2 star diagonal, rather than between the diagonal and the binoviewer, can reduce the required optical path by an additional 15mm.
    • Reconfigurable Optics: The lens elements can be removed from their cell and reversed to optimize performance between different binoviewer models, ensuring the convex lens surface always faces the telescope objective.
    • Broad Compatibility: The GPC is engineered to attach directly to Baader T-2 diagonals and various 1.25" or 2" nosepieces, creating a rigid and versatile imaging train.

  • Which Baader Glasspath Corrector factor do I need?

    The choice depends entirely on your telescope's available back focus. 1.25x is for scopes with only a small focus deficit, like many refractors and SCTs. 1.7x is a versatile mid-range option for many reflectors. 2.6x provides the most correction and is typically required for Newtonian reflectors that have very little back focus to spare.

    Does the Glasspath Corrector work with the Baader Mark V binoviewer?

    Yes. All three correctors are compatible. The 1.25x and 1.7x models may require the internal lens cell to be unscrewed and flipped for optimal correction with the Mark V, while the 2.6x model works natively. The corrector attaches directly to the Mark V's Zeiss ring dovetail.

    Where should I install the Baader Glasspath Corrector for the best results?

    For the greatest reduction in required back focus, the corrector should be placed as far forward in the optical train as possible. Installing it on the front of your T-2 star diagonal, before the light path is bent 90 degrees, can save approximately 15mm of back focus compared to installing it between the diagonal and the binoviewer.

    My 8" f/10 SCT can't reach focus with a MaxBright II binoviewer. Which corrector should I get?

    For most Schmidt-Cassegrain telescopes, which typically have generous back focus, the 1.25x Glasspath Corrector is the ideal starting point. It provides enough outward focus travel to solve the problem without increasing magnification unnecessarily, preserving a wider field of view.

    I see color fringing on Jupiter with my f/5 Newtonian and a binoviewer. Will a Glasspath Corrector help?

    Absolutely. This is the second key function of the corrector. The color fringing you see is chromatic aberration introduced by the binoviewer's prisms, which is exaggerated in a "fast" f/5 optical system. The Glasspath Corrector's optics are designed to cancel this specific error, resulting in a much sharper, color-pure image of the planet.

    Can I use the Glasspath Corrector for anything besides a binoviewer?

    Yes. Because it uses the standard T-2 thread, you can use a Glasspath Corrector to solve focus issues with other accessories. For example, it can be used to bring a DSLR camera to focus on a telescope that would otherwise not have enough in-travel.

  • Magnification Factors 1.25x, 1.7x, or 2.6x
    Primary Function Extends focal point to achieve focus with binoviewers
    Secondary Function Corrects for prism-induced chromatic and spherical aberration
    Binoviewer Threads Baader / Zeiss M34 Ring Dovetail
    Accessory Threads T-2 (M42x0.75)
    Compatibility MaxBright, MaxBright II, and Mark V Binoviewers
    Net weight (kg) 0.02
    Optical Design Glaspath Corrector
    Compatible telescopes Refractors, Schmidt-Cassegrain, Newton
    Optical length (mm) ≥ -30 (1:1.25)
    -65 (1:1.7)
    -120 (1:2.6)

    • Baader Glasspath Corrector

      × 1 (Selected Magnification)

  • Baader Planetarium Warranty