William Optics 50mm f/4 Guide Scope with 1.25" RotoLock - Blue # M-G50WBII

Our Price: $128.00
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In Stock (1 Available)
Ships by Next Business Day
Our Product ID: OFIN-WO-M-G50WBII
Manufacturer SKU: M-G50WBII
Item Can Ship: Worldwide
William Optics 50mm f/4 Guide Scope with 1.25" RotoLock - Blue # M-G50WBII

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Product Details

Important Note: This guider has only 6.2mm of back-focus available. Hence, it can only be used with 1.25" cylinder-type or "Mini" cameras from QHY, ZWO, SBIG, etc. Please check your camera or autoguider's back-focus requirements to ensure compatibility before you purchase this.

All new, unique, fully multi coated WO 50mm f/4 guiding scope with 1.25" RotoLock adapter that fits perfectly on your William Optics telescope. This item requires that your guiding camera should have a 1.25" nosepiece.

Please note that this item cannot be used as a finder with a reticle eyepiece; it does not have sufficient back-focus (in-focus) travel for that application.


  • High-quality 50mm f/4 achromatic objective
  • 1.25" RotoLock camera holder
  • Rotolock adapter rides on an M48 threaded barrel, allowing it to be screwed in or out to obtain 8mm of focus travel. Lock ring included.
  • White powder painted with blue trim
  • Perfectly suited for William Optics or other refractors


  • Tube outside diameter = 54.5mm (2.15")
  • Dewshield outside diameter = 58.2mm (2.29")
  • Minimum length = 253mm (9.96")
  • Maximum length = 261mm (10.28")
  • Rotolock focus travel = 8mm (0.31")
  • Weight = 460g (16.2oz)
  • Finder bracket sold separately