Barlow Tele Vue 2x with a 2-inch (50.8 mm) slip-on mount, featuring two multi-coated elements and a brass clamping ring. Includes a 1.25-inch adapter; particularly well-suited for Newtonian telescopes.
CHF 308.00incl. Swiss VAT
Part Number BWC-2211
The Tele Vue Big Barlow 2x increases the effective focal length of your telescope. Using the same eyepiece, it allows you to achieve a nominal magnification that is twice as high. This solution complements a selection of eyepieces for exploring lunar details, observing the planets, or zooming in on a specific target. The manufacturer’s part number for this model is BWC-2211.
The Tele Vue design uses two high-index glass elements and multi-layer coatings. The manufacturer tests its Barlow lenses across the entire field of view using an open system at f/4. This design is intended to preserve contrast and minimize aberrations introduced into the optical path. The final image quality also depends on the telescope, its focus, and atmospheric conditions: higher magnification does not reveal additional details when turbulence obscures them.
The Big Barlow is compatible with both 2-inch and 1.25-inch eyepieces thanks to the included adapter. The brass clamping rings hold the accessories in place without the screw pressing directly against their threads. It features a 48 mm filter thread and a captive locking screw.
Important point to consider before purchasing: Tele Vue highly recommends it for Newtonian telescopes, where it is designed to maintain focus with both eyepiece sizes. The manufacturer does not recommend using it with a 2-inch offset mirror: its length prevents parfocality, and some telescopes may not be able to focus properly. Be sure to check the mounting and travel of your eyepiece holder.
| Manufacturer | Tele Vue |
|---|---|
| Reference | BWC-2211 |
| Rated amplification | 2x |
| Flow on the telescope side | 2 inches (50.8 mm) |
| Accepted eyepieces | 2 inches and 1.25 inches with the included adapter |
| Optics | 2 high-index glass elements |
| Treatments | Multilayer |
| Tightening | Brass ring; captive screw |
| Filter thread | 48 mm |
| Approximate weight | About 340 g (0.75 lb, according to the manufacturer) |
What magnification will I get? Magnification is calculated by dividing the telescope’s focal length by that of the eyepiece, then applying the nominal factor of 2x. Choose a combination that is suitable for your instrument’s diameter and provides a stable image.
Is this a Powermate? No. This is a two-element Tele Vue Barlow lens, distinct from the Powermate line. For a photographic setup or an unusual spacing, the actual magnification may depend on the distance between the Barlow lens and the image plane: do not consider the nominal magnification to be a guarantee for every setup.
