The Tele Vue 3X Barlow - 1.25-Inch size is a 2-element achromatic Barlow system.
If you don't compromise optical quality when it comes to your telescope's eyepieces, why should you compromise with a barlow lens? Thanks to Tele Vue's innovative 2-element design, now you can get superb sharpness that matches the performance of Tele Vue eyepieces. The Televue 3X Barlow (#TE-BLW-3125) is an achromatic system, but the design gives better color correction over its competitors at the edge of field. Optically corrected down to f/4 for use with fast f/ratio reflectors, the 3X Barlow is parfocal with Tele Vue Plossls under 32 mm, and provides excellent performance with any scope type.
The Televue 3X Barlow - 1.25-inch is fully multi-coated, with blackened lens edges and internal anti-reflection threading for excellent contrast. Its 3.75-inch length allows this Barlow to be used in star diagonals and what's more, the barrel is threaded for standard 1.25-inch filters. As a unique feature, the 3X Barlow has a safety groove. Have you ever dropped a thumbscrew in the dark? No more. It has a captive thumbscrew which helps hold it in place should the focuser thumbscrew accidentally loosen!
Because the Tele Vue 3X Barlow - 1.25-inch measures 5-inches in length, it is marginal for use with star diagonals. With physically long eyepieces, this doesn't create an optical problem, but be aware an inexpensive diagonal may not keep the combination secure. The weight of a large eyepiece and this barlow can cause the diagonal housing to become loosened in the visual back and allow it to shift or turn without warning. Proper prior knowledge can avoid these problems.
As Al Nagler says: "Tele Vue's Barlows were envisioned as magnification windows. Multi-coated high-index glasses assure optimum aberration correction, exceptional contrast, and virtually no light loss. Tele Vue Barlows achieve their design goals even when tested by the fastest scopes. They even improve our competitor's eyepieces and telescopes!"
Tele Vue 3X Barlow - 1.25-inch Features
- Internal safety groove and captive thumbscrews!
- Blackened lens edges and internal anti-reflection threading.
- Parfocal for most Tele Vue Plossl eyepieces.
- Five year Tele Vue warranty.
OPT Part Number: TE-BLW-3125