TS-Optics 5x Premium Barlow Lens 1.25" - 4 elements, telecentric

Visual use:

This mighty 5x Barlow will easily meet the magnification demands of any telescope system. The TS High-Power 5x 4-Element Barlow Lens quintuples the power of any 1.25" telescope eyepiece, providing far more magnification than a 2x or 3x Barlow.

Optics:

Featuring a high-quality 4-element lens design, the TS High-Power 5x Barlow will render exquisite images without introducing additional chromatic abberation, while providing a monstrous 5x power boost. The Barlow lens elements are fully multi-coated with anti-reflection coatings to ensure maximum light throughput for bright, crisp views. The lenses are also edge-blackened to further maximize contrast and sharpness.

Solid Body:

The body of the TS High-Power 1.25" 5x 4-element Barlow is machined from solid aluminum with a grip-friendly rubber exterior. The 1.25" barrel is internally threaded for use with Orion 1.25" eyepiece and imaging filters. The inside of the 5x High-Power Barlow´s barrel is also glare threaded to help prevent internal reflections.

Compression ring:

A brass compression ring secures any inserted 1.25" telescope eyepiece in place without marring or scratching the barrel, keeping all eyepieces used with the 5x Barlow in like-new condition.

The advantages of a telecentric Barlow lens

In addition to the advantages of a typical Barlow lens, the telecentric design has two other advantages: First of all, the magnification factor is independent of the eyepiece distance, so you can put double polarizing filters, filter drawers and similar accessories between the lens and the eyepiece without increasing the magnification factor.

And second, the telecentric design does not extend the eye relief of the connected eyepiece. This is advantageous for the long focal length eyepieces that are often used in this context with their usually already large eye relief, as if this is too big, one can hardly hold the viewing position, which possibly leads to kidney being.