Opticstar TeleXtenders increase the effective focal length of the optics that it is used in conjunction
with, thus producing higher magnifications in imaging and visual applications. They are similar to barlow
lenses in concept, but they have the distinct advantage that they maintain a consistent magnification
irrespective of their placement in the optical train. This quality enables the optics designer to optimise
the optics for maximum performance.
When using a barlow to increase the magnification of your optical system, the results will be dependent
on where the barlow is placed in the optical train. If for example, you place a x2 barlow lens in front
of the mirror diagonal instead of behind it (barlow-diagonal-eyepiece as opposed to diagonal-barlow-eyepiece),
the results will differ. You won't get 2 times magnification in both set-ups. The magnification varies
with placement. However, with the Opticstar TeleXtenders, even if the distance is changed, the magnification
always remains the same. You can place your TeleXtender anywhere along the optical train between an eyepiece
or a camera, and if you are supposed to get 2 times magnification (with a x2 TeleXtender for example),
you will actually get 2 times magnification.
This is particularly important in imaging because you may want to introduce an accessory like a flip mirror
or filter wheel in between the TeleXtender and a CCD camera, which would increase the distance to the focused
image. This difference in design allows for consistent results whether increasing the magnification of a lower
power eyepiece for visual observation or using the Opticstar TeleXtenders in imaging applications. Visual
observers also benefit because the magnification can be increased without sacrificing on eye relief.
Better Eye Relief
The TeleXtenders add flexibility to your accessory line-up. They allow the increase the magnification of any
eyepiece with the same barrel size that you already own. In other words, 2 eyepieces offer 4 magnification
choices with the addition of a TeleXtender. Typically, lower magnification eyepieces have better eye relief
than higher power eyepieces. With a TeleXtender it is possible to increase the magnification and still
maintain the generous eye relief of the lower power eyepieces. This is especially important for eyeglass
wearers or for those with fast telescopes who can really use high magnification eyepieces to their limit.
Better Manufacturing Standards
The Opticstar TeleXtenders are optimized through each design, fabrication, and testing process. The superior
quality large optical elements produce high contrast and high resolution images.
Fully multi-coated with EMD enhanced optical coatings result in durable coatings, bright and sharp images.
All 4 optical elements have blackened edges to reduce internal reflections and increase contrast.
The insert barrel of each extender is double-tapered to allow smooth insertion to, and removal from,
a telescope's eyepiece holder, focuser or diagonal, however the wide dimension of the taper helps prevent
the TeleXtender from falling out of the telescope should the set-screw holding it in place become loose.
Opticstar TeleXtenders deliver research-quality images backed by a solid design, careful fabrication,
multiple tests, and continued diligence to deliver a cutting edge, quality product.