Skip to content

UPS Shipping Delays / COVID-19 Response Statement

Apertura 6" f/4 Imaging Newtonian OTA - 6F4N

shipping truck Free shipping

Apertura 6" f/4 Imaging Newtonian OTA

A great introductory telescope for wide-field imaging, this fast 6" f/4 Newtonian optical tube assembly has diffraction-limited optics and an extended tube in front of the focuser that serves as a built-in dew/light shield. The sturdy 2" Crayford focuser has linear bearings that result in a rigid draw tube and virtually no flexure. A 35mm extension tube is included just in case you need to extend focus. You can easily attach a 35mm DSLR camera, webcam, or CCD/CMOS imaging camera and be confident in the mechanical build of the Apertura 6" f/4 Newtonian.

The 7" diameter optical tube is 22.5" long and is made of rolled steel instead of aluminum, adding to the rigidity of the telescope as a whole. A center-spotted parabolic primary mirror housed in an aluminum cell fitted with six "push/pull" collimation knobs that is guaranteed to be diffraction limited makes easy, no-tool collimation possible. The optical tube assembly is painted white, and will look great on any mount you choose. The OTA length forward from the focuser has been extended to increase contrast by keeping stray light from hitting the secondary mirror.

A pair of felt-lined split tube rings and an 8.75" long Vixen-style dovetail mounting plate are included with the OTA. The 6" Imaging Newtonian can be attached to a wide variety of equatorial mounts by either using the Vixen-sized dovetail that is included or adding your own Losmandy-style dovetail plate to the rings. The Apertura 6" OTA also has a quick-release finder adapter attached, and accepts the included 50mm finderscope bracket. An 8x50 straight-through optical finderscope slides easily into this bracket.

The Apertura 6" f/4 Reflector OTA's linear focuser, as mentioned above, is different from standard Crayford focusers found on most reflectors. There is less wear on the focuser draw-tube, less flexure, and more rigidity due to design differences that support the drive rail and draw-tube along the length of travel instead of at a few contact points. This 2" linear bearing focuser also sports dual-speed 1:10 focus, a tension lock knob, and a focus lock knob so that your focus point stays put while imaging. The draw tube has 2" of travel, and has a focusing scale marked on the top to help you come back to the same focus point again and again. A 2" to 1.25" compression ring adapter is included as standard equipment.

This Product Comes with the Apertura Absolute Warranty!

  • Two-Year Warranty against product defects.
  • Three-Year Accident Replacement Program that begins after your initial 2 year warranty expires.
  • Your Apertura Absolute Warranty is transferable.

Download a copy of the Apertura Absolute Warranty for more information on this program, how to make a claim, and why it is important to keep your original receipt and the product's original boxes & packaging!