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New Swarovski BTX Ocular Module

February, 2018

by Michael and Diane Porter

BTXSwarovski's new BTX Ocular Module, a new option for their ATX spotting scopes, makes for a visual experience that goes beyond anything we've seen before. Imagine looking through a superb spotting scope, but using both eyes!

When you first look through the BTX eyepiece module, you feel as if a door has opened wide. It's really hard to convey the expansive sense of immersion and presence.

Your brain is designed to compare images coming from two eyes and use the information coming from both to construct what you see. With two channels coming into your visual processing center, you perceive more detail. Using two eyes makes the image more real, richer, and more natural.

It's also more comfortable to view with two eyes. You can gaze for a long time. Any sense of squinting through one eye or sense of eye fatigue is gone. This is wonderful for extended observation of the behavior of birds or other animals.

This BTX accessory is one of the options made possible when Swarovski created their innovative ATX scope design that grouped the prism system and the eyepiece together as one part, and the objective front lens as another. This allowed them to make the system more modular. You can use the same eyepiece with a 65, 85, or 95mm objective.

BTXIn this ATX system, the two parts of the scope have a large point of connection, a rock-solid bayonet mount, like the lens on an SLR camera. This makes a very sturdy, solid scope and allows the strongest, most stable way to connect an SLR camera for digiscoping. (And they make a special APO connector for most of the common SLR cameras.)

It also allows you to replace the eyepiece module on any of the ATX models with something like the BTX module as easy as changing lenses on an SLR camera.

Other features of the BTX

Forehead rest
Swarovski has also designed in a forehead rest. You can turn a dial and adjust its position. This even further increases the comfort of long-term viewing. The forehead mount is removable.

Swarovski has thoughtfully addressed the ability to quickly point your scope at a bird by adding a sighting device. It lets you quickly point the scope so that, when you look through the scope, the bird is going to be in your field of view.

Interpupillary distance adjustment
You can move the two eyepieces closer together or farther apart, to fit your eyes precisely.

Eyecups adjustment
The eyecups twist in and out to accommodate your eyeglasses status.

The BTX features Swarovision Field Flattener and high definition lenses, which give great edge-to-edge clarity, eliminate distortion, and bring out high color contrast.


The BTX doesn’t zoom: its magnification is fixed. But Swarovski also makes a 1.7x Magnification Extender if you need more.

95 mm Objective Module + BTX = 35x
85 mm Objective Module + BTX = 30x
65 mm Objective Module + BTX = 30x

ME1.7xMagnification Extender

The Swarovski ME 1.7x Magnification Extender increases the magnification by a factor of 1.7.

95 mm Objective Module + ME1.7x + BTX = 60x
85 mm Objective Module + ME1.7x + BTX = 50x
65 mm Objective Module + ME1.7x + BTX = 50x

The ME 1.7x Magnification Extender also works with the regular ATX Ocular Module instead of the BTX.

95 mm Objective Module + ME1.7x + ATX  = 51x - 119x
85 mm Objective Module + ME1.7x + ATX  = 42x - 102x
65 mm Objective Module + ME1.7x + ATX  = 42x - 102x

Specifications of the BTX with different Objective Modules

  BTX by itself with 95 mm ATX with 85 mm ATX with 65 mm ATX
Magnification   35x 30x 30x
Field of view @ 1000 yds.   96 ft. 112 ft. 112 ft.
Minimum focus distance   16.4 ft. 12.5 ft. 7.2 ft.
Eye relief 21 mm 21 mm 21 mm 21 mm
Interpupillary distance 57 - 71 mm 57 - 71 mm 57 - 71 mm 57 - 71 mm
Length 6.9 in. 18 in. 15.9 in. 14.6 in.
Weight 50 oz. 97.3 oz. 88.8 oz. 77.3 oz.
Owner's manual click click click click
Swarovski warranty click click click click


Please call us toll free 800-779-7256 for advice on choosing binoculars or other birding products.

2197 236th Blvd.
Fairfield, IA 52556

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