In-depth review: Swarovski Optik BTX

Today, Swarovski Optik announced its newest product - the BTX. Following the well-received ATX/STX system of modular spotting scopes, the BTX complements the product line with an angled, binocular eyepiece module to be used with the existing 65/85/95 objective modules. I had the opportunity to test the BTX during the last weeks in the field, and am happy to share my opinion with you. It's no surprise that the BTX comes with absolutely flawless optics of unbeaten quality. Hence, I will focus of aspects of ergonomics, usability and differences to the ATX system in this review.

Binocular vision

Call the BTX a hybrid between binoculars and spotting scope. Its aim is to enable scope users to benefit from human vision in its most natural, binocular way.
Long-time watching, as birders do it when scrutinizing large flocks or during seawatching, is the target use of the BTX.

Relaxed birding

Clearly, the BTX has been developed to raise comfort during long sessions of wildlife watching over long distances. The concept of watching birds at high magnification with two eyes instead of just one is simple but astonishingly convincing.

Key facts

  • two eyepieces (adjustable distance)
  • fixed magnification (30x on 65/85 and 35 on 95 objective modules)
  • forehead rest and advanced aiming aid
  • weigth including objective modules: 2195g (with 65), 2520g (85), 2760g (95)

My experiences with Swarovski Optik's new baby


The BTX comes with - obviously - two eyepieces of the same size as in EL32 binoculars. The forehead rest that helps  support the user's forehead is a curved and padded piece of plastic. The height of the forehead rest is adjustable by a wheel located on top.

The newly designed aiming aid in form of a small black tube protrudes from the housing in the top right corner. Contrary from what you might know from Swarovski Optik scopes, it's not just a hollow plastic straw, but contains some optics and a sun-shaped target.

Both forehead rest and aiming aid are part of the black rear section of the BTX and can be easily taken off for cleaning and repairing purposes.


Making it as small and lightweight as possible were surely top priorities when designing the BTX. Still, it looks rather bulky at first sight, knowing just the slim ocular end of ATX/STX scopes. But considering that it is built for two eyes, there might not be too much potential for reduction in the future.

The small eye pieces give a different yet comfortable feeling. Their distance to each other is adjustable, which is essential and logical but makes it more difficult to show what you see to someone else. Remember how easy it is to let someone else take a quick look through your scope - this becomes a bit more difficult, since people have different eye spacing.

The diopter correction is a ring located on the base of the right eye piece. Unfortunately, it’s missing a locking mechanism and was repeatedly randomly set after I took it out of my backpack.

Considering that the BTX is one half of a pair of binoculars attached to a scope, you might naturally grab it like binoculars and find the adjustment wheel of the forehead rest where you would usually find the focusing wheel (which is in fact the wide ring on the objective module).

The rather heavy BTX shifts the center of gravity of the whole combination quite far back. Regular tripod heads cannot balance this, so you will need a (video) head with very long lens plate. Swarovski Optik faces this challenge by introducing a new gimbal head, seen in the main photo above.

In the field

I tested the BTX on all three available objective modules - and the quality of watching with both eyes blew me away. For how the BTX performs on the different options, see below. I consider the 85 mm objective module the best partner for the BTX, so the following lines are based on my experiences with this combo.

Compared to the monocular versions, the BTX is heavier by about 600 g. Whatever you choose, owning a BTX will make you carry more in the field. With this in mind, I think of the BTX much less of as a walkaround piece of equipment, but a stationary device for hides, seawatching points or whenever you have a car close by.

The BTX has a fixed magnification, depending on the objective module: 30x on the 65 and 85 mm, and 35x on the 95 mm objective module. I’m not a fan of zooms (I’ve been a dedicated user of 30x wide angle eye pieces back in the pre ATX days), so I’m not missing it. If this is not the case with you, there’s a new 1,7x extender!
The BTX is quite sensitive to shake, so a very sturdy tripod/head combination is a must to get the best out of it.

Performance on different objective modules

Not only the magnification, but also the brightness of the image and depth of field change with the available objective modules. Brightness is lowest and depth of field widest on the 65 mm, intermediate on the 85 mm and the other way round on the 95 mm. While it’s clear that you want an image as bright as possible, I wasn’t aware of the significant difference the depth of field makes when watching birds. Since it's smaller on the 95, you have to focus much more (often) than with the 85. So much more, that I would clearly vote for the 85 mm objective module as the ideal partner for the BTX.


All I can say so far is that cell phones can be attached via the brand's own iphone adapter or third party products (which I use for my Samsung S5 and S6) in just the same way as they are combined with EL32 binoculars.


I consider the BTX to be a great new product that avid birders, spending lots of time watching birds, will just adore. The downsides are weight and size, so I think the BTX cannot replace a "classic" ATX scope, which is just more versatile and easier to carry/transport. If you're willing to make your watching experience more comfortable and intense and you want to spend the money - got get one, you won't be disappointed.

There's more!

Also watch out for the special new gimbal tripod head (PTH) and the balance rail (BR) that come with the BTX, as well as the 1.7x extender (ME)!
Check out Swarovski Optik's blog post on the BTX.