(6 customer reviews)


In stock.

Astronomy Magazine 2022 Star ProductOur newest and largest XL Series Binocular Telescope features 5″ apochromatic (FCD100 / FK-61 triplet) objectives, with a relatively-short 650mm focal length, and 27mm of clear prism aperture. The BT-127XL-SD was designed to be the highest-performing production binocular on the market, without regard to cost. Even with two 5″ triplet objectives and massive prisms, magnesium-alloy construction makes it remarkably-lightweight at just 24.5 lbs. With its unmatched image quality, we think it’s a much more practical alternative to the world’s largest 150mm binoculars, which are very heavy, very expensive, and difficult to mount. Finished in iridescent “Luna Pearl” White with gold-anodized trim, it’s also quite attractive.
The BT-127-XL-SD includes our premium 14mm (46x) 70° AFOV eyepieces. 30x (22mm) and 93x (7mm) are also available. The included heavy-duty case has wheels on one side for easy transport.
Every BT-127XL-SD is tested and tuned to perfection prior to shipping, with collimation certified to 163x. 3-year Limited Warranty.

Mounting Options:
Recommended tripods are the Oberwerk TR3 hardwood tripod or the Manfrotto 161MK2B, which has a crank-up elevator. Either tripod can be configured with the Oberwerk XL-280 Fork Mount or Manfrotto 612 NitroTech Head.
Fully-automated “go-to” operation is available using the iOptron HAZ31. BT-127XL-SD YouTube review.

XL Series Accessories

Additional information

Weight 65 lbs
Dimensions 35 × 22 × 18 in
Focal Length



2.35° (30x)

Exit Pupil

5.3mm (30x)

Eye Relief

15.0mm usable (46x)

Minimum Focus

25 meters

IPD Range


Product Weight

24.5 lbs.

6 reviews for BT-127XL-SD

  1. Nicolas Bechwati (verified owner)

    I purchased previously the BT-100 and it was a great design quality workmanship,
    I am so excited and can’t wait to get the new BT 127 model

  2. Howard Doll

    My BT 127’s arrived safely and well packaged. I want to thank you folks for the T shirt and ball cap as well.

    I have been using these binos for weeks. I have enjoyed them each time I get behind the eyepieces. I wanted to do a review after my trip to Moab, UT. The skies were better than where I live in AZ. I could not ask for better skies the nights I have been in Moab.

    The last few weeks were playing around with different eyepieces for my 127’s. I found I am very comfortable at 27 to 52x. To me this is where these binos performed. Once one obtains the eyepieces they are comfortable with – the possibilities with these binos are endless!

    The glass is everything I wanted in a BT. I was so blown away by the wonderful sights I saw. Again (as I say a lot) everything was in my face. Some of the examples of many picked objects were:

    M104 – the dust lane could be made out as well as the core.

    M65/66 – these were like looking at smaller versions of M31.

    M81/82 – both were beautiful at 52x. M81 looking like m31 (again),
    and M82 had that dust split in the middle.

    M13 – WOW! Talk about the mottling of the outer stars, and a
    beautiful center. So impressive at both 27 and 52x.

    Carbon stars like T Cancri, and X Cancri were drop dead gorgeous
    with their blood red color.

    Double stars like Albereo, Cor Caroli, and Castor are sharp and tru to color.

    These were just a few examples of how well these binoculars perform. I am constantly looking further into deep sky all the time with them. Again the possibilities are endless with these BT’s.

    I have my 127’s perched up on the Oberwerk fork mount, which may weigh more than a fluid head, but I am comfortable using fork mounts. It does require a bayonet adapter if one is considering using a 161MK2B tripod. This set up is unbeatable with an astro chair to make it complete.

    The case these binoculars come in, is solid in structure. The wheels make toting the binoculars very easy.

    Overall, the 127 BT is a stellar performer, and is a keeper with me. It is solid construction and does have an attractive finish. These binoculars are for the serious hobby astronomer who demands performance and portability of a giant binocular.

    Thanks again Kevin for making this possible. These binoculars are definitely the flagship of my astro arsenal.

  3. ROBERT D. (verified owner)

    I am very pleased with my purchase of the BT-127XL-SD, the clarity of this Binocular telescope, is amazing, I also purchased the 22mm eyepieces and the MANFROTTO 612 NITROTECH Head, and could not have been happier with it! The quality of the product and customer service are great, I also own the BT-100-45 which I have had for six years, and still love it, but wanted to upgrade to the SD Series, which is a bit lighter to travel with, and is awesome. You cannot go wrong with either of these binoculars, I definitely recommend, and will continue to be a customer of Oberwerk. They make Excellent quality binoculars, and customer service is outstanding.

    Thank you.
    Robert D.

  4. Daniel Barth

    Finally got the 127’s outdoors for a test today!

    It’s about 15F this morning, so I was out for about 45 minutes before the cold drove me back inside. You can see the binos set up on my front porch and the view across the valley. FYI, that ridge across the valley is about 2 miles away (3.25 km).

    Good News:
    1. Setup is EASY. Less than 3 minutes from opening the case to ready to view. Manfrotto tripod is rock solid and the snap lock head makes mounting these monsters a piece of cake.

    2. Balancing is just as easy, and the captive rail system (can’t slip off!) sets my mind at ease while I make adjustments. Resetting the balance point when I switch eyepieces is so easy, I don’t hesitate to find the most precise balance point which improves the action of the fluid head. Once everything is locked, it is very secure – no worries!

    3. Motion of the Nitrotech head is so smooth, I had little trouble tracking turkey vultures in flight! Able to see individual feathers on the wing tips from 2 km away, color was spectacular!

    4. No detectable CA. Looking at snowy scenes, sparkles off ice crystals, bright snow clinging to dark branches – no sign of color fringing. To be fair, there was so much heat coming up from the ground, I limited myself to 50x max (13mm EP) and I was happier at 32x (18mm EP – both 68* wide).

    None so far. Very happy with my purchase! It’s supposed to be clear tonight, but temps down in single digits…. I’ll see if that works for me!

    If you have been considering these magnificent binoculars and hesitating because you are concerned about difficulties with transporting and mounting them, put your fears to rest and jump in – absolutely worth it!

  5. Yves Jacques Deetjen

    Yves Jacques Deetjen (Verified Owner) December 26, 2022

    Clearly, the Oberwerk BT-127XL-SD binocular telescope is an ideal visual instrument for the avid amateur astronomer who is seeking the ultimate best. For years I have been contemplating on purchasing a binocular telescope to complete my arsenal, I finally have found the answer. I purchased the BT-127XL-SD and I am absolutely thrilled with its performance. This BT binocular telescope series was especially created to meet high expectations, and at the same time symbolizes the manufacturer’s commitment to high standards. The binocular reaches unparalleled image brightness and contrast thanks to the (FCD100) / (FK-61) triplet objective lenses which render a three dimensional visual effect that can not be ignored. I congratulate Kevin Busarow, the founder of the company who has gone beyond the realm of normal expectations in order to satisfy the requirements of the fastidious enthusiast. Now I can proudly say that I own a very well conceived instrument with such elegant design. I particularly appreciate the painstaking attention to ergonomic detail resulting in a beautifully contoured binocular telescope. Its iridescent ” Lunar Pearl ” white finish with silver anodized trim makes it appropriate for my living room view. It is indeed an effective and a conversational piece one can cherish for a very long time.

    By: Yves Jacques Deetjen

  6. Rick Evans

    I purchased the BT-127XL SD with the suggested Manfrotto tripod and HAZ31 GOTO mount head. This is as close to perfection as I think it is possible to get in a binocular telescope rig. I continue to use my BT-82XL ED on a regular basis as well and both are excellent instruments.

    Because I’m in Bortle 6 skies, I’ve taken to using both BTs with nightvision monoculars and this makes objects and details visible that otherwise would require a telescope of very large aperture. When using regular eyepieces with Oberwerk BTs I would recommend not using eyepieces that have any barrel undercuts or slopes and to stick with straight 1.25 barrels because these work best with the eyepiece locking rings.

    Should you ever want to re-collimate your BTs for use at higher than normal magnifications or because your eyes have unique characteristics, this is easily accomplished by rotating one of the objectives and it is simple to do yourself without needing to send the unit back for re-collimation. Kevin at Oberwerk can explain the process. For the BT-127 I had a simple tool crafted for this purpose, a sort of elementary spanner to help in rotating the outer locking ring. But for use in the normal magnification range most people are accustomed to, you will likely not need to re-collimate as the binoculars are factory collimated for this magnification range and hold collimation very well.

    I recommend getting a red dot finder (sold by Oberwerk) and buying a height adjustable observing stool or chair. I have seen debate about whether a 90 degree or a 45 degree eyepiece angle on a BT is more desirable and in my opinion the 45 degree angle Oberwerk BTs provide is just fine. I would also recommend buying the optional battery pack to run the HAZ31 mount head to avoid cord entanglement issues. In conclusion, I would like to emphasize that this is really a premier binocular telescope setup and I doubt anyone could purchase anything significantly better (within reason).

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