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Altair 100mm 90° Giant Observation Binoculars with 18mm UF eyepieces

Altair 100mm 90° Giant Observation Binoculars with 18mm UF eyepieces
Altair 100mm 90° Giant Observation Binoculars Altair 100mm 90° Giant Observation Binoculars Altair 100mm 90° Giant Observation Binoculars Altair 100mm 90° Giant Observation Binoculars Altair 100mm 90° Giant Observation Binoculars How to remove the tripod foot/base Altair Astro 100mm Giant Observation Binoculars
Incl. VAT 20.00 % ( £233.17 )
Product Code
Altair Astro
This 2-element binocular offers huge light grasp and extremely high contrast thanks to an achromatic air-gap doublet lens design.
The colour correction is so good they have been described as semi-APO, even though they do not contain ED glass. 
For astronomy, high power nature viewing, or coastal observation, we cannot find a better price/performance ratio 100mm binocular. The difference in light grasp compared to 70 or 80mm binoculars is immediately visible, as is the higher resolution. In fact, these lenses outperform most spotting scopes and achromatic doublet telescopes of similar aperture. 

Imagine the light gathering power of two 4" refractors - one for each eye! Use your favourite 1.25" astro eyepieces for lunar and deepsky observation or even light pollution filters, which isn't possible with normal binoculars.

The included 18mm Ultra-flat eyepieces give a 65° field of view, and the overall brightness of the images is quite surprising compared with using binoviewers in a 100mm telescope with the same aperture, because each eye get's 100% of the light from 100mm aperture objective lens.

The 1.25" self-centering eyepiece holder focal position allows most eyepieces to come to focus including Altair Astro, Tele Vue Delos, Nagler, Panoptic, and the Docter 12.5 mm UWA. Of course you can also use standard 1.25" astronomy filters on the eyepieces to enhance viewing even more.

Every binocular has collimation checked before shipping.

Mounting the binoculars:

For terrestrial use and casual astronomical use we recommend a large video and or camera tripod. We recommend the Altair Sabre mount with vixen clamps and Heavy Duty L-Bracket for more serious or extended observation especially at higher powers. The ultimated solution would be the iOptron AZ PRO mount. Our optional single-arm binocular mount is also available. (Code: BINOMOUNT1).

Main features:
  • Very bright image and large field of view, well suited for observation of bright deepsky objects.
  • Independent helical focusers with self-centering compression eypiece holders.
  • Enables use of 1.25" Light Pollution filters, such as the Altair Premium 1.25" CLS filters.
  • Extra large 28mm prisms with top quality broadband multi-coatings on all optical surfaces.
  • High quality independently focusing 1.25" eyepiece holders - compression-fit with self centring brass inserts. 
  • Tough, light magnesium alloy casing.
  • Includes a carry handle with sight.
  • Extensible dew shields. Dew shield ID thread: M 116 x 1-6H, 6 mm depth.
  • Includes front dustcaps and rear dust plugs. Both eyepieces have dust caps.
  • The base has a standard 3/8" Photo tripod thread and 1/4" Photo tripod adapter so you can use your giant binoculars with a standard tripod. An additional pair of in-line threaded holes allow mounting on a Vixen-format dovetail bar, or the new Single-Arm Binocular mount (code: BINOMOUNT1).

Included in delivery:

  • 100mm binoculars with carry handle and tripod adapter
  • 4 Dust Caps
  • Set 18mm UF 65 degrees = 30 x magnification
  • Double Carton Packing, rigid foam insert.

Technical specifications: 

  • Dimensions 550 X 270 X 200mm
  • Weight 7.1kg
  • Interpupillary distance 54-75mm
  • Eyepiece Adapter: 31,7 mm / 1.25" Astro eyepiece compatible
  • Dewshield Dia. 116mm
  • Focal Length 550mm
  • Objective Lens Diameter 100mm
  • Objective angle of view: max. 2.8 Degree
  • 100mm F5.5 Proprietary CDGM dual element objective lens with improved colour correction.
  • 28mm Oversized K9 Prism Clear Aperture (field stop diameter: 25 mm).
  • Prism glass type: K9 equivalent to BAK4.
  • Broadband Hardcoat Multi-layer coatings on all surfaces.
  • Photo tripod thread: 1/4-20 and 3/8"

Performance with included 18mm Ultraflat Eyepieces:

  • Minimum Focusing Distance 25m
  • Eyepiece Lens Structure(#Elements/# Groups) 8/5 Ultra-flat design
  • Eyepiece Focal Length 18.45mm
  • Magnification with 18mm Eyepieces 30x
  • Real Field of View 65-66° Apparent Field of View 2.2°
  • Field of View at 1000m = 38.4m
  • Exit Pupil φ3.3mm
  • Relative Brightness 10.9
  • Twilight Factor 54.8
  • Eye Relief 20mm
  • Eyepiece Weight 200g
  • Eyepieces Waterproof: Yes

Staff comments - a mini-review from Nick, who has been "playing" with a pair of giant binoculars for a while now: "Imagine having two rich-field 100mm refractors - one for each eye (that's a 50% gain on bino-viewers), and that's what you're getting. Color correction is very good, in fact, other vendors describe these very well corrected Achromats as "Semi-APO". They deliver a very sharp image of the moon, star clusters and even sunspots are very dark (with twin solar filters!). The moon is great too, appearing 3 dimensional with lots of suface detail visible. Saturns rings can easily be seen at 30x with the included 18mm Ultraflat eyepieces. I tried a pair of Altair 1.25" CLS Light Pollution filters (which screw in to the eyepiece barrels like any standard 1.25" filter), and the extra light grasp gained by using two eyes gives a marked improvement on nebulae, even on the outskirts of Norwich city. The Orion Nebula takes on a 3-dimensional appearance for example, and the difference using both eyes compared to a 4" refractor is immediate. Taking them to the Norfolk coast was very enjoyable. I could see every droplet of water on a seal's whiskers right out in the sea at Winterton beach. The wind turbines and ships passing by showed plenty of detail. It's like having two telescopes side-by-side, one for each eye. The oversize 28mm prisms deliver a bright even field, giving deepsky objects some "pop". The included high quality 18mm wide angle flat field eyepieces yield 30x magnification which is just the right size for an exit pupil with or without glasses, and the field is very flat and sharp, right out to 97% (the edge being 100%). Even small lunar craters stay in focus right to the field-edge. Bottom line, no other giant binoculars I've tried in this class will give this edge of field performance and these are a big step up from say 70 or 80mm aperture. I mounted mine using the L-Bracket and an Altair Sabre mount which gave a nice smooth slewing experience. They will easily fit on the iOptron AZ PRO (with L-Bracket) for a top quality observing experience. Nick, Altair."

Altair Astro reserves the right to change the price and/or specification without notice.

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Incl. VAT 20.00 % ( £41.67 )
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