Celestron SkyMaster 25x100 Porro Prism Binoculars — The largest conventional model in this group, combining 25× magnification with 100mm objectives, individual eyepiece focusing and an integrated tripod adapter rod for dedicated astronomical and long-range viewing.
Giant 100mm Astronomy Binoculars
The twin 100mm objectives provide the greatest light gathering in this batch for star fields, clusters, nebulae, the Moon and long-range daylight subjects. A 3° field and 25× magnification favour careful, supported observation rather than casual handheld scanning.
Optical Design and Focusing
BaK-4 prisms and multi-coated optics help preserve transmission and contrast. Each eyepiece focuses independently, a design well suited to astronomical and long-distance subjects that do not require frequent refocusing.
The published field of view is 3°, equivalent to 52m at 1,000m. Close focus is 24.4m (80ft), so this model is intended primarily for medium- to long-distance subjects.
Tripod Use and Weather Protection
The integrated sliding tripod adapter rod helps balance the 3.969kg binocular. A strong tripod and head with adequate payload capacity are essential for practical use and are sold separately.
Weather protection: Water resistant. It is not nitrogen filled and should not be treated as fully waterproof.
What Is Included?
- SkyMaster 25x100 binoculars
- Integrated sliding tripod adapter rod
- Objective lens caps
- Eyepiece rainguard
- Neck strap
- Deluxe padded carrying case
- Lens-cleaning cloth
- Five-language SkyMaster instruction manual
Please note: A tripod, solar filters and any item not listed above are not stated as included.
Specifications
Optics
| Optical design | Porro prism binocular |
|---|---|
| Magnification | 25× |
| Objective diameter | 100mm |
| Objective focal length | 417.32mm |
| Angular field of view | 3° |
| Linear field of view | 52m at 1,000m |
| Exit pupil | 4mm |
| Eye relief | 15mm |
| Close focus | 24.4m (80ft) |
| Interpupillary distance | 56–72mm |
| Dioptre adjustment | ±5 |
| Focusing system | Individual focus for each eyepiece |
| Optical coatings | Multi-coated |
| Prism glass | BaK-4 |
| Twilight factor | 50 |
| Relative brightness | 16 |
| Limiting stellar magnitude | 12.50 ideal; 11.50 moderate; 10.50 poor conditions |
Construction and Size
| Weather resistance | Water resistant |
|---|---|
| Nitrogen filled | No |
| Tripod mounting | Integrated tripod adapter rod; heavy-duty tripod sold separately |
| Carrying case | Deluxe padded carrying case |
| Dimensions | 256 × 130 × 388mm (10.1 × 5.1 × 15.3 inches) |
| Binocular weight | 3.969kg (140oz) |
Solar Safety
Warning: Never look at or near the Sun through these binoculars.
These are not solar binoculars and do not include certified solar filters. Direct or nearby views of the Sun can cause immediate and permanent eye injury.
Do not attempt solar projection and do not attach improvised or eyepiece-mounted filters.
Instruction Manual
The official Celestron documentation is provided in English, French, German, Italian and Spanish.