The model is equipped with a thermal insulation coefficient of R-Value 2, measured according to ASTM F3340-18. This value indicates the degree of protection against ground cold—the higher the R-Value, the greater the effectiveness in minimizing heat loss.
R-Value classification as applied in the outdoor sector:
- 1.0-2.0 – designed for summer use (recommended for nights when temperatures are above approximately 10 deg. C),
- 2.1-3.5 – suited to spring, summer, and autumn expeditions (from around 0 deg. C up to 10 deg. C),
- 3.6-5.0 – intended for cold conditions, near 0 deg. C and negative temperatures down to about -5 deg. C / -10 deg. C,
- 5.1-7.0 – optimal for winter operations, where temperatures dip below 0 deg. C,
- above 7.0 – recommended for harsh winter environments requiring maximum insulation.
Actual thermal comfort is determined by several factors, including the sleeping system (bag and apparel), ground characteristics, and the user’s individual cold tolerance.
Militaria.pl is a premium dealer of Sky Watcher.
Sky-Watcher is a brand created in 1999 by Synta Technology Corporation from Taiwan, which is now the largest manufacturer of amateur astronomical equipment in the world. Its product range includes telescopes from simple models for beginners to advanced designs such as ED refractors, Esprit astrographs, and Maksutov systems. Dobsonian telescopes are extremely popular, including the iconic models with a mirror diameter of up to 16 inches, as well as the professional EQ8 equatorial mounts valued by astrophotographers. Since 2008, the company has been developing innovative Flex Tube Dobsonian telescopes with an extendable tube, which have become a distinctive symbol of Sky-Watcher in the world of astronomy.
| Weight | 18 kg |
|---|---|
| Objective lens diameter (mm) | 120 |
| Telescope type | Refractor |
| Focal length | 1000 mm |
| Lens speed (f/x) | f/8,3 |
| Maximum magnification | 240x |
| Practical magnification range | 17-240 x |
| Telescope mount | Parallactic EQ |
| Finderscope in the set | Yes, optical |
| Limiting magnitude (magnitudo) | 12,7 mag |
| Replacement glasses in the set | Yes |
| Tripod material | Steel |
| Tube length | 1040 mm |
| EAN | 5901691622098 |
| Manufacturer code | SW-2209 |
| Brand | Sky Watcher |
| EAN |