Περιγραφή
Skywatcher offers a wide range of Newtonian telescopes under the Explorer label. The telescopes are available individually or in combination with a variety of mounts.
BD as in “black diamond”: the Explorer BD series of telescopes are very popular with amateur astronomers because they offer high-quality parabolic optics at a very reasonable price. Many amateur astronomers started with an Explorer BD, and many have remained true to their Newtonian to this day.
The Explorer PDS offer the same mirror optics, but are optimised for astrophotography: a more favourable focal position, thinner secondary mirror support and a focuser with gear reduction for focus adjustment.
N 150/750 telescope: This versatile Newtonian reflecting telescope provides both beginners and more experienced amateur astronomers plenty of light and high stability for a very modest price. It collects so much light with its generous 150mm diameter that distant DSOs such as the Ring Nebula in Lyra or the Dumbbell Nebula become beautifully visible and globular clusters, such as M13, resolve into a multitude of individual stars at their edges. Planetary observing provides rich detail in images of Saturn, Jupiter, Venus and Mars. The f5 focal ratio means this reflector falls into the class of ‘fast’ Newtonian telescopes. This telescope is therefore particularly suitable for astrophotography. The light gathering capacity of the 150 is 460 times greater than that of the naked eye alone (with a 7mm fully dilated pupil).
The advantages in a nutshell:
- relatively high light gathering power thanks to 150mm aperture
- resistant to vibration and wind due to compact design
- diffraction limited parabolic primary mirror
- high-contrast image due to thin secondary mirror spider vanes
- portable and quickly assembled
- exposure times for astrophotography can due to the short focal length
The PDS version of the Explorer comes with a dual speed focuser. This has a 1:10 reduction ratio for sensitive focusing which is most important for astrophotography, but is also very useful for visual observing. The tube length has been slightly shortened compared to the Explorer P version and the secondary mirror has consequently been enlarged in order to further optimize the system for astrophotography.
