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.
Skywatcher N 305/1500 telescope:
This telescope provides a huge aperture for detailed DSO observing. It is one of the largest Newtonian telescopes produced by Skywatcher and collects about 40% more light than a 254mm telescope. This means that not only bright high-contrast planetary observing is possible, but that the telescope has its forte above all in observing DSOs. Whereas most small telescopes are only capable of showing the cores of some galaxies, this telescope can clearly show the spiral structure. Globular clusters can also be observed as fascinating objects in this giant, and some can be resolved into countless individual stars over the entire field of view.
The telescope has a diffraction limited, parabolic primary mirror which is centre-marked for assisting precise adjustment of the optics. The thin spider vanes and small secondary mirror mean excellent contrast. The high resolution available can reveal an extremely high level of planetary detail with sufficiently good seeing. Although the telescope is one of the largest that can be placed on an equatorial mount, this telescope is still easily transportable. For the exact weight, please refer to the technical data. The solid 2-inch Crayford focuser provides enough support for even very heavy eyepieces and cameras. The fine focusing makes it easy to find the optimum point of focus. The f4.9 aperture ratio makes it virtually predestined for astrophotography, allowing this extremely powerful telescope to be used for short exposure times with a generously wide field of view. The use of an optional coma corrector will provide photos that are sharp right up to the edge of image.
The advantages in a nutshell:
- enormous light gathering power from 304mm aperture
- thin secondary mirror spider vanes and small secondary mirror ensure high contrast image
- very ‘fast’ optics make it excellent for astrophotography
- diffraction limited, parabolic primary mirror
Included in delivery:
- tube ring clamps with prism rail for rapid mounting of OTA
- 9×50 finder scope
- 2″ Crayford focuser
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.
