190304 - Sky-Watcher Star Adventurer
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EQUIPMENT: camera=Nikon D90 (stk) optics=NIKKOR 70-300 DX kit zoom, f/4-5.6 filter=(none) mount=Sky-Watcher Star Adventurer - Pro (1st model released) guiding=(none) |
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As learning progresses in the hobby of amateur AP, so does the equipment used. The physical constraint of a fixed tripod mount quickly teaches that the only images possible are generally limited to appx 50mm focal length or less, and no longer in exposure than appx 20s. Those constraints limit one to capturing only "wide-field" images of the Milky Way and whole constellation starscapes. Trying to press "deeper" beyond those limits into the details of the night sky results in "star trails", an effect that is very undesirable for AP. In fact, photographers go to very great lengths to mitigate the effect.
Once one gains a respectable command over the functionality of a DSLR camera, the next logical step to improve the quality of images is to obtain equipment which will enable tracking of the apparent movement of the sky. Beyond a simple fixed tripod, the addition of this capability opens-up a whole new realm of AP by way of increased exposure times, longer focal lengths, stacking of multiple images and improvement in processing skills.
The Sky-Watcher Star Adventurer (also known as a "tracker" in common astrophotography vernacular) is a motorized camera mount capable of compensating for the sky's apparent movement caused by the rotation of the Earth. The SWSA tracker moves in only one axis - being that of right ascension ("RA"); but, it works very well. In recent years Sky-Watcher has advanced the SWSA to newer models with new features. There are now at least two (2) other manufacturer's that have brought competing trackers to the market.
A tracker allows one to use a full array of camera lenses, all the way up to the largest typically owned by many amateur photographers (in the range of 300±mm focal length). It also enables one to capture longer exposures (up to 180s = 3m). Within the realm of longer focal lengths, a tracker also allows one to take multiple exposures and digitally "stack" them on a computer to improve signal-to-noise ratios and image contrast, and reduce the electronic noise inherent in digital photographs. Some very popular targets that a tracker brings within reach include M42 the Orion Nebula, M31 the Andromeda Galaxy, and M13 the Great Globular Star Cluster of Hercules.
Once one gains a respectable command over the functionality of a DSLR camera, the next logical step to improve the quality of images is to obtain equipment which will enable tracking of the apparent movement of the sky. Beyond a simple fixed tripod, the addition of this capability opens-up a whole new realm of AP by way of increased exposure times, longer focal lengths, stacking of multiple images and improvement in processing skills.
The Sky-Watcher Star Adventurer (also known as a "tracker" in common astrophotography vernacular) is a motorized camera mount capable of compensating for the sky's apparent movement caused by the rotation of the Earth. The SWSA tracker moves in only one axis - being that of right ascension ("RA"); but, it works very well. In recent years Sky-Watcher has advanced the SWSA to newer models with new features. There are now at least two (2) other manufacturer's that have brought competing trackers to the market.
A tracker allows one to use a full array of camera lenses, all the way up to the largest typically owned by many amateur photographers (in the range of 300±mm focal length). It also enables one to capture longer exposures (up to 180s = 3m). Within the realm of longer focal lengths, a tracker also allows one to take multiple exposures and digitally "stack" them on a computer to improve signal-to-noise ratios and image contrast, and reduce the electronic noise inherent in digital photographs. Some very popular targets that a tracker brings within reach include M42 the Orion Nebula, M31 the Andromeda Galaxy, and M13 the Great Globular Star Cluster of Hercules.