CCDs are incredible devices, gobbling photons that have travelled the vastness of space with great efficiency. Their Achilles heel is to also accept spurious signals from the immediate vicinity — within their own traitorous circuitry. Steve Ringwood investigates a CCD cooling chamber that will reduce a camera’s noise and increase its efficiency for both daytime and nocturnal imaging.
Reviewer Steve Ringwood waxes lyrical about this benevolent telescopic accessory — a new high-power 5x Barlow lens designed for 1.25-inch (31.7mm) eyepieces. It delivers a fairly ambitious amplification factor of five times to any ocular used with it, but its four-element design ensures that it does this whilst retaining image fidelity.
Use this combination solar diagonal and blocking filter with a conventional refractor of 100mm aperture or less and you have an instant calcium K-line solar instrument, writes reviewer Steve Ringwood. With it you can see super-granulation on the Sun’s surface and other features outside the reach of hydrogen-alpha telescopes — all in complete safety.
Reviewer Steve Ringwood acknowledges that some stunning astrophotography is possible by use of a camera and its terrestrial lens alone. But in dim nocturnal light, it can be difficult to accurately aim the camera at a particular target in the sky. The Geoptik SLR hotshoe finderscope adapter is a convenient mediator between a DSLR camera and a Synta-style red dot or optical finder’s dovetail for precise pointing.
While a vast body of space imagery lies just an internet click away, nothing compares to seeing an astronomical object in the eyepiece. But it is only natural that one should wish to capture such views with a camera. Steve Ringwood investigates Celestron’s ingenious Ultima Duo hybrid eyepieces intended to combine your visual and photographic needs in one package.
In developing the beautifully minimalist Dobsonian, the resourceful John Dobson quite rightly earned himself a kind of immortality, telescope-wise. Yet even after the decades of development and tweaking that have occurred since, the concept continues to evolve today. Steve Ringwood casts his expert eye over a new line of Dobsonians from Explore Scientific.
Steve Ringwood takes a good look through Vixen’s SLV range of eyepieces, offered in ten focal lengths from 2.5mm to 25mm. Each is designed to offer exceptional clarity and contrast across a 45°—50° field by employing rare earth Lanthanum glass. He also notes that each eyepiece’s polygonal rubber grip acts as an ‘anti-roll’ feature, hopefully protecting them from a fall!
Microscopists enjoyed the advantages of binocular vision long before someone thought to apply this principle to telescopes. Using both eyes, the brain is able to interpolate both fields, resulting in a gain in contrast and a consequently improved perception of detail. Steve Ringwood appraises a very stylish model from Venonscope aimed at the top end of the twin eyepiece market.
© 2019 Pole Star Publications Limited