How did our modern picture of the universe come into being? Helge Kragh’s book tells this fascinating story in an unusual format that blends factual and fictional elements. The ‘interviewees’ are a collection of eminent twentieth century cosmologists, among them Einstein, Eddington, De Sitter, Hoyle, Arrhenius, Dirac and Schwarzschild. Reviewed by Ian Welland.
Piers Bizony’s book gives the reader an insight into the twenty-first century’s new era of human spaceflight with Virgin Galactic, SpaceX and more vying with traditional space agencies and emerging space-faring nations such as China. Reviewer Kulvinder Singh Chadha says that Bizony successfully captures what is happening right now in this generously-sized book with lush images aplenty.
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.
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