Steve Ringwood casts his expert eye over and into a 2-inch push-fit dielectric mirror diagonal for refractors and catadioptrics from Explore Scientific. This star diagonal delivers optical fidelity since it has a mirror that has been honed to 1/12th wave and reflects 99 percent of incoming light to the eyepiece.
Red dot finders have been around for some time now, adopting various guises in their ongoing improvements. Yet with this new version from Celestron, there is definitely a new slant on their design. Nested binary rings quite literally target an object as its own bullseye, effectively keeping an object in view to enable perfect alignment, says reviewer Steve Ringwood.
Steve Ringwood reviews a pair of waterproof, nitrogen-filled 70mm aperture binoculars designed for medium-to-long-range terrestrial and astronomical observations. The Helios Stellar-II range is available in 10.5x and 15x magnifications and boasts 85 percent light transmission — all in a shockproof magnesium alloy body weighing just 1.75kg.
We can become very attached (even fondly) to the instruments that give us such a thrill observing the Universe. It can come very hard, then, for us to question their quality. Reviewer Steve Ringwood takes a look through a Ronchi eyepiece that permits the user to obtain a definitive and exacting exposure of a telescope’s optical quality.
Reviewer Steve Ringwood takes a look through the Bresser Messier AR-152L/1200 — a classic achromatic doublet refractor of 152mm (six-inch) aperture and f/8 focal ratio. Available as an optical tube only with mounting rings, dovetail, carry handle, 8×50 finder, 26mm eyepiece, diagonal and T-adapter, the instrument employs Bresser’s bespoke Hex Focus system.
Thirsting for the stars, novices in astronomy are often seeking a one-stop telescope solution to quench these initial desires. It is generally advised that this preliminary instrumental step be made with an able and economical all-rounder. Reviewer Steve Ringwood believes that this ‘scope, aimed at the beginner, hits all the right notes.
Reviewer Steve Ringwood appraises a headband flashlight that enables night vision with due respect to the needs of astronomy. White and dark-adaption red illumination is provided by one white and three red LEDs, respectively, in a 83g low-profile unit that does not protrude like some that aspire to Dalek-like proportions.
In order for a telescope to perform to theoretical limits its optical components must be perfectly aligned. With an optically fast Newtonian reflector this can be a challenge, but a laser collimator makes the task much easier. Steve Ringwood investigates Howie Glatter’s Blug™ — a charming contraction of ‘Barlowed collimation plug’.
Reviewer Steve Ringwood takes a look through a versatile 25mm eyepiece from Baader Planetarium that has a field cross-hatched by an illuminated reticule that permits measurement through sub-divided etched lines. It can also usefully employed as a guiding eyepiece as it is fitted with a T-2 thread, plus 1.25″ and 2″ nosepiece adapters are available.
ED glasses are fast becoming ubiquitous in astronomical equipment, particularly in banishing the remnants of chromatic aberration of the classic refractor. Steve Ringwood takes a look at a 115mm (4.5″) f/7 air-spaced triplet from Orion in the USA. Designed for both visual use and astrophotography, it sports a beefy three-inch dual-speed Crayford focuser and comes supplied its own hard carry case.
© 2019 Pole Star Publications Limited