BBC Sky at Night Magazine
Orion Monster Parallelogram mount & 25x100 binoculars kit
A well-balanced and versatile observing system that delivers deep-sky results
Well-mounted large aperture binoculars are a joy to use, especially for the larger deep-sky objects, so Orion’s new binocular and parallelogram combo piqued our interest. The GiantView 25x100 binoculars, which come in an aluminium case, have a Porro-prism individual-eyepiece focusing design that is covered with a thin rubber armour. There is a longitudinal bar that connects the hinge to cuffs on the objective cells. This bar increases the rigidity of the binoculars and carries a sliding mounting post that enables you to achieve perfect balance when you mount them. But, at the point of perfect balance, it obstructs the minimum achievable interpupillary distance (IPD) – the distance between the pupils of your eyes – to 66mm.
When we looked down the objective tubes, we saw that the prisms are secured in proper cages, not merely clipped to the housing, so they should not become dislodged by minor bumps. The entrance to the prism housing does not restrict the light path, so that light from the full 100mm aperture is transmitted to the eyepiece. This examination also revealed that the insides of the objective tubes are smooth and without light baffles, although they are stepped where the objective tubes join with the objective cells and delete prism housings. This means that stray light is not well controlled, to the extent that it is intrusive when, for
example, a first quarter Moon is within about 5° of the
target area of sky. We didn’t notice this stray light from any stars, but it must cause some reduction in contrast.
Enjoying the sights
We thoroughly enjoyed our first stargazing outing – as
we put the binoculars and mount to the test – and targeted the constellation of Orion, the Hunter. The
Orion Nebula, M42, was bright, with a structure that
seemed to increase in detail the longer we examined it.
The Trapezium Cluster was cleanly split as we moved it over the central third of the field of view. We found the
colour rendition was very good with recently dimmed
Betelgeuse looking ruddy. We also tried some galaxies in Ursa Major: the Whirpool, M51, revealed both of its core structures, and the Pinwheel, M101, was easy to see despite its low altitude. Open clusters, however, are the real strength of these mounted binoculars. While the Pleiades, M45, was as stunning as we expected, we spent a long time enjoying the Messier clusters in Auriga and Gemini and had to drag ourselves away from the Milky Way’s Cassiopeia region.
Given the weight of these binoculars, this enjoyment was only made possible by Orion’s Monster Parallelogram mount. It has some nice touches, one of which is the facility to vertically adjust the mounting bracket in order to achieve perfect balance: you won’t
find any positions in which the binoculars refuse to stay
put without you over-tightening the mount’s joints. This
makes it easy to achieve that ‘floating binocular’ effect
that is the hallmark of a good parallelogram mount. The helpful instructions are detailed and well-illustrated.
The tripod is a Synta-made model with 1.75-inch diameter legs, and a north pin (initially for equatorial mounts) which is used to prevent the parallelogram from unscrewing itself. The mount arms measure 57cm between fulcrums, giving a vertical range of 75cm, making it easy to share views with people of various heights. There is some vibration when you change target, but this dies down in seconds. There are two counterweights and you can experiment with their positions to achieve a short vibration-damping time.
When the binoculars are pointed vertically with the tripod extended, the eyepiece height is a maximum of 148cm. Orion suggests purchasing an extension pier for the mount, but you can use a garden recliner, as lying back makes high-altitude observing more comfortable.
This is a complete observing system that will suit anyone who wants a reasonably priced step-up to big mounted binoculars, using a mount that can take other astronomical instruments and which has the versatility to make it ideal for sharing the night sky with others.