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01588 620717
PENTAFLEX POWER TANK NEW!
Rechargeable
Mobile Multi function Power Station
This rechargeable 12v battery pack has been designed principally for use with motor-driven astronomic telescopes. It obviates the need for regular battery purchase and ensures a plentiful, consistent supply of power. In addition, the red light feature is particularly apposite since it allows astronomers to see their telescope, star maps, books, accessories etc at night without destroying any hard won dark adaptation*. The unit also sports a large white light reflector for more conventional use ie telescope break down at the end of an observing session.
*The retina in your eye features two types of cell; cones and rods. In simple terms, the cones are utilised under normal light conditions whilst the rods come to life in low light, or dark, conditions. In ordinary light the rods become “bleached” as the pigment (rhodopsin) they contain is destroyed and they cease to function. However, in the dark, this bleaching process is reversed as the rods slowly regenerate the lost rhodopsin and the retina recovers its sensitivity. The key word in this description is “slowly;” it can take 45 - 60 minutes for the eyes of a given individual to become fully dark adapted. This process can be monitored by simply looking into the night sky and noting how the number of visible stars increases dramatically over the adaptation period. Understandably, astronomers in the field go to some lengths to avoid ordinary, white light since the briefest exposure to it (a torch, security light, car headlights etc) utterly destroys night vision and puts them right back at the start of the dark adaptation process
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Specification |
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Mobile Rechargeable Power Station, will Power All Goto Telescopes
Protective Fuse |
Launch Offer!
Was - £49.95
NOW ONLY - £39.95
All major credit cards accepted - please phone our hotline Tel: 01588 620717
Evergreen Optics
The Cann Barn, Mellington, Church Stoke, Montgomery, SY15 6TQ
Tel: 01588 620717