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Re: [Sextants] Plath Sextant: Advice - Required.
From: Kieran Kelly
Date: 2004 Jan 19, 08:53 +1100
From: Kieran Kelly
Date: 2004 Jan 19, 08:53 +1100
Joel Jacobs wrote: "I thought someone had noted a sextant ........with a binocular attached..... Unless a binocular or telescope is internally stabilized, any power above 7 would make it useless for taking sights because as power increases it accentuates the movement of the body. Furthermore, the ability of the lens system to transmit light decreases as power increase as does the field-of-view. So that the higher powered scopes today are primarily used for sun sights by experienced navigators who still practice the art of CELNAV. Better prismatic high powered scopes do work for shooting early rising planets and the moon, but not for stars. Lecky is correct in condemning the process." The sextant in question is a Plath about 1920 with a set of binoculars - a form of accessory telescope. They are very low power, I would say no more then 2x-4x. No internal stabilisation. Field of view is no problem and they are easy to hold steady. Plenty of light into the optics. Kieran Kelly Sydney Australia
