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Old 15-05-2007, 10:37 PM
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freespace
Resident Eccentric

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Join Date: Apr 2007
Location: Sydney
Posts: 159
Quote:
Originally Posted by 74tuc View Post
Hi Steve,

1. Barlows have many uses and magnification ranges but I only use them to get the next eyepiece focal length in the range. I really do not know why manufacturers choose x2 as this will duplicate a given eyepiece(eg. 12mm to 6mm, 50mm to 25mm etc.) the best multiplication factor to give one the smoothest eyepiece focal length range is a factor of (twelfth root of 2) 1.23 something. The closest "Barlow" to this that I know about is the Tak x1.6 five element extender.
Same here. I can easily reach my scope's maximum of 200X (102mm refractor) with a barlow and my 5mm. Its just I want something between 100 and 200, and with my current collection of eye pieces I need a 3x, so I was hoping for some "cheap thrills".

Attempting to acquire a 6.4mm meade, to give 154X with a barlow.

Cheers,
Steve
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