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Old 14-10-2008, 01:46 PM
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BerrieK
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Join Date: Feb 2008
Location: Orange
Posts: 650
The Hyperion have 20mm eye relief and a reported 68 deg FOV (largest useful FOV to the human eye when it is stationary). As Jimmy says you can use as 1.25" or 2" , but speaking from experience they are best used in the 2" focuser, otherwise you may find that you need to use a focal extender.