Kurt, a home-made Barlow is an easy solution to customizing EFL. You can select a negative achromat to suit your needs; you might peruse the selection at Surplus Shed. Perfect achromatism isn't a concern since you are imaging at a single wavelength. On Sun, Apr 25, 2010 at 3:46 PM, Canopus56 <canopus56@yahoo.com> wrote:
Joe and Patrick -
Thanks for the comments. It turns out the 1.5x Powermate isn't made anymore. Today I did a focus test chaining a 2.5x Powermate and with a nose mounted 0.5 1 1/4" focal reducer on an eyepiece. It seemed to yield about 1.25x to 1.5x but the scope did come to a focus. I didn't have time to do a test image today. Hopefully, that will better match the camera or have a wider in-focus travel length. The test had much lower resolution than the prevailing amateur high-end standard-of-practice using the 60mm Lunt Ha and Ka scopes. http://solardatabase.free.fr/tableau.php .
At 2pm there was small prominence rising at the east-east-south limb.
- Kurt
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