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Hi guys,
I already have a 0.6X reducer so I don't think 0.5X would be a big enough next step. I have been using it successfully for a few years on the nosepiece of my Stellacam3 on a 6" f5 GEM mounted tracking newtonian scope, but I have recently been building a equatorial platform for my 12" f5 dob, and would like to get the benefit of wide field and low equivalent f ratio. 0.3X would be great (and about the same field as the 6" 0.6X combination but giving half the f value), but finding one is the challenge. I have no problem with focus, although with the focal reducer it needs in-focus (i.e. getting the camera + focal reducer combination closer to the primary) rather than out-focus, so I'm not sure what you mean there. My dob mount is the flextube type, so I can achieve that by not extending the secondary cage position fully.
Is there some optical limitation with 0.3X and newtonians (since 0.3X are available for SCTs), or is it just that for most newtonian configurations getting sufficient in-focus would not be possible?
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