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Old 30-06-2011, 09:04 AM
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wasyoungonce (Brendan)
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wasyoungonce is offline
 
Join Date: Jul 2006
Location: Mexico city (Melb), Australia
Posts: 2,336
Hi Bill.

I previously looked up the TV site and found the correct spacing which is 56+/-2mm. I even called TV USA on the phone to confirm this.

I also have the TV spacer kit TLS-2245 which has various spaces from 1mm, 2mm to 25mm and have tried combinations of these, photographically, unsuccessfully. I went so far as to make a hybrid T ring that was 1.5mm shorter focal path length and this didn't work as well.

I found the optimum spacing with the least star elongation was at the published spec distance. However, my stars are not pinpoint at this and are worse at any other spacing distance. At this optimum spacing they are not grossly elongated at the edges, in fact they are probably better than the native focal length edge stars.

I purchased this unit as others had reported that the other major FL reducers like WO etc did not work with the triplet. The Astrotech type II and Hotech field flatteners apparently work very well but I was after a reducer flattener.

I got to say...at F6 the image FOV is ..to coin a phrase "most excellent" and enticing.

I'll still use the reducer but crop out the offensive areas which kind of negates the usefulness of the reducer.
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