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Hi Mark,
I'm out of Australia at the moment so I don't have the TEC flattener manual. I think you can download it from Yuri's site. You will need to get parts from AstroPhysics to make the flattener work. The explanation in the manual and at AP can be a little vague. But, basically you remove the end cap of the FT focuser (the 2" clamp thingy) and the flattener screws directly onto the FT focuser. Then you need to get the part from AP the fits the bayonette on the camera end of the flattener. To that you need a tube of the proper length to give you the 85mm total distance to the chip. That is the bayonette fitting plus the extension tube length is added to the back focus distance of the CCD to the end of whatever camera fittings you have. Now there is a complication because you should also probably calculate how the BF length is changed by the filter thicknesses or any other lens in that path. I cannot give you the formula from memory but it confuses most everyone!! In any case it might mean that the actual distance you should shoot for is 87 mm or so. I'm just guessing here so that is not anything else other than a guess. I think I remember Yuri saying that anywhere between 84-86 mm is close enough. And, yes, you can just focus with that arrangement and be done. And you should have a very flat field and great stars
Speaking of which, what motorized focuser are you getting for the FT? My microtouch system has worked very very well. If you want to manually focus as well you might look at the Optec solution. Both are quite good for sure.
Peter
PS I saw your posting on the TEC user group as well. I have to say that I concur with a couple of the posts about your camerta choice. Personally I think you might regret going with a lower resolution. I've imaged from Sydney (KAF8300 ccd) with a 2x barlow in the system (around .6 arc-sec) to good effect. If you look at my pbase pages the photos of M83 and M16 were both done this way. So, if what you want is wide field/nebula shots, no close ups of galaxies, then sure your solution is OK.
Last edited by PRejto; 18-08-2014 at 12:48 AM.
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