Markfan

Hi guys, Thank you all for your worthwhile contributions. I liked the idea with the ribbon cable and using the spider as a heat sink. In the past I discovered some ultra thin very rigid metals and as long as the spider vanes are straight, it can have the depth to support the weight. I was thinking of an electronic solution in regards to the focusing, perhaps a conversion of an existing electronic non slip focuser. One question, is there any difference in the optical setup between a setup with secondary mirror and one without? Normally no corrector is needed, when attaching a CCD with an eyepiece to a focuser in a standard Newton telescope with a secondary mirror, why can I not use the same setup but skip the secondary flat mirror. I am catching the focused beam of the primary just in the same way and at the same point, only the focused beam does not get folded 90 degrees. I would understand if one would say "the use of a correcter or flattener enhances both setups", but why does it always come into play with the one mirror setup? Thank you, Markus

Hi Peter, the footprint of my CCD is smaller then my secondary, the cabling I would have tried to integrate in the spider vanes, basically constructing new cabling unless the cabling would be out of focus if exiting the telescope a distance ahead of the spider. The CCD is cooled to -40 degrees but I do not know what would happen outside the camera regarding temperature effects, this might be a project killer. My main question is regarding the field flattener/corrector setup, if it would be needed. I have seen field flattener/correctors that would do the job online. In regards to mounting the CCD and Barlow/eye piece projectin train I am not too worried, I have build very stable spiders in the past. regs, Markus

Hi, I want to place a CCD camera where the secondary mirror is, remove the sec. mirror completely. It,s a home made F5 14 inch. Do I have to use a coma corrector or/and a field flattener? Can I use a Barlow with a field flattener or coma corrector, can I use eye piece projection with a field flattener or coma corrector? Many thanks, Markus