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Something amiss with my FS-102?

Started by ivanong, 02/11/2003 05:31AM
Posted 02/11/2003 05:31AM Opening Post
Hi All: Recently I purchased a FS-102 new (after an 8 year astronomical hiatus) and I am not sure if there is something wrong with the optics. Using a different selection of eyepieces (University Optics 5mm, Early 90's Celestron 30mm Plossel, 90's Televue WF 26mm), the focus seems not to "snap" in place confidently, instead there seems to be a very tiny range of ambiguity where I am wondering if I have reached focus. I find myself toggling in and out the focuser and repositioning my eye. At one end of the range, the stars are very sharp but laser-thin elongated. On the other end, they can be "spikey". Looking at Jupiter, I detect a blue fringe on half the circumfrence and a red fringe on the other side. Looking at Sirus, the out of focus image appears a little oval. I don't seem to remember this feeling of being a little worried about the optics 10 years ago when I bought a Vixen 4" fluorite. I remember a more "snap into place" kind of focus. Anyone with an opinion as to how I can proceed to diagnose the problem? Can my new Televue Everbrite star diagonal be out of collimation and be causing this problem?
Thanks, Ivan
Posted 02/11/2003 10:05PM #1
Try star testing the scope without your diagonal although I doubt this is problem. Perhaps it is out of collimation -if I was you (since the scope is new) I would send it to TNR to be looked at.