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Meade 102ED / TV 8mm Radian

Started by dconra12, 11/27/2009 08:53PM
Posted 11/27/2009 08:53PM Opening Post
I picked up a Meade 102ED a while ago that was out of adjustment. The cell collimation was way out of whack and the screws for the radial ED element adjustment were all missing. I picked up an artificial star and went to work. The cell collimation went fine since it is the same as for my old C-8. At about 400x with the artificial star slightly far side focus I noticed what appeared to be bluish green coma cutting through the fresnal rings. I think I found what the radial screw were for! By adjusting the radial screws the bluish green coma went away, at least as near as I could tell. Not being an optician I had no idea if what I was doing was correct or not. Only a clear sky would tell me any more.

I picked up a Televue 8mm Radian a week or so ago and have been anxious to try it out because my 8mm plossel was a pain for my wife to use with glasses.

This evening we were finally able to look around a little bit with the 102ED and the 8mm radian. The moon us unbeleivable. The contrast was fantastic and I could see detail like never before. My wife described the highlights as being diamonds. Needless to say I was very happy. Crater shadows didn't show any false color on either side of focus and in focus I could find no color fringing at all. The moon was at about 45deg elevation and couldn't see any color abnormalities at all, even with some atmospheric turbulance. The next target was Jupiter. The moons looked like tiny sharp disks but the planet itself didn't fare so well. We could make out a couple of the major cloud bands and that was about it. Finally I found some color shifts. Jupiter was about 20 degrees above the horizon and upon accasion the admosphere caused the blue on side red on the other, at least now I knew my eyes hadn't gone mono on me.

The old Meade 102 and the TeleVue 8mm radian eyepiece were both performing very well. Guess I will have to sell something and pick up another radian.
Posted 11/28/2009 04:21AM #1
Before you settle on Radians I have one suggestion. There are many good deals that come up frequently on Amart for pre-owned Pentax XLs. I went through the ortho, TMB planetary, Radian progression before trying the XLs but I have now stuck with them. I find the 10.5, 7, and 5.2mm models most useful to me. Some say to avoid the 14mm but I haven't tried it yet as I use a 13mm Nagler. Others find the newer XW line better, but those eyepieces are also more expensive. Your call and enjoy. BTW, I am not trashing the Radians, they are fine eyepieces, I just like the Pentax' better.