Piet Le Roux

Yes the reversed Kellner or type II Kellner does have a different lens configuration as the Original Kellner or type I Kellner, as I seen it being referred to in some literature, the same literature referred to a Plössl as a type III Kellner! But I suppose we can refer to it as we see fit as long as we are talking about the same diagram, but the most used term is reversed kellner. However I have no interest in the different terms used to refer to the RKE, reversed Kellner, type II Kellner or long spaced König, but only to bring to the attention, of those who are interested, that it is a fine eyepiece when used in F10 to F15 telescopes , which I have, to observe dim doubles, nebula or galaxies and that most of the design, that are still being made, are not called RKE or reversed Kellner!

Although this is an old topic it is one that is of interest for me now. The "super"and MA or even Super MA eyepieces that I have come across and have inspected, I believe are revesed kellners because the original Kellner had a doublet eye lens and single field lens these have a doublet field lens and single eye lens. I suspect that the revesed Kellner design are propriety and for this reason they do not want to name them as such. Edmund RKE has the patent rights and made this design famous, they are still selling a 1.25" range of these which includes their famous 28mm. The Celestron E-Lux range of 2" Kellners, 26, 32 and 40mm, are also reversed Kellners but are sold as just Kellners. My interest in these started with the 40mm that I use in my 8" F10 SCT and although it has a little more distortion as my 27mm Panoptic it is notably brighter which helps when you are looking for faint galaxies with 8" SCT. I then compared a Super 10mm with my 7 and 13mm Naglers, the objects were notably brighter in the 10mm than the 7mm Nagler but about the same as my 13mm Nagler, my conclusion is simply that less glass means more light and although the Super or MA has less FOV and do scatter with bright objects, my main goal are faint galaxies and planetary nebulae. Resolution is not bad with these cheap eyepieces and I could split any double that I can split with the Naglers. I think these eyepieces has the best glass VS performance ratio.

I have a LX6 Premier drive and 2120 10" OTA and that has PPEC . When the RA is running it will beep about every 8 minutes, that's when the worm gear is at its starting point and when it has done one rotation it beeps again. If it does not beep it could be that the sensor above the worm gear shaft has come lose, when I got mine this had happen, it picks up a small magnet in the shaft. But the telescope can function without PPEC