Help,I picked up a used Lightbridge. While examining my new scope I thought was removing the Meade eyepiece QX Wide Angle 26mm I was actually taking in apart. Suddenly in my lap I have 4 lenses of different thicknesses and 4 spacing rings. Does anyone tell me the proper sequence on how to reassemble the eyepiece? I called Meade and they were no help at all and so far google searches have come up short, thank you.
Meade Lightbridge
Started by Otis261, 04/16/2014 01:46PM
Posted 04/16/2014 01:46PM
Opening Post
Posted 04/17/2014 04:54AM
| Edited 04/17/2014 04:31PM
#1
My 20mm & 15mm QX are arranged thus (but only three spacers): from the eye end, a thin-edged plano-convex singlet with plane(flat) side towards eye, followed by a thick doublet (look for a line around the edge that indicates two lenses glued together) with it's flat or flattest side towards the eye lens, followed by another plano-convex singlet (which has a somewhat thicker edge than the eye lens) & arranged with it's curved side towards the eye end, finally a plano-concave(inward curve) singlet with it's flat side towards the field stop or telescope side. Yours should be similar, and select spacer arangment that prevent each pairing from actually touching each other (although they may be quite close on axis). IOW, try the thinnest lens placed flat side towards eye end, followed by the thickest lens with it's flat side also towards the eye end, followed by the other positive (outward-curved surface) lens placed flat side towards telescope end and lastly the negative lens (the one with an inward-curved surface on one side) placed flat side towards telescope end. The spacers prevent adjacent glass surfaces from actually touching each other (although they may be quite close on-axis) so examine closely to deduce which goes between which lenses; the correct arrangement might be a medium one between 1st pair of lenses, thickest spacer (or perhaps two spacers?) between next pairing followed by the thinnest spacer last (in front of the concave lens element). When assembled correctly, the field stop should be in sharp focus & a fingertip or other object placed within the field stop should appear sharp when properly placed. If any lens has two curved surfaces, the least-curved side should correspond to *flat* in the above directions. I can't help with the 4th spacer, unless it were needed with another for proper width (as I indicated above) or required at one end; you may need to experiment with spacer placement.
Posted 04/17/2014 09:27AM
#2
The only thing Meade can help in today's.......NAW! I'm keeping my mouth shut on this joke.
Just a few thoughts:
8) FS-152SV sitting in the office
:S Meade ETX-90 finder scope position
:C SR-4mm eyepiece with a 3x barlow in a 60mm refractor
8O Zeiss Victory 7x42 SFs
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