the lens would shift in the cell. However, not all had this problem. Might have been the slop in their milling machine that caused all the issues. Maybe more than on shop was making the lens cells. Mine was shipped cross country and was fine. Guess I was really lucky. Was a great scope. I miss it.
I don't believe it was slop. It was how the lens elements were designed. The lens elements had steep curves and probably a wider air gap than a normal doublet. This was done to get reasonable color correction using a less expensive ED glass and only using a doublet instead of a triplet. Later lens cells had lens alignment screws. These are not collimation screws but are used to align the two lens elements themselves, keeping the lens elements centered. The original cell for the 7" could not even keep the lens elements aligned during shipping. And the hassle of packing and shipping a 7" refractor back to Meade cannot be overstated.
Some may have gotten a 7" with the cell fix. But even then, I would not want to have to spend thousands on a large refractor and possibly have to deal with aligning lens elements somewhere down the road. The smaller sizes seem to fair better.
The 7" might be fine for those that want to pick up an inexpensive used sample and spend the time tinkering. But if you want a larger refractor that will work properly right out of the box without taking a chance, look elsewhere.
There's a reason that these Meade doublets had a short lifespan in the marketplace.
Agema now makes large doublet apo refractors but their lens cells are a lot more robust. And in order to get better color correction, they use a unique lens design that incorporates Fluorite as the ED element. These Agema refractors are not inexpensive.
Bob
