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MM3/4 50ED stay on case (1 Viewer)


Having read various comments about how difficult it is to fit the opticron stay on case to the 50ED scopes but wanting a stay on case I decided to brave fitting the case and ordered one for my MM3 50ED from Uttings.

The case arrived yesterday (I bought the green case) and I don't know if they have recently changed the design of the case but it went straight on to the scope with no bother, issues or struggle whatsoever. Phew...….

At the same time I bought an 40831 HDF Eyepiece. I wanted a fixed focal length eyepiece to get a wider field of view but do not need a very high magnification so the 18x of the 40831 is good for me. I have briefly tried the eyepiece and think is an optical improvement over the eyepiece that came bundled with the scope. It also has a twist up eyecup which is a huge improvement over the fold down rubber eyecup of the bundled eyepiece.

Merry Christmas and a very happy New Year to you all.

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Well-known member
I've had the ED50 and green cover for several years now. The cover fits the scope tightly, is well constructed and made of very stiff material. One flaw is that the thick flap that covers the focus wheel will not stay gripped in place, a constant annoyance.
Re the eyepiece, ours is the 40862 zoom. Rotating the twist out eyepiece also moves the zoom control a small bit, a minor fault that you will likely avoid with the fixed length.



Well-known member
Does anyone with a MM3/4 and stay-on-case have the following issue?
The case does not fit tightly enough around the upper side of the thinner barrel/body part below the focussing knobs: it 'floats' against the focusing knobs. As a result, the focussing knobs rub against the upper/exterior side of the case when turned. This blocks the fine focusing knob from turning along with the coarse focussing knob, when using the coarse focussing knob with the stay-on-case on. This does not reassure me: I'm not sure if that could put stress on the focus mechanism.
Would there be a mistake with my stay-on-case, or a general design mistake of the stay-on-case, or is this no problem for the focusing system?

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