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    Re: Dioptric correction
    From: Norm Goldblatt
    Date: 2013 Jan 21, 13:11 -0800

    Thanks, Frank, yet again.

    I'll do just that. I've been able to disassemble everything except one objective on one of the tubes. The long tube has a lens inside, just in front of the reticle. I'm assuming this is an erector. I can measure the focal lengths of the lenses quite accurately, using the Sun. So far, the correct pairing eludes me, but I'm sure it will all come together.

    There are no negative lenses in any of the scopes, so I'm assuming that none are Galilean and hence all are inverting, except for the long telescope with the internal lens.

    Yes, both sets of reticles are intact, which pleases me. I'll be very careful not to damage them.

    Any suggestions for unfreezing brass telescoping joints without any discoloration?

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