I just got a JMI Next Gen focuser. A "real" DRO for this unit costs more than I paid for the focuser, so being inherently "Scotch" I set about finding an alternate solution. On Ebay I discovered machinists "Indicators"! These are devices used to measure changes in distance, consisting of a spring loaded plunger and some sort of read out. They come in analog dial indicators and in digital forms. I found a small digital with 1/2" travel (same as focuser) that has a small form factor that can almost certainly be mounted on the focuser. Cost $39. See pic below. I'll post some pix and ideas when it arrives. I just got excited and wanted to share the love!
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