I have a Beck long arm engineering/measuring microscope with an engraved graticule; two really, one is measurements on a round glass disk, the other a straight line on a sliding glass block coupled to a micrometer adjuster.
The lines are very feint and hard to see against anything other than a pure white background.
Does anyone have any ideas on how to re-ink them?
The lines need to be fine, as the micrometer measures, with these optics, down to a tenth of a thou.
Not my own photo, taken from the listing
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Cheers Bill