Instrument To Measure In Tenths Of A Millimeter?

How would one go about measuring something on a stamp - say the length of an overprint or the distance between letters - in tenths of a millimeter? I recently purchased a set of the Germany Philatelic Society's Forgery Manuals, and on some issues one of the markers to look for is the measurement of certain features down to the tenth of a mm. Is there scanning software that will do this, or is there some sort of electronic device, perhaps? Anything that would rely on human eyesight in any way would be inherently inaccurate at that level of precision, so I know that something like calipers wouldn't work for that. Just wondering if anyone has any ideas.

In biology I've used a microscope with a minigrid which is a glass slide that essentially is very fine graph paper that goes down to 100 um which is one tenth of a millimetre. You may be able to use the minigrid on a scanner and align the stamp next to it or place the stamp under it.

Stephen

I have a USB Dino-Lite Pro handheld digital microscope designed with a high quality 1.3 megapixel image sensor that lets you view and capture objects with the greatest of details and has the software that enables one to take angle, line, circle, continuous line, radius circle,diameter circle, and 3 point circle measurements. It can view objects at various magnifications depending of distance with a max magnification of up to 220X. Also has near UV. See site for user manual below. It is very pricy however-look around on internet for best deal.

http://www.minresco.com/dinolite/di...%20Guide.pdf

That 'mini-gird' is a/k/a 'reticle', as in:

http://www.edmundoptics.com/microsc...ct-reticles/

For economy-in-philately, you'd buy the set:

http://www.edmundoptics.com/microsc...le-sets/2023

I've used their millimeter-scale reticle; don't know about 100-micron-scale.

The higher the magnification, the smaller the FoV (field-of-view).

In practice, that means that it can take some fiddling to find the detail that you want to measure.

If you do not need portability, and have the cash, I'd go with Albert.

Cheers,

/s/ ikeyPikey