I think this item on amazon is sort of what you are looking for
iGaging 36-LED10 Stand Measuring Magnifier, Loupe 10X with Scale LED Lighted Illuminated
Here's the one I have. It has two scales that measure either up to one inch or 25 millimeters. It folds flat. I bought it many years ago at Hobby Lobby. There is no name on it on which company marketed it. I prefer a standard jeweler's loupe, but like you said, it only goes up to 20 mm.
There are similar folding magnifiers available.
RDGTOOLS-FOLDING-MAGNIFYER-WITH-SCALE-MAP-READING-INVESTIGATIVE-WORK-EYE-LOUPE
The ones that nlroberts refers to are impressive.
I use one similar to the second one pictured which I purchased from Peak Optical. It was not cheap, but the scale on the reticule has a total length of 30 mm (and is marked at 0.1 mm intervals.)
Jan
If you want one for exacting measurements, you have to pay for that.
I would definitely want one that could measure to 0.25mm minimum.
Has anyone ever used one of these two items? I am looking for something like this but the scale needs to be at leaast 22 mm, and I can't find in the specifications on all the different ones what the max scale is.
Has anyone seen one with a scale of at least 22 mm?
re: Measuring Loupe
I think this item on amazon is sort of what you are looking for
iGaging 36-LED10 Stand Measuring Magnifier, Loupe 10X with Scale LED Lighted Illuminated
re: Measuring Loupe
Here's the one I have. It has two scales that measure either up to one inch or 25 millimeters. It folds flat. I bought it many years ago at Hobby Lobby. There is no name on it on which company marketed it. I prefer a standard jeweler's loupe, but like you said, it only goes up to 20 mm.
There are similar folding magnifiers available.
RDGTOOLS-FOLDING-MAGNIFYER-WITH-SCALE-MAP-READING-INVESTIGATIVE-WORK-EYE-LOUPE
The ones that nlroberts refers to are impressive.
re: Measuring Loupe
I use one similar to the second one pictured which I purchased from Peak Optical. It was not cheap, but the scale on the reticule has a total length of 30 mm (and is marked at 0.1 mm intervals.)
Jan
re: Measuring Loupe
If you want one for exacting measurements, you have to pay for that.
re: Measuring Loupe
I would definitely want one that could measure to 0.25mm minimum.