Old Bishop Graphics 10x loupe
I usually use the magnifying glass on my Swiss Army knife to inspect PCBs. It is an older 8x magnification model with the grey plastic housing. They don't make them anymore. The new Victorinox knives have different lenses that are only 5x or 6x magnification. The older 5x ones are plastic and are junk. The current 6x lenses are glass but they pop out of their frame and I have already lost one.While looking for a replacement I found these Bishop Graphics 10x loupes on eBay. They are probably 25+ years old. They are made by Peak and the equivalent model is around $89 on Amazon. The Bishop Graphics one comes with a No 5 measuring reticle that is another $20 on Amazon.
These are shelf worn. The pleather cases are worn. There is a little oxidation on the shiny parts of the aluminum. The glass is perfect. The focus mechanism is still tight and smooth. Feels like a high quality all metal and glass SLR lens. Functionally these are in perfect shape.
For the price, these were a steal.
The irony is that Bishop Graphics was a company that made supplies for PCB design. This was when it was a manual process done entirely by hand. I found some interesting articles on Adafruit and LA Times.
The loupe was intended to look at flat objects on a light table. There is very little distortion or chromatic aberration on the edges. You can use it upside down to look at odd shaped objects.
The reticle is removeable. The No 5 reticle has many useful scales. They make a few other reticles with different patterns.