When combining a borescope (industrial rigid endoscope) with a camera, inserting a macro ring allows for magnifying the image.

However, inserting the macro ring shortens the focal length. While you can adjust to some extent with adapter lenses, there are limitations. Additionally, magnifying the image can result in decreased brightness, necessitating a sufficiently bright light source.

I tested the effect of the macro ring with a focal length of 5mm.
(Photographed graph paper with 1mm pitch.)

– Without macro ring

 

 

 

• 5mm macro ring

 

• 10mm macro ring

 

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