For no particular reason, I built a lens for my Graflex. All parts are from the local hardware store.
Here are some links I promised:
Measuring lens aperture: https://apenasimagens.com/en/measuring-lens-aperture/
About entrance pupil diameter: https://youtu.be/OaSq0ES1ArE?si=L7tNEwmjeUoAvYWD
I built the entire SLR camera: https://youtu.be/dEGXORWi2lU?si=uzNu8YPGSCzgI3nI
I made a lens: https://youtu.be/2J22KJFVzRI?si=rsQYMC-ExhTKKjJ1
I made a pinhole camera from a ukulele: https://youtu.be/IFNWP27y8X0?si=vdyIpGP2h8mPav8g