Hi everybody and glad to be here again,

I have a system of lens and wanted to remake them one by one from polycarbonate (or other transparent and easily available materials) but want them to have 4 times shorter focal length (advice given by the gentleman Nodda Duma).

My question is that I can, based on lens making formula, change the R1 or R2 and the thickness and I do not know which one I should consider.

Any hints or advices?

I have access to 3d printers and CNC and zeemax software at my workplace.

Thanks a lot in advance