Measuring pics with curve another measure thread

Ok I know another measuring thread, There is threads out there for measuring or not measuring curves, measuring vertical or tape vs ruler and on and on but I can’t find what I’m looking for.

Ok I have been measuring with the vertical ruler method for years thanks to this thread and others=
Suggested new measuring method: vertical ruler

I have recently been trying to get good pics of my BPEL and realised there is quite a gap between my penis and the ruler because of the curve, From what I’ve read more people believe measuring the curve is accurate. It’s quite difficult to hold the penis against the ruler and take a pic and I’ve not seen anyone doing it. Do you guys do it this way or just measure and take pics with the gap? I ask the question because allot of threads are old that I’ve been reading.
I really want to start document my journey, I’m doing the same with my body and have been for a while and its a great help having accurate pics to see where changes have happened and what needs to happen.