Testing FP4+ sheet film stand developed in Rodinal 1:50. This image is a 1/3rd crop of the negative.

With a nod to Fibonacci.

Ilford FP4+ 4x5 sheet film, exposed at iso200, 7 seconds at ƒ22 (dark room, only window
providing late afternoon sidelight), selecting Rodinal 1:50 dilution, and stand developing
for 20 minutes at 20C, after a minute of gentle inversions. To permit 'daylight' processing,
I placed two 4x5 sheets for development in a 120 development tank (800ml) without the spiral
fitted, but with the central spindle. The sheets were gently loaded in the dark, emulsion inwards,
semi curved around the sides (a perfect fit). They did not move during inversion, and were both
evenly developed, front and back. I removed them (in the dark) for stop and fix in trays, rather than empty and fill.