@Paul Kay
A few months ago, I decided it was time to find out ,what would be optimal underwater performance of my particular lenses in my particular dome ports. So, that meant the tedious trial and error of pool testing with a variety of lenses, ports, port extension, and diopters. I even borrowed some lenses from Canon Professional Services to test a few lenses I did not own. Show here are::
* Canon EOS1DsMKII
* Sea cam housing with wide port, fish eye port, and super dome (S45 viewfinder)
* Port extensions from PVL25mm through PVL55mm
* +1, +2, and +4 diopters
* Canon lenses 15mm, 14mm, 16-35mm, 17-40mm,
20mm, 24mm F-1.8, 35mm F1.8, and 24-70mm zoom
Thanks,
