I posted this question yesterday, but the photos didn't come thru. Here's a second try.
On my first dive trip with the Olympus E-M1 and the Nauticam housing, I had a problem using TTL. I think it showed up the most with medium distances using the 60mm macro lens. I was using two YS-01 strobes.
I have some examples of the problem. All of these are shot with the mode dial on manual. The metering was center-weighted.
Here’s a pair of flamingo tongues that were overexposed when shot at 1/320th and f6.3.
My reaction was to drastically change the f stop, so exposure on the next shot was OK 1/320th at f 14.0:
Same dive, here’s a toadfish overexposed when shot at 1/320th and f 8.0:
Again, I stopped the camera down, and the next shot was OK at 1/320th and f 14.0:
Here’s a shot that had OK exposure at 1/160th at f 6.3:
But then the very next shot (different subject), is way over-exposed when also shot at 1/160th at f 6.3:
The same scene is better exposed after drastic changes to the shutter speed and aperture, this time 1/320th at f13.0:
Any ideas what I was doing wrong? Could I have had the flash setting on “full” rather than “fill”? Would that explain this?