Jim M.

@humu9679 Thanks for your input. At this point, I'm only interested in the two Olympus/OM camera alternatives I mentioned. Have a trip coming up soon. (Above water, I've seen the OM-1 has significant improvements over the EM-1 mk 2 in terms of AF; I believe it is similar to the Sony in terms of tracking.)

Hello, I own both these cameras, but have never used the OM-1 underwater. I really like the light weight, compactness, and simplicity of the EM-10 for use underwater, while still offering an excellent, fairly large sensor. But I'm considering, somewhat reluctantly, getting a housing for my OM-1. It will cost over a grand and increase overall weight by about a pound, but it would be worth it to me if it would significantly decrease the number of missed focuses I get when shooting fish moving against a busy background. I shoot a lot of fish portraits, and my focus hit rate with fish moving against busy backgrounds is only about 50%. (I use continuous autofocus without tracking and the smallest autofocus point; my impression is tracking doesn't help for fish). But I don't really know whether the OM-1 will be a significant improvement – because that context is among the most challenging for any autofocus system. And I know that above water the OM-1 struggles (as do all cameras) with birds flying against a busy background. The OM-1 would also have the advantage of providing the option for custom settings, and perhaps different settings for different contexts would also be helpful, e.g. a bigger autofocus area and use of bird/creature detect AI for smaller fish in open water. (My impression is that the autofocus AI won't help with fish against busy backgrounds because it will program to lock onto the wrong subject.) Anyone have opinions on whether the OM-1 would significantly reduce missed focuses in the busy background context? And does anyone have experience shooting fish with both cameras? (I put more weight on practical results rather than theoretical advantages – because I find autofocus systems tend to be overhyped.)

I am recently retired and an amateur naturalist and wildlife photography enthusiast. I love to document all the living critters I encounter, both large and small. Been photographing stuff most of my life. Intermediate level when it comes to underwater photography--which I do mostly while snorkeling in exotic locales. Most of my experience has been with micro 4/3 system cameras.