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.)

 

 

@Jim M. I had the EM-5 and EM-1 mark 2, and while I love the size of the cameras and lenses, shooting tiny fish moving was a challenge. It really came down to the fish momentarily stopping, then firing the shutter. If you've never used Sony cameras, their continuous tracking autofocus is amazing.

@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.)

Edited August 15, 20241 yr by Jim M.

Probably not many who have shot both your candidate cameras.  Probably also depends on which lens you are using. 

 

I shot for some time with the EM-1MkII and found the AF pretty good and used C-AF plus tracking UW.  I'm now using the OM-1 UW and it seems to snap into focus fairly well, I find C-AF works quite OK.  Much of my shooting is on reefs around Sydney in temperate waters where mild surge is a near constant challenge.  I get a decent hit rate on tiny pygmy pipe horses swaying in the surge among weed, hydroids and other fixed life.  I don't shoot a lot of fish portraits but when I do I seem to have a reasonable hit rate, mostly with the 60mm macro lens.

 

Here's a larger fish, a Rainbow Cale, about 180mm long, shot with OM-1/60mm macro 1/160 @f10 ISO200:

 

And here's some southern Hula fish, same setup and settings, these little fish about 80-100mm long squirm a lot as their name suggests.  my hit rate on them is probably not as high:

 

Last, here's a pygmy pipe horse, which was swaying back and forth in the surge along with the growth you can see in the shot, these are about 50mm long and 5-6mm diameter.  Same setup/settings:

 

I have the OM1-mks I and II, and while I've used the mkI underwater I don't have a ton of reps with it yet.  I can say that both do very well with subject detect topside.  I've heard that subject detect works well underwater, and my recommendation would be to set it up for a medium sized box.  Meaning, not the smallest single focus point, but the box that takes up about a third of the frame.  This will limit unintended targets, and I would also suggest using the focus limiter to keep the camera from hunting outside of your viz limit.  Prior to the OM1s, I shot the E-M1mkIII underwater and I too seem to gravitate towards fish portraits.  That camera did just fine locking on to my intended target with C-AF, and based on topside experiences with all 3 bodies, I can't imagine the OM1s would do anything but improve the hit rate.

11 hours ago, Jim M. said:

@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.)

That sounds great. One day I may move back to OM System. Great ergonomics. Good color science. Nice system.

 

A firmware update was made available for the OM-1 mk1 a couple of weeks ago, with the main improvement billed as subject acquisition in “all-target mode.”  I don’t use that mode, but have found the OM-1 to focus well both above and below the surface with busy backgrounds, particularly with subject detection (bird eyes and fish eyes aren’t so different).  

I noticed an improvement shooting tiny bugs recently after upgrading firmware on my OM-1, it grabbed the bug and found the eye quite well.  It's better than what I remember it doing.

I can confirm bird detection in OM1 mk1 works fairly well for fish eyes. I used that with a medium sized C-AF zone.

Just in case, I configured a button for switching on/off the subject recognition, and use the 1/2 lever for changing from single point to medium size or cross focusing area.

The OM1 has some of the best autofocus I've used underwater. It is remarkably good. However, for 1/5th the price, the em10 IV gives 90% of the performance (imo). If budget isnt a concern, the om1 is definitely better. But it is not a night and day difference.

 

https://www.divephotoguide.com/underwater-photography-special-features/article/review-om-system-olympus-om-d-e-m10-mark-iv-backscatter-octo-housing