Sony A6500 or A7iii to photograph whales underwater?

Miguel_A81 wrote:

I am planning on going to Norway to photograph whales underwater.

I currently have a Sony a6500 and was thinking of getting the Sigma 16mm 1.4 to be able to capture the whales with as much light as possible.

Now, I'm wondering if getting and using the Sony A7iii (with perhaps the Sony 24mm 1.4) would make a difference in terms of image quality, sharpness, etc...?

I'm no pro by any means, but I do want to be able to capture the best possible images since it's a once in a lifetime opportunity for me!

I'm also wondering if the underwater housing has any effect on the image taken depending on the brand? Or in this aspect they are all the same?

It's more about the ports that housing lets you use that can impact quality. This is the main knock against the cheap housings, and sometimes the OEM offerings. Nauticam, Aquatica, etc will use extensions specific to each lens so that the lens to glass distance is most conducive to IQ.

As B already noted, for rectalinear lenses, the bigger the better is usually the came for domes, though the cost and the travel hassle grows rapidly as you go from the 6 to the 8 to the 9.5" choices.

Now frankly, getting the best possible images depends much more on you than on the equipment, given you're already at an APS-C sized sensor. Switching to new gear you're not familiar with may be counterproductive. Unfortunately, hard to practice for. But if you go that route, for a 'once in a lifetime' type trip, you should also look to costs and choices available to you as a rental. If you can get the trip organizer to provide the gear, even better. You can still bring your existing equipment as alternate or fall back. Don't invest a lot for a single trip and end up with gear of limited added value going forward. Esp when there's the chance you could get skunked - bad weather, unsocial whales, etc.

Also, if cold water is not normally your scene, spend time thinking about best suit choices and how that impacts you otherwise.    Will you need to wear gloves ,and is that unusual for you?  I don't wear gloves unless the water temp goes below 11C/52F.   This at least you can practice with in a pool or even sitting on the couch to some degree.

Next step for you I think is to look for prior participants reviews and galleries. You're looking for the ones that describe the photographic challenges/successes, or at least tag their images with the lens choice and exposure settings. In particular, you want to see how close the whales get, and how well that fits in the frame. That can affirm or counter your gear or considered options.

It's a bit striking, and unfortunate that there are no fisheye choices available for Sony. For massive subjects that can get close, it's often the only viable choice. The compactness of the port is also a boon when you're dealing with currents or are snorkel based chasing the moving animals.

I spent the first week of December at Tiger Beach. Using a 4/3rds, I split time between the 8mm fisheye (4" dome), and the 7-14 rectalinear (with a 6" dome). Having both was right for this trip, but the fisheye generally was more productive as the sharks frequently came to point blank range and one even took a bite at the 6" dome. Other times the distance was 10-15 feet and fisheye was no longer as good. The 7-14 could still fill the frame, however the distance and the silting often still meant a lower impact image. As always with UW, close is usually best.

Now in contrast, last year I was at Guadalupe with the white sharks and they rarely got so close. I exclusively shot with the 7-14 I had just gotten....without it the trip would have been a big fail on the photographic side. My wife did very well with a compact (G7XII) and a tiny "wide" angle nauticam port that just restores normal 24mm width. Ended up being perfect for 10-15' sharks at 15-20' distance.