The Sony Alpha a6400 stands in the middle of Sony's 2019 compact mirrorless line-up, between the more economical a6100 model and the newer, more robust a6600.
The a6400 has great battery life and is an excellent choice for underwater video. Most of us enjoy the flexibility of switching between video and still while underwater, and the a6400 provides strong results either way. Sony's autofocus system is class-leading topside but does struggle a bit in the lower light environments we find underwater.
"The redeeming quality of the a6400's autofocus is the tracking ability. Sony has integrated artificial intelligent technology into their autofocus system to track the eyes of not only human subjects, but also animals! And despite slow underwater autofocus speeds, we found that it worked great. I had multiple macro shots saved by the animal eye AF tracking, when I was able to capture the eyes of a fish that moved at the last second. It doesn't work 100% of the time, but if you're on the correct focusing plane to begin with, it works."
- Nirupam Nigam in his review of the Sony a6400 camera
Nirupam took the a6400 into the waters off the US Pacific Northwest to see what it could do with a variety of lenses including the Sony 10-18mm, 16-50mm, 50mm Macro, and 90mm Macro.
These photos were taken with Ikelite DS161 strobes in TTL exposure mode.
All images copyright © 2019 Nirupam Nigam
Nirupam Nigam is a dedicated underwater photographer and fisheries scientist. While growing up in Los Angeles he fell in love with the ocean and pursued underwater photography in the local Channel Islands. He received degrees in Aquatic and Fisheries Science and General Biology, as well as a minor in Arctic Studies, at the University of Washington. Now he works as a fisheries observer on boats in the Bering Sea and North Pacific. When he is not at sea, he is traveling with his fiancee and taking photos. Check out more of his photography at www.photosfromthesea.com!
Additional Reading
200DLM/A Underwater Housing for Sony Alpha a6300, a6400, a6500 # 6911.64
First Look Sony Alpha a6400 Underwater Housing
DL2 DS Link Sony TTL Converter Underwater Photos