The Sony FX3 Underwater Review

The Sony FX3 has the Same Amazing Underwater Video Capability as the Sony A7S III in an FX Cinema-Line Body
By Nirupam Nigam

The Sony A7S III was a bombshell camera release for many underwater video shooters. It's been our favorite camera in 2021 for underwater 4K video with a wide range of options for video workflows and post-processing. The Sony A7S III is a particularly capable camera in low light environments, easily capturing clean video at ISOs past 12,800.This makes it perfect for many underwater shooting situations. Shortly following the rollout of the A7S III, Sony announced the Sony FX3 - which is basically the Sony A7S III in a Sony cinema line body. So why did Sony release the same internals in a different body and what does this mean for underwater video shooters?

We decided to keep this review of the Sony FX3 short and not dive with the camera, because everything you need to know about the camera can be read in our Sony A7S III review here. That being said, we do have new information on the A7S III for underwater shooters that explains why the FX3 might be a better option for underwater video shooters. Read below to find out why...

Sony FX3 Status: Available Now At Bluewater Photo

U.S. MSRP: $3899

 

 


 

Underwater housings for the Sony FX3 are available at Bluewater Photo!

Sony FX3 Camera Body

Nautiam Sony FX3 Underwater Housing

 


 

 

Sony FX3 vs Sony A7S III

When we say the Sony FX3 is exactly the same as the Sony A7S III internally, we mean it. They share essentially the same specs, video quality, recording options, etc. However, there have been some changes to the body of the FX3 that orient it for cinema shooters:

  • The Sony FX3 is slightly smaller than the Sony A7S III and lacks a viewfinder
  • The FX3 is sold with a detachable handle. The handle has twin XLR/TRS terminals. These are audio features, and obviously the handle won't be of much help underwater.
  • The FX3 has a zoom lever, but there are only two Sony lenses that will work with this lever - the FE PZ 28-135mm f.4 and the FE C 16-35mm T/3.1. The latter may be useful for underwater video but not the former. 
  • There are multiple tally lights that have been added to the body, so you never have to worry about knowing if the camera is recording. 
  • The Sony FX3 has a cooling fan which will extend recording times. However, overheating is not a huge issue with the Sony A7S III. However, we have had reports that at 4K/120p continuously filmed underwater for 20 minutes, the camera can over heat. So if you want to do a lot of slow motion filming, the FX3 might be a good option.
  • The FX3 body has thread holes for accessories
  • Price: The Sony FX3 clocks in at $3899 whereas the Sony A7S III is $3499. This is likely because of the included handle/XLR adapter

 

Should You Buy the Sony FX3 or the Sony A7S III?

Underwater, many of the differences between the Sony FX3 and the Sony A7S III become a moot point. The handle and XLR adapter and thread holes will not be useful to underwater shooters. It's specifically the handle that comes with the FX3 that contributes to the increase in price. When considering the Sony FX3 vs the Sony A7S III there are two main reasons why the FX3 could be a better choice for a dedicated video shooter:

  1.  The Nauticam housing for the Sony FX3 is actually slightly smaller than the the Nauticam A7S III housing (1.97kg for the FX3 housing vs 2.7 kg for the A7S III houing). Because there is no viewfinder on the FX3, it is not possible to use a magnified viewfinder with this housing for composing. Currently there are no other models available for the FX3.
  2. The Sony A7S III has been reported to overheat when shooting 4K/120p for extended periods underwater (20 minutes or greater). Although most people don't shoot at 120fps for long periods of time, there are some underwater situations where this could be useful if you have the storage capacity. So the addition of the cooling fan could be very useful.

 

Sony FX3 Underwater Housings

nauticam sony fx3 underwater housing

Nauticam Sony FX3 Underwater Housing

There is currently one underwater housing available on the market for the Sony FX3 - the Nauticam FX3 housing. At 1.97 kg it's actually .73 kg lighter than the Nauticam Sony A7S III housing, making it a good option for any video shooter looking to reduce weight. The housing is machined from solid anodized aluminum and includes many of the great features native to nauticam - like their port locking system and compatibility with nauticam optics. The housing is compatible with external monitors for HDMI 1.4 and 2.0 cables and comes with a leak detection system.

 

 


 

Underwater housings for the Sony FX3 are available at Bluewater Photo!

Sony FX3 Camera Body

Nautiam Sony FX3 Underwater Housing


There are many more housing options for the Sony A7S III at Bluewater Photo:

Nauticam Sony A7S III Underwater Housing

Ikelite Sony A7S III Underwater Housing

Sea & Sea Sony A7S III Underwater Housing

Aquatica Sony A7S III Underwater Housing

Isotta Sony A7S III Underwater Housing

 

Order a Sony A7S III Camera Body at Bluewater Photo:

Sony A7S III Camera Body

Read Our Top Sony A7S III Underwater Settings

Check out our full Sony A7S III Underwater Housing Buyer's Guide

 

Contact Us for a Special Sony A7S III Underwater Package

 


 

 

ABOUT THE AUTHOR

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!

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