Canon G7X Mark III is an excellent, first-rate camera in a small body. It is an upgrade from the famous G7X Mark II, the Mark III incorporates a similar sensor and the same lens, but there have been significant improvements to the camera’s processing capabilities. Specifically, the camera now features a “stacked” sensor and a DIGIC 8 image processor.
Updates in the G7X Mark III's hardware resulted in an improved burst shooting rate (now 20 fps), 4K video capability (no crop!), improved image buffer (now 70 shot RAW), and slow-motion video in 1080p. Although the image quality remains the same as the G7X Mark II, these improvements will give underwater photographers new creative tools.
The G7X Mark II led the compact camera market for the last two years. But a lot of has happened in two years, especially when you look at Canon’s competitors – the
Sony RX 100 V/VA and the Sony RX100 VI and even the Olympus TG-6. That being said, the G7X Mark III is definitely the camera to bring Canon back to the future. We took this camera underwater in the cold waters of the west coast and put it to the test. Overall, we were happy with the image quality of this camera, and especially the new ability to process 4K underwater video. We jumped at the opportunity to take some 4K video, so be sure to check it out below.
U.S. MSRP Canon G7X Mark III: $750
Ikelite Canon G7X Mark III underwater housing with dual Ikelite DS 161 strobes, and some Sola Lights. Ready to dive!
Canon G7X III compared with G7X II
The upgrades on the Canon G7X Mark III from the G7X Mark II will be welcomed mostly by video-shooters and vloggers. There were a few improvements made to the camera that are exciting for underwater photography – most notably when it comes to 4K video, slow motion video (@1080p) , burst shooting, buffer, and the new stacked CMOS sensor.
Canon G7X Mark III Specifications
Key Upgrades from the G7X Mark II
• 4K video @ 30fps and 1080p @ 120 fps
• Built-in Bluetooth and WiFi
• Ability to shoot panoramas
• External microphone jack
• 20 fps burst mode (upgraded from 8fps)
• 70 shot RAW buffer (upgraded from 21 shots)
• Ultra-fast electronic shutter for shooting wide open aperture in daylight – 1/25,600s
• Slow motion video (120 fps in 1080p)
• Supports vertical video shooting (not for live-streaming)
• Supports live streaming videos to YouTube
• Cheaper than the Canon G7X Mark II on release date
• 3.0 inch touch panel LCD screen with tilt option of 180 degrees for selfies and vloggers
• Compatible with USB charge/power supply
• Contrast-detection autofocus (no dual pixel autofocus)
• Clean HDMI output
• Native ISO: 125 – 12,800
• Size: 4.1” X 2.4 “ X 1.6 “
• Weight: 11.3 oz (319 g)
Nauticam G7X Mark III Underwter Housing
Improved Video Capability
The G7X Mark III’s most enticing update by far is its new and improved video capability. 4K video capability in most cameras is standard here in 2019. Canon brought the G7X III to the present with 4K capability at 30 fps. It’s a relief that there is no 4K crop factor, so the full potential of the sensor is utilized resulting in crisp video details. Slow motion video capability (120 fps) is available at 1080p. This will be great for any underwater photographer looking to capture quick moments underwater – like schools of fish, dolphins, sea lions, sharks, etc.
There have also been some exciting updates made for topside photographers as well. The G7X Mark III now supports video live streaming on YouTube as well as vertical video shooting.
Canon G7X Mark III Sample Video
We took the Canon G7X Mark III deep into the cold waters of the Hood Canal in Washington State, USA. It was the perfect place to test the Canon G7X Mark III's low light video and autofocus capability. We thought the camera performed really well and that the video quality shows a significant improvement from the Canon G7X Mark II. In fact, this is one of the top improvements of the Canon G7X Mark III. The 4K quality is really detailed and it's nice to have a camera from Canon where there is no crop factor in the 4K video. This video features underwater life native to the Pacific Northwest, including wolf eels, metridium anemones, zoanthid anemones, and sunflower stars.
Improved Photo Capability
There are a number of improvements to the G7X Mark III’s photography processing; all of these improvements are a result of the new 1-inch stacked CMOS sensor and the DIGIC 8 processor. Although the new sensor seems similar to the sensor on the G7X Mark II, the “stacked” design means that it has one layer for collecting data and one layer for processing. This results in the camera having more ability to process images. The G7X Mark III’s burst shooting capability has been improved from 8 fps to a whopping 20 fps - that's better than many full-frame systems! The RAW buffer has also been improved to 70 shots from 21. This is very exciting for underwater photographers who want something small that can capture fast animals underwater. So what exactly does all of this translate to? Well, you can shoot RAW at 20fps for just over three second continuously before the camera needs to take a break to process. That’s perfect for getting dive bombed by a cormorant or passed by a sea lion. Unfortunately, burst shooting is only 8.3 fps when shooting with continuous AF, not that 8 fps is slow…
Side note: The G7X Mark III has also been updated to shoot Panoramas! Not the most useful feature for underwater photographers, but very cool nonetheless.
A nudibranch photographed with the Canon G7X Mark III in the Ikelite G7X III housing with dual Ikelite DS 161 strobes. f/11, 1/160, ISO 400
Canon G7X Mark III Key Features
Body and Build
At 4.1” X 2.4 “ X 1.6 “ and weighing in at less than 1lb, the Canon G7X Mark III is a very compact camera. It’s hard to find many cameras smaller and more compact to bring underwater. For many divers, the size of the Mark II is one of its main selling points, and this will likely be the same for the G7X Mark III.
The G7X Mark III also features a 3 inch touch screen LCD that can be flipped up by 180 degrees for selfies. Canon is trying to appeal to the vlogger market with an external microphone jack and built-in WiFi/Bluetooth. Moreover, G7X Mark III's 3 inch touch screen LCD can be flipped up 180 degrees for selfies
The Canon G7X Mark III shares a contrast-detect autofocus system with the Mark II. Although it’s very functional, some people had high hopes that Canon’s famous dual pixel autofocus would be included. We’ll just have to wait for the next iteration!
When we took the G7X Mark III underwater, we found the autofocus to be very accurate and on par with other top compact underwater cameras. It is a little slower than on other Canon cameras with dual pixel AF, but not too slow at all. This can be noticed mostly when shooting video. However, you can argue that slow and accurate changes between autofocus points with little to no hunting yields a more cinematic video.
A close focus wide angle shot of a diver and zooanthid anemones with the Canon G7X Mark III in the Ikelite G7X III housing, Kraken KRL-01 wet lens, and dual Ikelite DS 161 strobes. f/7.1, 1/100, ISO 400
Sensor and Image Quality
There has been an upgrade in the sensor of the G7X Mark III, but not a huge one. Although the new “stacked” CMOS sensor improved image processing, it doesn't necessarily improve image quality. The Canon G7X Mark III’s image quality is similar to the Mark II. That being said, the image quality is still excellent – 20.1 MP is impressive for any compact sensor.
The lens on the Mark III appears to be the same as the Mark II, which means it is versatile for both wide angle and macro underwater photography – especially with wet lenses. We found it to be excellent in both application underwater. In fact, we were really impressed with it's macro capability.
Zooanthid anemones with the Canon G7X Mark III in the Ikelite G7X III housing, Nauticam CMC wet lens, and dual Ikelite DS 161 strobes. f/11, 1/160, ISO 400
G7X Mark III for Underwater Photography
The Canon G7X Mark III is one of the best choices for underwater photo and video in the compact camera market. The G7X line is now modern with 4K video recording, quick burst modes, and large buffers.
Ultimately, underwater photographers will benefit with upgrades in processing and have newfound ability to capture quick subjects, whether it's slow motion video or burst shooting. The controls are ergonomic with aperture and shutter speed at your fingertips and ISO one tap away. Underwater macro and underwater wide angle shooting is bound to be a joy with the G7X Mark III’s zoom lens, especially with accessories like wet diopters and wide-angle wet lenses.
Pacific Northwest reef scene with the Canon G7X Mark III in the Nauticam G7X III housing, Kraken KRL-01 wide wet lens, and dual Sea & Sea YS-D1. f/3.5, 1/80, ISO 400
Canon G7X Mark III Underwater Lenses
Wide-Angle Wet Lenses
A wide-angle wet lens increases your field of view, which means that you get more background behind your subject and must be closer to it.This means that you will often get less water between the camera and your subject than if you did have a wide anlge lens. Less water means a clearer subject, as well as better lighting from a video light, photo light or strobe....and ultimately better colors. A wider angle also allows for more dramatic shots, especially with large subjects like oil rigs, kelp forests, large animals, reefscapes and wrecks.
Pacific Northwest reef scene with the Canon G7X Mark III in the Nauticam G7X III housing, Kraken KRL-01 wide wet lens, and dual Sea & Sea YS-D1. f/5, 1/100, ISO 320
Macro Wet Lenses
Although the Canon G7X Mark III has a macro mode, the best option for underwater macro photography is to use a diopter. The
Bluewater +7 macro lens gives very good results. We recommend stacking 2 of these lenses for supermacro. The Nauticam CMC-1 and CMC-2 will also work great with this camera and offer more zoom than the Bluewater +7. They can also be a little trickier to use.
Coonstripe shrimp with the Canon G7X Mark III in the Ikelite G7X III housing, Nauticam CMC wet lens, and dual Ikelite DS 161 strobes. f/11, 1/160, ISO 400
Canon G7X Mark III Underwater Housings
Many top underwater housing manufacturers have already developed a housing from the Canon G7X Mark III or have something in the works! The Canon G7X Mark II housings do not work with the Canon G7X Mark III due to differences in button design. Please feel free to contact us at
firstname.lastname@example.org to see what housing will work best for you.
Currently housings have been released from Ikelite and Nauticam. We also anticipate a housing from Fantasea and Isotta:
Ikelite is known for making top-of-the-line ABS-PC blend (polycarbonate) housings. This housing is small, lightweight, and features excellent underwater buoyancy underwater that will keep your arms from tiring while using the G7X Mark III. The ergonomics on the housing are great with fully functional dials and buttons. Ikelite has even created a fiber optic converter so that you can use your housing with Ikelite strobes. The housing has ports for Sea & Sea type fiber optic cables.
Nauticam is known for producing extremely high quality and ergonomic aluminum housings. The Nautican Canon G7X Mark III is small and light weight with easy-to-use buttons and controls. If you're an underwater videographer, you will be excited to know that this housing supports HDMI output so you can pair your camera with an external recorder/monitor. The housing also includes a vacuum valve and leak detection system.
Fantasea underwater housings are compact, lightweight, rugged, and stylish - and made of top-quality polycarbonate for any budget. The Fantasea Canon G7X Mark III housing is designed with excellent ergonomics and labels on every button for easy control identification. All controls are within a finger's distance and easy to operate. Fantasea housings are also reasonably priced and will not break your bank.
Sample Images from the G7X Mark III
Nudibranch gills photographed with the Canon G7X Mark III, Ikelite G7X Mark III housing, dual Ikelite DS 161 strobes, and Nauticam CMC. f/11, 1/160, ISO 400
Coonstripe shrimp eyes photographed with the Canon G7X Mark III, Ikelite G7X Mark III housing, dual Ikelite DS 161 strobes, and Nauticam CMC. f/5, 1/160, ISO 400
Squat lobster photographed with the Canon G7X Mark III, Ikelite G7X Mark III housing, dual Ikelite DS 161 strobes, and Nauticam CMC. f/5.6, 1/160, ISO 400
Wolf eel photographed with the Canon G7X Mark III, Nauticam G7X Mark III housing, dual Sea & Sea YS-D1 strobes. f/11, 1/125, ISO 400
The Canon G7X Mark III is the long-awaited successor to the highly-successful G7X Mark II. While it faces tough competition from the Sony RX100 VII and Sony RX100 V/VA, it holds its ground with the addition of 4K video, 20fps burst, and a 70 shot RAW buffer.
The new 1” 20 MP “stacked” CMOS sensor is bound to deliver great image quality with improved processing ability. What more could you ask for in such a small, easy-to-use underwater package?