FS5 vs FS7 Shootout: Same Sensor, Same Image?
In this post, we'll be comparing the Sony FS5 to the Sony FS7. Specifically, FS5's 12-bit RAW and the FS7's internal 10-bit 4K.
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For some context, nearly all the DPs that Oxenfree hires are FS7 owners, and in 2018 we invested in the Sony FS5 with RAW as our A camera, and the perfect B camera to the FS7.
It was a really hard decision to make as the cameras in this price range are really competitive. We were considering the FS5, Blackmagic Ursa Mini Pro, Panasonic EVA1, the Cannon C200, and even the FS7. I won't go into the pros and cons of each, but we were upgrading from the Sony A7s II and the Sony A6500. So, keeping the codecs and the colors the same ended up causing us to swing toward the FS5.

In our research, we were amazed by how the later RAW firmware updates transformed the FS5 into a beast of a camera, when used with a 4K recorder like the Atomos Shogun Inferno or the Odyssey7Q+. For an additional $500, the RAW upgrade allows you to shoot up to 4K RAW at 120 frames per second in a four second burst, 4K RAW at 60, 30, and 24 frames per second continuous, and 2K RAW at 240 and 120 frames per second continuous. Not to mention that the FS5 can already internally record 10bit 1080 at 120 or 240 frames per second in burst modes or a 120 continuous with another paid upgrade.

One fact that caught my eye when researching these cameras is that the $4,300 FS5 and the $7,000 FS7 share the exact same sensor. Actually, the same sensor as a lot of the Sony cinema cameras. The main difference is the codecs and how the camera processes the images internally. The FS5 uses XAVC-L and the FS7 uses XAVC-I. Now, all of these cameras sharing the same sensor is so intriguing to me because of the easy to access RAW capabilities of the Sony FS5.

My hypothesis, and reason for this post, is that if the two cameras have the same sensor, if you bypass the internal computing and the codecs by shooting RAW, you should have the exact same image.

Now, to add RAW to the FS7, you have to buy an additional $2,000 extension unit as well as having an external recorder. Being budget conscious in my test, I'm more testing the FS5 with the RAW upgrade, a $4,800 package, versus the FS7 out of the box shooting in it's internal 4K 10bit which is a $7,000 package.
As a disclaimer, there are a lot of reasons to pick an FS7 over the FS5. We will mainly be looking at image quality while keeping the cost in mind. However, this should be a little unfair of a contest as we'll be shooting 12bit RAW on the FS5 and only 10bit internal on the FS7. We should really notice it in the colors and the natural gradients from light to dark or from one color to the other.
I won't guarantee that our tests are the most scientific but we did our best to keep all the variables the same. Both the FS5 and the FS7 were on tripods right next to each other, set to S-log three, ISO 2000, and switching the same Sigma Art 50 lens between them. We changed the aperture from 1.4 to 5.6 to change the exposure stops from two under to two over. With all that being said, here are the tests.