The Canon EOS R3 seemed like the mirrorless entrant to the 1 series, but Canon assured us that it was not.
However, it was the former performance leader of Canon's MILC lineup.
The R1 now shadows the R3's performance.
Check out the R1 vs. R3 specification comparison
along with the visual comparison of these cameras.
What are the differences between the Canon EOS R1 and the R3?
Here are the R1's advantages:
- 40 fps for 230 RAW frames vs. 30 fps for 150 (having faster continuous shooting available is an advantage, but 30 fps is really fast, and 150 is a lot)
- Custom high-speed continuous shooting supports higher frame rates
- 2.7 ms imaging sensor readout speed vs. 4.8 (faster is better, but this difference will seldom be noticeable)
- ISO expansion up to 409600 vs. 102400 (you will not want to use these settings)
- Cross-type AF points (holds the potential for higher AF precision)
- 6144-zone metering vs. 384-zone (more areas evaluated yields potential improvement in auto exposure results)
- Smart Controllers with half-press sensitivity for additional control
- 9.44 million dots, 0.90x EVF vs. 5.76 and 0.76x (bigger and better)
- Dual CFexpress type B memory card slots vs. CFexpress type B and SD (though some may prefer having an SD slot available)
- M.Fn3, WB, and second Info buttons
- Pre-continuous shooting (hindsight is far clearer than foresight, and recording an image of an action in the near past is game-changing)
- DIGIC X plus DIGIC Accelerator processors for exceptionally fast and intelligent AF and AE calculations
- IBIS provides up to 8.5 stops of shake correction vs 8 (while 8.5 is better than 8, the difference seems modest)
- Improved Eye Control AF (potentially a big deal if the R3's Eye Control was not compatible with your eye)
- Adjustable frame rates (30, 20, 15, 12, 10, 7.5, 5, 3, 2, and 1 fps)
- Full HD at 240p vs. 120p
- Pre-recording (3 or 5 seconds) (hindsight is far clearer than foresight)
- HDMI Type-A vs. Type-D
- Neural Network upscaling (2x larger in both dimensions to 179 megapixels) and noise reduction processing in camera
- 802.11ax Wi-Fi 6 GHz vs. 802.11ac (5 GHz)
- Longer battery life rating (1330 LCD and 700 EVF vs. 860 and 620)
Here are the R3's advantages:
- 4.15 million dot LCD vs. 2.1 million
- modestly smaller and lighter
- Lower price
If that last bullet did not exist, the easy choice would be the R1.
The last bullet is supported, and the R3 provides significant performance for its cost.
Still, the most demanding professionals will want the R1.