Is the Sony A7r4 Noise Performance Worse than the Sony A7r3?
A brief post as Sony A7r4 test images start to come out. I intend to do my own testing when I get my hands on a Sony A7r4.
Imaging-resource added studio test scenes with the Sony A7r4 recently. My first impression was that it was a bit noisier than the Sony A7r3. On a pixel level, it’s not surprising: Higher resolution cameras are noisier on a pixel level, as you are effectively enlarging the image more as resolution increases. You end up looking more closely at smaller pixels. Typically, if you equalize the size when comparing cameras of different resolutions, by downsizing the higher resolution image, you squash the noise. For example, if you pixel peep the Sony A7riii and Sony A7iii, the Sony A7riii looks noisier. But if you downsize the Sony A7riii to the same size as the Sony A7iii, the noise evens out. This is captured in the DXOMark comparison:
Imaging-resource doesn’t equalize the print sizes, so it was difficult to judge whether the Sony A7riv images were really truly noisier.
Dpreview just printed their test scene for the Sony A7riv. So thanks to Dpreview for providing this resource, of which I snipped a few captures for demonstration. Dpreview allows for side by side comparison of multiple cameras with equalized image size.
Before getting there, let’s briefly talk about image size. I previously posted, questioning the degree of benefit we really get from 61mp versus 42mp. I argued that the resolution gain of 61mp would be insignificant for most 42mp sensor owners, providing just slightly improvements in print size and cropping. Now we can see exactly the different between 61mp and 42mp and 24mp, throwing in the 32mp of the Canon R as well. Below, we see 100% cropping of each resolution:
As we go from the 24mp of the Sony A7iii all the way to the 61mp of the Sony A7riv, the different is pretty significant. But the difference between the Sony A7riii and Sony A7riv is pretty minor in my opinion.
Now, let’s start looking at what happens to noise at high ISO raw files:
The Sony A7riv is clearly the noisiest of the four cameras, but it’s also the most enlarged image. What happens when we downsize all the cameras to the equivalent of the Sony A7iii?
They are all now pretty close. To my eye, the Canon R looks the worst. The Sony A7iii and Sony A7riii look about the same. But the Sony A7riv looks a bit worse than the other two Sony cameras, especially with color noise in the blacks.
In the gallery below, I ran the test in a darker area of the test scene, with ISO ranging upward, to see the differences as we increase ISO (click to cycle through):
Some preliminary conclusions pending my own testing and confirmation:
- At ISO 6400, all 3 Sony cameras look good, they are all slightly better than the Canon R, which is starting to show noise
- At ISO 12,800, the Sony A7riv starts to show a bit more noise than the A7riii and A7iii, but not as bad as the Canon R. Differences are minor.
- At ISO 25,600-51,200, the Sony A7riv looks much worse than the Sony A7riii and Sony A7iii, though still not as bad as the Canon R.
- At maximum ISO, 102,000, the Sony A7riv looks really bad, just as bad as the Canon R. While the Sony A7riii and Sony A7iii looks better.
What Does it Mean for the User?
These noise differences at high ISO are truly not that significant. But it appears the user or prospective buyer should be aware that the high ISO image quality on the Sony A7riv may be a small step below the A7riii and Sony A7iii. At the same time, the gain in resolution from 42mp to 61mp is also realistically only a small step, in practicality. So you are possibly trading a small loss in high ISO image quality for a small gain in resolution.
If you routinely shoot at high ISO (over 12,800), then you might not want to upgrade to the Sony A7riv solely for the resolution. (Though you may have other reasons for wanting to upgrade). If you mostly shoot at lower ISO, then you are likely to appreciate the higher resolution without any image quality downside.
This comparison, in my opinion, especially makes the Sony A7riii a bargain right now. As of September 2019, the regular price of the Sony A7riii is under $2,500. (See Sony A7riii on Amazon). As part of a bundle, Amazon has the Sony A7riii for under $2,400. Similarly, Amazon has Sony A7iii bundles for under $1,800.
I’ll test the Sony A7riv in the coming weeks or months myself. Right now, I wish we could get the Sony A7riii sensor with the other Sony A7riv upgrades. You can see or buy the Sony A7riv on Amazon.
