Sony A7S II Image Quality

As expected, the Sony A7S II produces in-camera JPEGs that are very similar to its predecessor at base ISO in terms of noise and detail, however we do see the difficult red-leaf fabric is rendered slightly better by the A7S. This is likely related to the slightly lower color sensitivity scores reported by DxOMark for the newer model.

Again, very similar image quality at ISO 1600, but we continue to see the A7S do a little better than the A7S II in our tricky red-leaf fabric.

Once again, it's the older model with a slight edge in the red-leaf fabric, but both do extremely well at this sensitivity.

Comparing A7S II and A7S converted raw files at base ISO with no noise reduction or sharpening applied shows results similar to what we saw with the in-camera JPEGs: Almost identical images in terms of detail and noise, but the A7S does slightly better with our tricky red-leaf fabric with higher contrast and lower noise, while rendering some colors slightly differently as well.

Here we're comparing the 12-megapixel A7S II to its latest 24-megapixel sibling, the Sony A7 II, resampled down to 12 megapixels. As you can see, even after being converted to 12-megapixels, the A7 II renders fine detail noticeably better than the A7S II with better sharpness, but moiré patterns are evident in the red-leaf fabric. However, if you click on the crops and view the full target, you'll see it's the A7S II's image that has more aliasing artifacts in the form of color moiré in the Pure Brewed label. This is mostly because the distances and frequencies involved are such that moiré happens to generated from the finer thread pattern in the red-leaf fabric by the higher resolution A7 II, while the A7S II generates it from detail repeating at a lower frequency in the Pure Brewed label. Bottom line, though, the A7 II produces better detail and just slightly higher noise levels at base ISO when normalized like this. And keep in mind the A7S II's images will require additional sharpening to match the sharpness from the A7 II, which will increase the appearance of noise. (You can view the A7 II's full-res version by clicking here.)

In this comparison, we pit the 42-megapixel Sony A7R II normalized to the same image size against the A7S II. As expected, we see much better detail and crispness from the much higher-resolution A7R II which has no AA filter, though again, it generated moiré patterns in the red-leaf fabric as well as in the Samuel Smith logo (click the crops to see the entire target). Noise is a bit higher from the A7R II, but it's still quite low at base ISO and keep in mind: a) the A7S II requires sharpening to match the A7R II's sharpness which exacerbates noise and b) the added detail from the A7R II will allow you to get away with stronger noise reduction before impacting detail to the point where the A7S II's detail is better. (You can view the A7R II's full-res version by clicking here.)

It's a similar story compared to the AA-filterless 36-megapixel Nikon D810. Again, better detail from the higher-resolution camera even after resampling, but with aliasing in the red-leaf fabric and bottle labels. This time, though, noise levels are quite comparable. (View the D810's full-res version by clicking here.)

Here's a comparison with the highest-resolution full-frame DSLR currently available, the AA-filterless 50-megapixel 5DS R. Again we see stronger, crisper detail from the resampled 5DS R image, but with aliasing artifacts in the red-leaf pattern and Samuel Smith label. Noise levels are however noticeably higher from the Canon, but again, keep in mind the difference in sharpness and detail. (View the 5DS R's full-res version by clicking here.)

As expected, at ISO 6400, the A7S II and A7S produce practically identical results with minor differences limited to color response.

Here at ISO 6400, we immediately see the A7S II has much less noise than the A7 II, but as expected, detail and sharpness are better from the A7 II, though moiré is still visible in the red-leaf swatch. (View the A7 II's full-res version by clicking here.)

Again, the A7S II produces lower noise levels at ISO 6400 but the A7R II is sharper with noticeably more detail, though moiré patterns are still visible. (You can view the A7R II's full-res version by clicking here.)

It's a very similar story with the D810, with higher noise but finer, crisper detail. Again, as we've seen from all the high-resolution cameras in the comparison, moiré patterns are quite evident in the red-leaf swatch. (View the D810's full-res version by clicking here.)

The Canon 5DS R isn't known for its high ISO performance, so it's no surprise noise is still significantly higher after being resampled down to 12 megapixels, however fine detail and sharpness is better. Again, we see some moiré patterns in the red-leaf swatch from the much higher-resolution Canon. (View the 5DS R's full-res version by clicking here.)

Once again, as expected the two 12-megapixel siblings produced nearly identical results at ISO 12800 except for minor differences in color and the red-leaf fabric.

The A7S II still produces lower noise at ISO 12800, but this time the higher noise from the A7 II interferes with detail to the point of making the A7S II the better performer at this sensitivity even with the A7 II resized down to 12 megapixels. (View the A7 II's full-res version by clicking here.)

This is a very interesting comparison. The Sony A7R II is definitely noisier, but not by a whole lot when normalized. And it continues to produce a sharper image with better detail, so in the end which one would produce a better image after noise reduction is applied will likely depend more on your software and workflow than which camera. For example, when using one of our favorite raw converters (DxO Optics Pro 10 with PRIME noise reduction) to convert ISO 12800 .ARW files from both cameras using the same default settings, we found the resized A7R II image contained noise levels very similar to the A7S II's, yet contained noticeably better detail. (You can view the A7R II's full-res version by clicking here.)

It's a similar story compared to the Nikon D810 at ISO 12800: Lower noise, but less detail. After running both through DxO Optics Pro with PRIME noise reduction, the A7S II still came out ahead in terms of noise, but only slightly, while the D810 still managed better detail. (View the D810's full-res version by clicking here.)

Noise levels are much higher from the Canon 5DS R at its extended high ISO limit, but its much higher resolution helps when images are normalized, and it does retain better detail. The A7S still comes out ahead overall at ISO 12800, but who'd have thought the 5DS R which isn't considered a great high ISO performer could even come close to the low-light champ when normalized. After the same treatment in DxO Optics Pro with PRIME NR, noise levels are just a bit higher from the Canon, but detail is also generally better, except in the red-leaf fabric. Be aware, though, that ISO 12800 is the Canon's top extended ISO whereas the A7S II tops out at a native ISO of 102,400 and an astronomical extended ISO of 409,600. (View the 5DS R's full-res version by clicking here.)

All this to say that significantly higher resolution full-frame cameras can give the Sony A7S II a run for the money when normalized down to the same 12-megapixel resolution. So if you need more resolution than the A7S II offers at lower ISOs yet still want great high ISO performance and are willing to work with resized converted raw files, a much higher resolution camera may make more sense allowing you to tradeoff resolution for high ISO performance.