Noise and DR roundup for Sony A9 and EM1x
If you would rather head straight to a concise summary, the TL;DR is at the foot of the page — or jump directly to the FAQ.
Many Olympus owners cannot accept that the noise and DR (dynamic range) of an EM1x camera can often be comparable to an A9. It seems to run counter to their own direct experience with their cameras. In this post I want to show how their experience and my data can both be correct.
TL;DR
- EM1x and A9 noise performance are comparable at equivalent focal length and aperture—not sensor size, but lens speed and design that matter for real-world SNR.
- A9 has 1–2 stops more dynamic range at base ISO, but that gap shrinks to near-parity at ISO 3200+, where BIF shooting occurs.
- Why Olympus owners see worse noise: they’re often comparing to full-frame owners using faster lenses (300mm f/2.8 vs Olympus 100mm f/2)—not equivalent systems.
- When systems are matched for reach and aperture, EM1x beats or matches A9 in noise due to superior lens design and 5-stop IBIS.
- For birds in flight, noise is manageable on both systems; focus accuracy and AF reliability matter more than sensor specs.
Frequently asked questions
How can the EM1x match the A9 in noise if it has a smaller sensor?
Signal-to-noise ratio depends on photons collected per pixel, not sensor size. EM1x 100mm f/2 collects more light per pixel than A9 300mm f/4 at 2× magnification. Add 5-stop IBIS (allowing faster shutter speeds), and the EM1x often wins on real-world SNR.
Do the DR differences matter for birds in flight?
At base ISO (where A9 has 1–2 stop advantage), you rarely shoot BIF. At ISO 3200–6400, the DR gap is negligible. Highlight recovery matters more than shadow detail in BIF work—both systems handle this equally.
Why do full-frame owners say their images look cleaner?
They’re usually comparing A9 (300mm f/2.8) to EM1x (100mm f/2). The Sony lens is actually faster equivalent and collects more light. That advantage has nothing to do with sensor size—it’s lens design. At matched apertures, the EM1x frequently looks cleaner.
What’s the practical impact of EM1x vs A9 noise for portfolio work?
Negligible in output at 24-megapixel print size. A9’s output has slightly less visible banding in extreme shadows. EM1x’s detail retention is superior due to in-camera processing. Both require denoising at ISO 6400+; results are comparable after DxO or Topaz.
Should I choose between them based on noise specs alone?
No. Choose based on: (1) AF performance (EM1x cross-type wins), (2) system weight (EM1x wins), (3) lens ecosystem (Sony has more options), (4) budget. Noise is comparable enough that it shouldn’t be a tiebreaker.
