Multi-lens speed and noise comparison of EM1x to Sony A9
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.
In this post I make a lens speed and noise comparison between the EM1x and the A9 across the whole range of lenses that a professional or high-level amateur might use, including matched pairs of images from each camera at a range of ISO levels so that you can see for yourself what the differences are.
TL;DR
- Matched lens speeds (e.g., EM1x 100mm f/2 vs A9 200mm f/2.8): EM1x noise is equal to or better than A9 at all ISO levels up to 6400.
- At practical telephoto speeds for BIF (EM1x 100mm f/2 vs A9 300mm f/4): EM1x wins on signal-to-noise ratio due to superior lens speed.
- At ISO 3200+, noise differences are perceptually negligible after standard denoising in both cameras.
- EM1x’s 5-stop IBIS allows lower ISO at equivalent shutter speed, further narrowing apparent noise margins.
- Choice between systems should favour AF, ergonomics, and lens ecosystem—not noise, which is comparable in real-world BIF use.
Frequently asked questions
Why does noise matter for bird photography?
High ISOs are inevitable at 1/2500s shutter speed on overcast days. Cleaner shadows allow more post-processing flexibility and better shadow detail in underexposed landing sequences.
How is SNR calculated in this comparison?
Matched focal length and aperture (e.g., EM1x 100mm f/2 produces 4× magnification and f/4 effective; A9 400mm f/8 produces same magnification and aperture). Light collected per pixel is identical; noise differences reflect sensor and lens design only.
Does the A9’s larger sensor always win?
No. Larger pixels collect more absolute photons, but matched apertures and magnification equalize this advantage. Lens optics, sensor quality, and in-camera processing matter equally.
How does IBIS affect noise perception?
EM1x’s 5-stop IBIS allows shooting at ISO 1600 at the same shutter speed where A9 requires ISO 3200 (no IBIS). That’s a 1-stop SNR advantage for the EM1x independent of sensor performance.
Is real-world noise difference perceptible in prints?
At 24-inch print size (typical portfolio), no. Both systems exhibit fine grain at ISO 3200+; artefacts are only visible on screen at 100% zoom. For client delivery, differences are immaterial.
