As a flagship sports and wildlife camera, the Olympus OM-D E-M1X relies heavily on its Micro Four Thirds sensor. While this smaller sensor format offers massive advantages for extending the reach of your telephoto lenses, the inherent physical trade-off is how it handles low-light situations and higher ISOs.
Unlike some full-frame bodies that feature eye-poppingly high ISOs into the six figures, the E-M1X has a fairly modest, practical range from 64 to 25,600. The native ISO range — the true sensitivity the hardware sensor is designed to handle — is 200 to 25,600. The two lowest settings (ISO 64 and 100) are part of the “Low” extended range, where the camera’s software takes over to pull the exposure down.
The original RAW files for the images in this post are available to subscribers to my newsletter on the RAW file downloads page. The page is password-protected; the password is in the newsletter’s welcome email. The JPG versions linked in the captions stay free.
About this ISO Test
To see exactly where the E-M1X’s sensor starts to show its limits, I shot a standardized test scene. While it isn’t the typical fast-action scene an M1X shooter might normally photograph, it provides a brutal test for the sensor. It features smooth gradients, deep shadows, sharp details, and subtle colors — the exact combination of elements that quickly reveals noise and color shifting.
Here is how the files below were processed:
- The Baseline: Each shot corresponds to a 1/3-stop step in the camera’s ISO range, shot originally in RAW (.orf).
- Zero In-Camera Smoothing: For JPEGs, the camera’s processing engine applies built-in noise reduction by default. To show you the true sensor performance, the images embedded on this page were regenerated in Lightroom directly from the RAW files with zero noise reduction applied.
- Download the Originals: Because there are still many situations where it makes sense to shoot JPEG, I’ve included links to download both the original straight-out-of-camera JPEG and the RAW file in the caption for each image.
Note: The RAW (.orf) files range from 18MB to 25MB, while the original JPEGs range from 6.5MB to 12MB.
ISO Range Sample Images: Olympus OM-D E-M1X
Click on any image to open a full-size version for a closer look, or use the links in the captions to download the original files to inspect on your own monitor.
Things worth knowing about the E-M1X
The Auto ISO limit
If you’re relying on the camera’s Auto ISO feature to manage exposure on the fly, it’s important to note that the camera caps Auto ISO at 6400. If you are shooting in extremely dark environments and need to push beyond that limit, you’ll need to manually dial in your ISO settings.
Taming MFT noise in post-processing
If you shoot heavily in the upper limits of the E-M1X’s ISO range, the noise profile of the Micro Four Thirds sensor can be aggressively managed in post-processing. Modern AI-driven noise reduction tools — such as Lightroom’s Denoise AI, DxO PureRAW, or Topaz Photo AI — can comfortably buy you an extra 2 stops of usable high-ISO range when applied to the E-M1X’s raw .orf files.
Hands-on review
You can dive deeper into the camera’s autofocus, ergonomics, and overall performance in my full hands-on review of the Olympus OM-D E-M1X here.
Where to buy the Olympus OM-D E-M1X
Because the E-M1X is an older flagship body, it represents an incredible value on the used market, though you can still occasionally find retail stock. You can check current pricing and availability at B&H Photo and Amazon.
Used:
