Olympus E-P1 High ISO NR
Olympus E-P1 Noise Reduction
The Olympus E-P1 offers 4 levels of noise-reduction settings giving you some flexibility in choosing how you want to make the trade-off between subject detail and noise levels. The E-P1 applies NR to its JPEGs at all ISOs, so we've included crops for all ISOs in the tables below. The combination of shooting with NR turned down to the lowest setting and using a good noise-filtering program after the fact can produce very clean images with lots of fine detail in them.
See for yourself how the noise reduction works under daylight-balanced lighting. Click on any of the crops below to see the corresponding full-sized image.
The above crops show the effects of the Olympus E-P1's four levels of noise reduction available, under the studio HMI lighting we use to simulate daylight. To our eyes, the default level of noise reduction strikes a good balance between noise and subtle subject detail, although the red fabric swatch presents a real challenge, as it does for virtually all cameras we test. Cranking the noise reduction setting up to High produces very smooth-looking images, while still maintaining good detail in areas of high local contrast (as seen in the circular scale), but a lot of detail is lost in areas of subtle contrast (the red fabric swatch is a particularly challenging subject, and the detail loss there is worse than you'd find in most real-world examples). At the other end of the scale, the Off noise reduction setting leaves a lot of noise in the image, but also leaves the subject detail largely undisturbed: Use this setting if you have good third-party noise reduction software; with appropriate processing, the result could be quite good. You should be able to do even better working from the RAW files.
But how does the Olympus E-P1 compare to other fairly compact models capable of shooting movies? See the following table which compares at the default Noise Reduction setting.
To our eyes, the Nikon D5000 has the best high ISO image quality of the group, however it's surprising just how good the Olympus E-P1, especially considering its compact size and smaller Four Thirds-format sensor. The Panasonic GH1 was a major step forward for Four Thirds-format high-ISO performance when it came out, and the E-P1 for the most part keeps up with it very well.
Detail in the red fabric swatch is lower for the E-P1 at ISO 800, but looking at the full images, the E-P1 does very well. Each camera obviously makes somewhat different trade-offs between noise and image detail, compounded by the number of different NR settings each offers. In our view, though, the Olympus E-P1 generally did better than the GH1 at high ISOs, although the two cameras were close competitors, and points could be argued either way in various situations.