4. IMAGE QUALITY: ISO, RESOLUTION, DYNAMIC RANGE.
My M43 using friends have always been full of how great the format is. And I have agreed that they have taken excellent images with their cameras, but I have always felt that the image quality has lacked a little compared with current SLRs. This is not a good and bad situation. It was always a good and better one. To my eye SLRs were better at high ISO, were more subtly in colour transitions and were better at coping with extremes in dynamic range. The key word in that sentence is “were”.
The E-45 has made a big, big step in M43 image quality, vaulting it right into the ranks of the SLRs. My feeling for underwater images is that it produces overall better image quality than a Nikon D300 or Canon 7D and is a close match to the Nikon D7000. DxO Mark are yet to test it, I will be very interested in what results come out.
RESOLUTION The E-M5 boasts 16MP and is very sharp at a pixel level. This is the same resolution as the D7000, two less than the 7D and D60 and 4 more than the D300. Given how good the files look at a pixel level, it is hard not to conclude that this resolution is not sufficient for almost every use.
ISO High ISO performance is the area where I feel the E-M5 most demonstrably impresses, for me it is clearly ahead of the D300 or 7D. Viewing the RAW files at 100% at ISOs 200 and 400 shows no significant noise, ISO 800 has only a very minor noise level, ISO 1600 the noise is visible but still not especially intrusive and at ISO 3200 the noise is clear, but the file remains entirely useable. Such performance from 16MP of tiny pixels left me stunned.
A sequence of four flash lit wide angle shots of a diver inside a cave, with the 8mm fisheye taken at ISO 400, 800, 1600 and 3200.
These are 100% crops of the 16MP RAW file with NO noise reduction in post processing. The slight difference in the size of the diver is because of small changes in camera to subject distances. Shot at ISO 400, 800, 1600 and 3200.
When noise reduction is applied the ISO performance is even more impressive as the type of noise is easily controlled by processing software. Even images taken at ISO 6400 are perfect for online use in electronic publications or for small prints.
Above are two images and two 100% crops from images taken at ISO 3200 and 6400. In this case I have applied a low amount of noise reduction in Lightroom 4. The image quality of the files is very impressive, even at ISO 6400 you can clearly read the brand of drysuit.
I found dynamic range harder to evaluate. I certainly didn’t rate it as anything less than good, but the conditions and lack of time made it difficult to rank it even subjectively against the SLRs. My gut feeling is that it is close, but slightly behind. But I would like to perform more tests to be sure.
Anyone coming from an existing compact or M43 is likely to be very impressed. Those considering a switch from a SLR will also not feel they are giving much away in dynamic range.
In conclusion, the image quality from the E-M5 is excellent and the high ISO performance is particularly impressive. The quality is such that I cannot see the sensor being the limiting factor in what this camera can be used for.
- Olympus OM-D E-M5 camera and specs.
- The Olympus housing and underwater handling.
- Image quality: ISO, resolution, dynamic range.
- Lens performance, autofocus & stabiliser.