Image Stabilization

To test the E-M5 II's image stabilization we've tried shooting a series of focal lengths using increasingly long shutter speeds. Each shutter speed was shot ten times: once with IS on (Auto) and again with IS off. The images were then assessed to the following standard:

Excellent Some softness
Noticeable blur Unusable

1) Excellent - the best the camera is capable of
2) Some softness - only distingusihable from Excellent by comparison
3) Noticeable blur - blur can be perceived without reference to another image
4) Unusable - significant motion perceptable

24mm Equivalent
50mm Equivalent
200mm Equivalent
Stablization On Stablization On Stablization On
Stablization Off Stablization Off Stablization Off

The E-M5 II's stabilization is sufficienctly effective that the 2.7EV range we tested it across isn't always enough to show the point where both IS On and IS Off become ineffective. However it is sufficient to show the difference in effectiveness at different focal lengths.

At 24mm equivalent, the success rate at 0.6 of a second with IS On is identical to that at 1/8th of a second with IS Off. This is a 2.3EV benefit, which is a very solid result. The pattern is similar at 50mm equivalent, with IS offering at least 2.3EV of benefit. This includes the camera getting 50% useable shots at 1/4sec (3.3EV lower than the 1/effective focal length rule would lead you to use).

Finally, and most impressively, at 200mm equivalent, it's almost impossible to get steady shots at 1/25th of a second (3EV below 1/effective focal length), and yet it was almost impossible not to get a stready shot with stabilization turned on. These results are broadly consistent with our assumption that with short focal lengths, exposure times can become so long that the stabilization system can't possible compensate for user movement, while with longer focal lengths, the IS system is extremely effective much further below 1/eFL.

You'll note that none of these figures comes close to the '5EV' rating confered from CIPA standard testing. We suspect that, just like CIPA battery life ratings, its stabilization figures don't necessarily tell you the result you'll see but instead give you a figure that can be sensibly compared between cameras and lenses. In other words, a '5EV' rated product probably won't give you a five stop improvement in stability but will give a better result than a 4.5EV-rated rival.

Movie stabilization

The thing that's most impressed us about the E-M5 II's stabilization is how capable it is during movie shooting. As you can see on the first page of this review, we were able to produce a video that intercuts between handheld and tripod-mounted footage without any significant change in stability. The only significantly shaken footage came from strapping the camera to a mountain biker's chest (something we didn't seriously expect to produce useable results).

This impressive stability overcomes our concerns about the camera's less-than-cutting-edge video quality, since it makes it so much easier to start shooting video in almost any situation. Our only major concern is that the movie mode: unlike stills mode, doesn't offer any way to choose which axes the stabilization works in. This means that, if you try to pan with the camera, the IS system will initially try to resist the movement, resulting in slightly jerky footage.

Furthermore, it appears to us that this effect may be slightly stronger when sensor-shift and digital image stabilization are combined, leading us to believe that it's due to interaction of rolling shutter and the digital aspect of the image stabilization system. The effect appears to be reduced if stabilization is set to 'sensor-shift only' mode (M-IS 2), so we'd recommend this in situations where there's likely to be a lot of fast movement.