Phase detect AF strips showing up in Olympus E-M1 video



Ever wondered if those sensor AF pixels or “sensels” can show up in your images?

I’m just fresh from shooting a music video with the Olympus OM-D E-M1. I love this camera for professional video. Really love it… The 5 axis stabiliser is unique on the market and no other interchangeable lens camera can do what the E-M5 can do with Micro Four Thirds lens, that stabiliser and no rig, even a tripod.

It’s unfortunate however in that the camera has a very unusual bug…

The E-M1’s new sensor includes phase detect AF strips which work very well, giving the camera the best AF system on any mirrorless camera and in any live-view mode around (in my experience).

It has a drawback however, when the lens is flared, these AF ‘sensel’ strips can show up on the image as I found in the frame grab above from my video.

These strips are surprisingly large and visible to the naked eye on the sensor.

For reference here is the Olympus OM-D E-M5 sensor. No phase detect AF strips on this sensor…


I call on Olympus to fix this if possible of course.

Even more of a priority is to get 24p in this camera at 50Mbit/s.

It should be a trivial firmware update.

If this was a pointless camera for video I wouldn’t care and would not be writing this article. It is not. The E-M1 is a unique camera featuring video quality which actually can stand up very well to professional cinema cameras like the Sony FS700.

But because of that stabilisation system I can go out there with no rig, shoot something handheld with a beautiful fast prime without OIS of my choosing – absolute freedom – no shake, no jitter, then do an instant punch-in crop of part of the frame in the middle of a shot! It is so convenient to shoot this way.

You won’t believe how liberating it is. To leave that tripod at home, leave the matte box and the rig, leave all that crap at home and just go and shoot.

Olympus do not realise what they have here! How valuable this is to video people!

For this convenience and artistic freedom I’d happily take a drop in image quality from the very best, drop my raw shooting 5D Mark III, leave the Sony FS100 on the shelf and keep the Canon C300 at the rental shop.

But PLEASE Olympus fix the bugs and give us the filmic frame rates of 24p (25p for Europe) and a higher bitrate. You will get tons more sales from the professional video community if you did this simple change.

As for the phase detect AF showing up on the image… I’ll allow you to have your say on why this could be and whether it could be fixed. On the vast majority of shots they never show up. It only seems to be a problem when pointed directly into the light.

I have not shot stills with the camera yet so I don’t know if it will affect those too, or just video. I expect it will affect stills just the same.