Fully aware that "the grass is always greener on the other side of the road", there are some features on this new concept camera that I just plain want. And this is in spite of the fact that I already own the much acclaimed Panasonic GH2; arguably, at least until now, the king of the hill for m4/3 camera bodies.
Here are the three features I want most:
This is not a bird. It stands for In-Body Image Stabilization. Panasonic, Canon and Nikon have their image stabilization system in the lens... but not all lenses have it. Olympus, Sony, and Pentax have it in the body. The advantage of IBIS is that when you upgrade your camera body, you instantly upgrade the stabilization of all your lenses. And because with a Nikon-to-m4/3 lens adapter I can use all my old Nikon lenses (one of which was produced about 1965), these lenses, too, are stabilized.
This is a huge advantage for me, as the Panasonic GH2 which I so enjoy has no IBIS. And since I have no Panasonic m4/3 lenses, none of my lenses are stabilized. In reality this has not been a huge problem since I can usually shoot at fast enough shutter speeds to eliminate camera (hand-shake) blur.
On the other hand, IBIS will help me in low light situations and for macro photography. This is especially important to me because I prefer not to use a tripod.
And finally, the new IBIS system in the E-M5 has 5-axis stabilization. Wow! Instead of the stabilization operating only in "up" and "down" directions, Olympus has added "pitch", "roll" and "yaw". Sounds excellent, huh?
The add-on grip (still on pre-order0 makes the camera a bit bigger. But I prefer that. It will allow the pinky of my right hand to aid me in holding the camera, plus give a substantial advantage when holding the camera vertically. At least this is how the battery grip on the Olympus E-620 worked for me. Without the extra grip, I know from my macro shots that I see a lot more hand movement through the viewfinder when I hold the camera vertically.
Auto ISO in Manual Mode
This may seem like a strange feature to list in my top three. But I have always enjoyed using it on my Olympus dSLRs and am pleased that it is included on the E-M5. I can't imagine why auto ISO is disabled on the GH2 when you are in the manual exposure mode; after all it is available on the lesser LX5.
I will use this setting especially when shooting wildlife and flowers. Here's how I use it for butterflies, for example. Set the camera at F8 for reasonable depth of field and 1/250th second shutter speed to stop action including any antennae vibration. Now as I move around the butterfly causing exposure to change depending on my angle to the light source, the camera will give me automatic and accurate exposures by adjusting the ISO accordingly.
With the known complexity of the Olympus menu system, and reports of a terrible user manual, I expect a couple of long nights coming up as I work through all the setting to get it set the way I want it.