How stable will Panasonic GH4 and the Pany/Leica 100 to 400 be?

6 X 17 Feind wrote:

My normal camera is a Nikon D-800 and my long lens is an older 300 f/2.8 without any kind of IS. I am aware of good long lens technique and I am an avid Monopod user. A recent outing to photograph critters showed me quite conclusively 300 ain't near enough lens and even a 1.4 teleconverter wasn't enough. The expense of going to a longer lens in this vein is extreme and my thought process was that a GH4 (fairly affordable these days) and the 100 to 400 would give way more versatility in this area. I am not a sensor size nut and M4/3 will produce very fine photographs of critters in general. Besides if I ever do get around to printing anything most animals photos aren't printed huge anyway.

One question: Why the GH4 and not the G85?  The G85 has a lot of advances over the GH4, and is about the same price now.  Or, if you want the more advanced sensor, the GX8 (what I use) is a fabulous combo with the 100-400mm, and price is going to be approximately in the same ballpark.

My reason for asking is any IS will be a step up and I am curious how much this new technology will help.

A LOT.  The OIS in this lens is really pretty darn remarkable.  You should very easily be able to go to speeds 1/focal length, and I routinely end up at 1/ half the focal length.  So, I can get sharp shots, with just the right conditions and body bracing, at 1/200 for 400mm.  (See shot below).  Of course, the more you push it, the more likely you are to end up with some blurry discards, but if you work on your technique, you can do wonders with the IS in this lens.

(These were both hand held).

-J