The D500 (which I still have and my wife uses) works fine with the batteries for the recently introduced Nikon Z8. So not a problem in this case at the present time.

There are many potential causes of vibration even when using a tripod which could benefit from the image stabilization of a lens and camera being on, including the movements of the shutter, wind moving the lens, your pressing the shutter button, etc However in the "early days" of image stabilization one could see that turning off this system would result in a sharper photo (I actually did some tests a number of years ago and saw this) when the unit was on a tripod. However with the newer image stabilization systems this is not very common.

oops duplicate post

Wow, can even see a solar flare!

I have wondered if wildlife photographers (ie. those using big lenses) have a higher incidence of back injuries (ie. surgeries). Anyone know of any studies and/or statistics?

Not sure how heavy your lens is, but each of us has our limits in the amount of weight we can readily carry when hiking and hold up to photograph. But for most "heavy" lenses, it is best to get a strap that attaches to the "foot" of the lens versus attaching a strap to the body mount. One can relieve the stress on one's neck by using a strap that goes across the body, like the Black Rapid Strap, attached to the foot of the lens while it is attached to the camera body. That way one can rapidly move the camera up into shooting position when one sees a bird that they want to photograph (hopefully your lens has a foot, if not, you can probably find one to purchase).

Yep, but considering that this is a path in a public park, there were lots of walkers who would be passing by as well.

Since I almost only photograph wildlife, the last point is the most important one to me. Just this week I was trying to photograph a kingfish, a Northern flicker and a river otter. Each of them were incredibly sensitive to my location. Anytime I got closer than 20 feet or so, even though I was very slowly approaching, they would take off. So for wildlife photography (as others including you note), high megapixel cameras and a high focal length lens are essential (much to the dismay of my knee and back).

A 500mm PF is quite a bit lighter and focusses faster plus works better with a TC (yes I own both). You can probably pick up a used one these days for a decent price. Unless you think you might need to zoom our to get something close much of the time, why not get a prime? I usually end up cropping anyway for wildlife, especially birds. Just a thought.

Thanks, want a lighter lens and don't really think that I would shoot at 600mm. Plus prefer having the 100mm at the low end (ie. 200mm 35mm equivalent). So was hoping for an updated version of the 100-400mm which had image stabilization that worked with the camera or better low light abilities (ie. wider aperture). Not a longer FL. Will wait, maybe their next lens will fit better what I am looking for.

PS. For my video I shoot at slower shutter speeds, 1/50 or so.

Thanks, that was my understanding as well. Have you tried to do handheld video at 400mm focal length with this lens?

Not sure what you mean that the OM 100-400mm lens IS works "in conjunction" with the camera body IS but according to the Olympus website: "5-Axis Sync IS is not supported in the 100-400mm lens." The camera system is expected to use either the in-body 5-axis stabilization system or the 2-axis (yaw and pitch) image stabilization in this lens, which provides 3 steps. By contrast, the Olympus 300 mm f/4 lens provides 6 shutter speed steps of compensation with its 5-Axis Sync, lens and body. So to me, that means they don't work in conjunction.

Thanks, you are right, it is close and have been tempted! But for $7,500, would want something closer to my dream lens. Since I already have lots of lenses, I can wait. Maybe someone at OM Systems is monitoring these discussions.
PS. The real weight of this lens with its hood and foot I believe is over 4.5 pounds. Think the weight you have is without the hood?

If you want to argue or quibble semantics, I am out. But a f/4 on a micro 4/3 sensor gives a DOF of an f/8 lens on a full frame sensor, I am sure you know this. So if you are trying to isolate a subject and have comparable bokeh, then you need to use a f/2.8 lens on the micro 4/3 sensor to make it comparable to the f/4 on a full frame sensor. And an f/4 on a full frame sensor collects 4 times as much light as on the micro 4/3 sensor. So yes the focal length and aperture are integral parts of the design of the lens, but the size of the sensor affects things (it drove me crazy when I went on a photo tour with several OM users they would call their 300mm lens a 600mm lens). So just as an f/4 is an f/4 no matter what camera you put it on, the 600mm is 600mm. If a 300mm f/4 OM lens on a micro 4/3 sensor was really the equivalent of a 600mm f/4 lens on a full frame sensor, all those Sony, Nikon and Canon photographers are wasting their money and struggling with the increased weight for no reason? And based on your arguments, why not just use a camera with a 1 inch sensor like the Sony RX10? That would save even more weight.
PS. I have seen lots of great photos taken with the OM system and some day I might even switch to it, so this is not meant to "trash" the system. I would love it if OM systems would bring out a light weight zoom lens which had the IS of the newer lenses as well potentially better aperture, say a 100-400mm f/4.5 without the built in TC with 7 stops of IS. And my wish would be that it would be under 4 pounds.