[_caw]

I own a pair of the 10x42s and they are indistinguishable from magic. When you press that button, the wobbly image becomes rock-solid and allows you to perceive and enjoy way more detail than would otherwise be possible.

Perfect for observing birds, planes, double stars, nebulae, satellites, and planets. I can't resolve Saturn's ring, but Jupiter and its moons and the Hercules cluster are not to be missed.

A tripod doesn't solve the same problem. You can walk around, pass these to other people, take it on a hike, use them in a car.

Some downsides: expensive, battery maintenance, and heavy (not as much a problem with smaller pairs.)

[rsync]

"When you press that button ..."

Why is there a button ? Why not just image stabilize at all times ?

I think perhaps it must be energetically expensive and therefore eats the batteries ?

If I am correct, then a follow-up that I didn't see answered in the OP: how long does the image stay stabilized after you press the button ? Can you turn it off or does it time out ?

[_caw]

You are correct, it eats battery; it lasts about 8 hours or so on li-ion. If you look down the lens and move it around, you can really see the mechanical movement in action.

It has two operating modes.

1, it stays on as long as the button is depressed. This is good for quick looks.

2, you press it once and it stays on until either (a) 5 minutes pass, or (b) you press it again, or (c) you put the binoculars down (it knows when they are vertical, like hanging around your neck.)

[i_am_proteus]

Image stabilization does indeed eat batteries.

[ComputerGuru]

I understood it needs to remain pressed.

[bookofjoe]

Not true. Press briefly and it stays in IS mode for a couple minutes.