I think this has been discussed before but I couldn’t find it, maybe it was on the other site. I just got a Canon RF 100mm macro, and I couldn’t remember if image stabilization was recommended for underwater macro stills?

I've never ask me this question. Since the begining I take the photo with image stabilisation..

It probably bring nothing good or bad... when you take a macro you are stable

Image stabilisation would be handy if you are relying on available light (no strobe).

But if strobes are your primary light source, the short duration of their flash should freeze the subject OK, even if you yourself are wobbling about!

And don't forget, image stabilisation only helps reduce your shakes, not subject movement...

That's a good question for macro where sharpness is critical.

A long while ago when I was using some of the initial Canon IS lenses with land camera (such as 24-105L IS), the IS was quite effective for handheld/slower shutter in situations like available light street portraits, however I would still feel the old IS "buzzing" into the lens. On a fast shutter speed it was no benefit and to an extent, some photographers would say it could be a nuisance to the sharpness as the optic groups would slightly move. I could also experience that on some of the still images I was shooting at that time : sharpness but not ultra sharpness as expected when the IS was on.

IS has certainly progressed since, I have now a RF100 IS that I use for most of my UW macro shots but I must admit I never wondered about switching the IS off. TBH with the hindsight, ie. using a fast shutter like 1/200s with the strobelight freezing the subject for some ms., add on top that the density of water environment don't allow fast shake movement, I don't see what would be the benefit of the IS in these conditions. On the contrary I can only guess the inconvenience of using more battery life and maybe some residual slight internal "shaking" (certainly at a lesser level than 20 years ago).

Hence probably something to think about when not using continuous lighting and slower shutter.

Edited April 26Apr 26 by Luko

1 hour ago, Luko said:

On the contrary I can only guess the inconvenience of using more battery life

Probably, but how big is the difference?

I'll try swichting the IS off for some dives during ma next trip.

I think IS has a number of uses, the obvious one being hand holding assistance. AN additional consideration is stabilizing against movement from surge or current - I find it seems to help keeping the AF point over the subject. It's a common issue on Sydney dive sites that are subject to surge on occasions. I certainly notice it on land based hand held macro shots and it helps keep the AF point just where I want it.

I thought I remembered reading somewhere that your motion in the water was different than motion in the air, so IS was compensating in the wrong way?

Also, I need to figure out how to only turn IS on when my finger is on the shutter. With the R5 EVF, it’s moving constantly. I’m used to IS on my 70-200 telephoto on the 5D4, it would only switch on when you needed it.

10 hours ago, jlaity said:

I thought I remembered reading somewhere that your motion in the water was different than motion in the air, so IS was compensating in the wrong way?

Also, I need to figure out how to only turn IS on when my finger is on the shutter. With the R5 EVF, it’s moving constantly. I’m used to IS on my 70-200 telephoto on the 5D4, it would only switch on when you needed it.

Seems unlikley, the IS system only responds and cancels out whatever movements it detects, if the movements are slower it only makes its job easier. There were reports on the first generation IS that it didn't work well at high shutter speeds on long telephoto lenses, but I think it has moved beyond that now. I just leave IS on all the time, it activates on a half press of the shutter on my system.

On 4/26/2025 at 12:06 AM, dentrock said:

Image stabilisation would be handy if you are relying on available light (no strobe).

But if strobes are your primary light source, the short duration of their flash should freeze the subject OK, even if you yourself are wobbling about!

And don't forget, image stabilisation only helps reduce your shakes, not subject movement...

Exactly right.

Yes, when using strobes for light I suppose it doesn't matter. Unless I'm opening the shutter for more blue, but that's usually going to be a longer exposure than IS can handle.

On 4/26/2025 at 7:36 PM, Luko said:

On a fast shutter speed it was no benefit and to an extent, some photographers would say it could be a nuisance to the sharpness as the optic groups would slightly move. I could also experience that on some of the still images I was shooting at that time : sharpness but not ultra sharpness as expected when the IS was on.

I haven't noticed any downside to leaving IS on all the time, above or under water (Sony system).

Some bird photographers say you should turn IS off if using a big tele on a tripod. A comparable UW scenario might be using a 90-100 macro for close-ups on a tripod, but that's a pretty extreme example. If that's you, try it and see!

I think I also read somewhere that IS only works in two dimensions (side to side / up and down, but not back and forth). If so, Chris' comment about being shaken back and forth in a surge might be an example when IS wouldn't help (if you needed it). But presumably, still no probs leaving it on...

The benefit is largely around slowing down the movement of the AF point from target so the AF can lock on, it doesn't work miracles but I find it helpful. Basically the AF is your third axis to counter back and forth movement. I see no reason to turn it off, some of the earlier generations might have caused some issues, but today it is sound technology.