a6k Loc: Detroit & Sanibel

This is NOT about using the camera on a tripod.

This is about using IS at high shutter speeds. In my case, I use high speeds because birds rarely hold still. So I use shutter priority as my primary setting.

This screen shot is the same target at the same time (a few seconds apart) at 1/1000 sec. The left side is IS=off and the right side is IS=on. Both were fine-focused using DMF (Sony's terminology). The camera is my RX10m3. The "view" is "actual" and then two zoom-in clicks on each side. The ovals are where I was aiming and focusing.

In my opinion, the left side is sharper because it lacks the ghost image which I strongly suspect is an artifact of the IS.

Of course, it's harder to use the camera with IS off when it's zoomed to the max, which these were.

I did this experiment because I was seeing results while shooting that had differences in sharpness when they were taken with identical technique of same subject, same time (plus a few seconds). Yes, I know I'm being very picky. However, this camera is simply not as sharp as it's more expensive sibling, the a7R II and the lens, while very good, probably is not the equal of a G-master. So I don't want to give up sharpness that I can have for free!

Please feel free to educate me about this. I've already reviewed a lot of posts about the subject but still don't fully understand what is going on.

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SS319

IS will minimize camera shake, it will not control subject motion. It appears from the back branch that you had wind or other subject motion - could that be what you are seeing between your shots.

I suggest you set up and use a suitable camera target that is stationary, use a tripod to eliminate one variable and take the pictures with the two systems of interest.

Now you can take the camera off the tripod and compare results.

Unless you limit the variables(Camera Motion, Subject motion, camera settings) in each test shot to only one, you will never discover the real problem.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

I think there is no movement in either image. The "ghost" on the twigs is on both sides. What you might be seeing is focus acquisition while the shutter is open. Try one more test - use back button focus (or whatever you need to do to disable focusing on half press), then take the two test shots, with and without IS enabled and with out active focusing going on. I suspect your results may be different.

IS conflicting with high shutter speeds would look like movement, but it may not be across the entire image, since the shutter travels as a slit across the sensor, and the reaction time for IS to work could be shorter than the exposure time. I have nothing other than an opinion on this, and the fact that I get exactly the same effect when I have autofocus active while tracking a moving subject, or if focusing on a static, low contrast subject when focus is constantly reacquiring. I found that focusing on demand, as I do with the back button, helps minimize the effect.

a6k Loc: Detroit & Sanibel

I will study this further but please note I use the electronic shutter so the assumed effect of the curtain should not be in play here.

stillducky

I shoot a lot of birds too, nikon d500 with a nikon 200-500 lens and I always have IS turned on handheld. I can actually sometimes see my focus point vibrate when trying to focus at 500mm on a birdie far away. When I turn IS on the shaking stops completely, turn it off again and vibrating shake starts again.

IMHO you should take more test photos of different objects. I'm guessing that you took these photos because you suspected that IS was degrading your photos and you found what you wanted to find.

RRS Loc: Not sure

Good Morning Gene, for BIF do you use (VR-IS) and do you hold BB down as you follow your subject or only to acquire focus prior to actually shooting .

As to this test I would think that the camera should be mounted on a tripod just to eliminate the possibility of movement on part of the shooter.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Correct, so the "halo" will occur across the entire sensor. To get a better handle on this, I would suggest you start with a flat subject, like a distant sign. The contrast between the letters and the background will give you a good indication if you have a focus issue, a movement issue or both.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

It's a pain, but I try to use panning-type stabilization, and my shutter speeds are around 1/500 to 1/1000 - so I do get some conflict between the IS trying to correct for some motion, but not as much as when I used earlier lenses with only one type of stabilization. I do hold the button down, and I do get some of the same effect that Howard is showing.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

rehess Loc: South Bend, Indiana, USA

But "electronic shutter" does cause rolling shutter issues.

Cdouthitt Loc: Traverse City, MI

of sorts...it depends on the camera.

I've found that for 95% of the things I shoot, I can get away with an electronic shutter on the EM1ii. On the previous model, it was more like 75-80%. It's only a matter of time before it's at 100%

rehess Loc: South Bend, Indiana, USA

Not supposed to use tripod and IS at the same time.

RRS Loc: Not sure

That not what Canon says and that's what I shoot.

bsprague Loc: Lacey, WA, USA

With my Panasonic GX8 and Lumix 100-400 lens, my current feeling is that IS works very well when the subject stays in one spot. It seems that if I'm trying to chase a flying bird the IS has trouble. I get slightly better results with the IS off and shutter speed in the range of 1/1300th.

One odd anomaly is that I sometimes see sharper images from 4K frame grabs. With a shutter speed higher than normal for video, the individual 8MP frames captured in Lightroom can be sharper than a 20MP RAW. I have not figured out why or if it is just an occasional accident.

For the OP, you might try using your RX10iii to shoot some 4K clips and see what you get. 8MP frames can look great on a screen and can make good prints to 13x19.

a6k Loc: Detroit & Sanibel

Yes, I do that routinely and it does produce very acceptable results. However, it does not allow the use of a small, center spot for focusing. It is a very nice way to get a good still capture with a rapidly moving subject such as a woodpecker. Notice the bug in the woodpecker's beak.

I have not experimented with IS under video. The camera allows me to turn one on and the other off which is good. It also allows the use of Shutter Priority so even though I'm only shooting 30 or 60 frames/sec, the shutter speed is still OK for fast motion subjects such as the woodpecker.

Here are two examples. An added advantage is that I can leave Clear Image Zoom on and the camera only allows it under video because I shoot either RAW or RAW+JPG.

I recommend this to anyone whose camera can do it.

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