A Discussion on IS

[MLCIII]

I often use the classic focal length to shutter speed technique in trying to maximize sharpness. 100mm and 1/100 sec or faster, for example. I'd like to hear some discussion on your personal experience with this technique and whether you feel Image Stabilization has really helped improve your photography.

 

[Ysarex]

Yes, IS is effective and I rely on it to give me that extra edge.

The classic 1/focal length rule for hand held photography is bogus. There are way too many other factors involved. Camera mass for example is a critical factor. I did tests for this years ago: Mass = inertia; more inertia = sharper photos at slower shutter speeds and vice versa. Are you using plastic lenses on a featherweight plastic camera? If you're taking hand-held photos and you want sharp photos get a heavier camera -- the heavier the better. Add a grip to add weight. The general move over time has been toward lighter cameras and as a result 1/focal length has become 1/focal length +1 or even +2.

There really is a differential operating with that rule. On the wide end the rule relaxes so that if you're shooting say a 20mm lens on a 35mm camera and the camera weighs a respectable 3+ pounds you may be able to pull off a 1/15th sec. hand-held shot. However on the other end if you're shooting a 200mm lens on that same camera, good luck getting a sharp photo at 1/250th sec.

Joe

 

[Dao]

IS/VR/OS/VC are one of the technology which I do not consider as a gimmick. It is a nice option to have in a situation that you need it. But it is not a must have.

 

[MLCIII]

Of course there are other factors, but I've always respected it as a guideline. I wouldn't call it bogus.
You make a good point about the weight. When I moved from my cheapo xsi to my 7D I noticed I could steady the camera much more easily. I attributed it to the larger size and better ergonomics with the grip, but the thing is also much heavier.

 

[amolitor]

Digital has also allowed the use of slower shutter speeds in the following fashion: Take as many identical shots as you can, doing your best steady-holding techniques for each one. One of those images will be the sharpest one. Use that one. You can probably get another stop this way, if you can get, say, 10 exposures off.

 

[KenC]

Yes, it's very useful. As Joe says, the difficulty is more with long lenses. Having IS allows for a sharp image at 1/focal length above 100 mm, where this otherwise would be tough, and it even gives good results slower than that. I've had pretty good luck at 1/125 or even 1/60 at 300 mm. Even with the shorter focal lengths, 1/focal length is probably not enough for close-up shots without IS.

 

[TCampbell]

My experience is that IS works more often than not... but is not foolproof. I use it, but I try to avoid relying on it. In other words if I can shoot with a fast enough shutter speed that I wouldn't need IS, then I will.

If you think about the mechanics of how IS works, it makes sense that it can only control a limited amount of movement. Elements are physically moving to compensate for your movement. At some point the elements hit the limit of travel within your lens.

I've seen some lens reviews which specifically test for IS performance... e.g. shooting at 1 stop under, 2 stops under, and so on to see how far they can push the IS system and still get acceptable images. Nearly all lenses with IS will do great at 1 stop under and usually also 2 stops under. Many lenses start to become much less reliable at 3 stops under and few lenses perform well at 4 stops under even when the IS system is rated for 4 stops (although there's often "some" improvement over no IS at all... you do still see some motion blur.)

It should be noted (because I occasionally see this mistake) that IS only helps correct for camera movement... not subject movement. I recall seeing a Canon lens brochure showing off IS where they were taking a picture of a child on a swing and showed the difference between IS and no IS. It was a HORRIBLE example (great to sell lenses though!). A child on a swing is moving forward and backward like a pendulum... that would have been a MUCH better photo to show off the difference between single focus and continuous servo focus (aka Canon "One Shot" vs. "AI Servo" or Nikon AF-S vs. AF-C). The image implied that the IS was correcting for that movement (and of course they showed a blurry "without IS" shot and a sharp "with IS" shot.) With marketing like that, it's no wonder people are confused about what it does and how it works.

If I'm really concerned about motion blur, I'll use IS, but I'll also consider how I might be able use a stable platform (tripod, monopod, resting the camera ledge, railing, lean against a pillar, etc.)

 

[Overread]

One thing that oft gets forgotten and that I think is worth mentioning is that when one uses IS you not only counter motions for the shot, but also for the viewfinder. Personally I find that, esp with a heavier lens, this makes the act of framing a shot on a long focal length at a lot easier. The image is steadier and thus its much easier to see the subject, frame the subject and keep the frame in position.

 

[TCampbell]

One thing that oft gets forgotten and that I think is worth mentioning is that when one uses IS you not only counter motions for the shot, but also for the viewfinder. Personally I find that, esp with a heavier lens, this makes the act of framing a shot on a long focal length at a lot easier. The image is steadier and thus its much easier to see the subject, frame the subject and keep the frame in position.

And... while we're at it, it does make it easier for the camera to lock focus before the shot. Canon's seminar on their auto-focus system actually recommends that action photographers leave the image stabilization mode ON even when they're shooting at extremely high shutter speeds that don't "need" the IS. It's because the IS helps the camera's AF system lock focus faster and more accurately.

 

[Gavjenks]

Maybe not in the extreme example of a child on a swing moving toward you, but in most fast-movement-of-the-subject situations, IS does indeed help.

Not because it compensates for subject movement, but because often, you will be panning your camera to match the subject, and you don't care if the background is blurred (or may often even want the background to be blurred).

You do need a lens with horizontal panning style IS as an option, though. Or it will make your panning all jerky and weird.

 

[JohnTrav]

IS has come in handy for me a bunch of times. And I also find myself in situations where I wish it were on some of my lenses. Especially my 70-200 f/2.8. I bought the non-IS to save some cash and still have the fast glass. It takes amazing pictures and the quality is great. But the weight of the lens can cause some shake and I find myself in situations with no tripod or monopod wishing I had IS on it.

When I shoot sports I never have a need for IS though. I have only shot in broad daylight though since I mainly shoot paintball and that is when it is played. I always have shutter speeds of about 1/500-1/1000. So in that case it will eliminate any camera shake pretty much. I also use a canon 70-200 f/4 model though to shoot paintball since it is lighter weight and cheaper on my wallet if it were to get shot and break.

When I have shot other events for people I do not rely on my IS that often though because I use flash. Mainly when the flash fires it will freeze the subject I took the picture of and it will come out very sharp. Only time I have had any come up unusable was user error on my part.

In conclusion. I think IS is nice to have. I don't think it's a necessity because if you don't have it there are ways to get around that and still take great shots. If budgets are good enough though I would personally always spring and get IS on the lens if it is an option. It's a great feature and really can save images in some situations.

Also some people say that a great tripod trumps IS any day

 

[grafxman]

I often use the classic focal length to shutter speed technique in trying to maximize sharpness. 100mm and 1/100 sec or faster, for example. I'd like to hear some discussion on your personal experience with this technique and whether you feel Image Stabilization has really helped improve your photography.

I haven't used the classic technique since the '60s. As for IS, much depends on how long your lens is and how much light is present. If you're shooting a short lens in bright light and using a high shutter speed the IS is likely of little if any value. On the other hand, if you're shooting a long lens on an overcast day the IS can be a photo saver. If you're shooting from a tripod then it doesn't matter because the IS is supposed to be disabled when shooting from a tripod. If you're shooting hand held photos, especially with a long lens then IS is virtually essential. I feel IS allows me to get hand held shots at 1000 mm such as these:

IMG_0590 | Flickr - Photo Sharing!

IMG_0583 | Flickr - Photo Sharing!

IMG_0587 | Flickr - Photo Sharing!

The shutter speed is pretty high but in many situations it's better to have IS than to not have it.

 

[MLCIII]

Seriously, the 60s? I think it's still a relevant technique even with the crazy ISO and noise reduction capabilities today.
Thanks for everyone's inputs, I'm glad to know it actually pays off.

 

[grafxman]

Seriously, the 60s? I think it's still a relevant technique even with the crazy ISO and noise reduction capabilities today.
Thanks for everyone's inputs, I'm glad to know it actually pays off.

I'm not saying the technique isn't valid today that's all. It may very well still be valid. BTW, I was shooting a Nikon Photomic Tn back then.