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| Cumbres and Toltec Narrow Gauge Railway, Chama, New Mexico. Double-Headed Steam (click to enlarge) Fujifilm X-T2; 16-55mm f/2.8 lens @ 20mm; 1/500th sec. @ f/8; ISO 320 |
Some photographers welcome IS and others say it is not needed for still photography. Personally, I welcome it under many circumstances. I believe it can be beneficial and help produce a higher percentage of better images, at least for the type of work I do.
There are two types of IS. IBIS is built into the camera body and IS or OIS or Mega OIS or VR, or whatever a specific camera company may call their version, is built into a lens.
Which is better, in-body-image-stabilization or in-lens image stabilization?
The consensus seems to be that both have their positive and negative aspects. For telephoto lenses, in-lens image stabilization should work better as 1) the stabilization is designed strictly for that lens (or those focal lengths in the case of a zoom lens) and, 2) the stabilization is specifically optimized for greater hand/lens/camera movement due to the magnification of the image. In other words, a telephoto lens will magnify the image and that magnification increases the amount of stabilzation needed to produce a sharp image. The IS mechanism built specifically into a lens can handle that greater movement better than IS that moves a camera sensor a tiny amount.
On the other hand, IBIS seems to be just as good if not better for normal and wide angle lenses. The movement created by your hand is not as magnified and the manufacturers have been able to produce IBIS systems that can adequately compensate for that lesser optical movement.
Stabilized lenses necessarily cost more due to the extra research and development and costs involved with building is into the lens mechanism, which usually consists of electro magnets and at least one movable lens element.. Cameras with IBIS will cost a bit more and sometimes be a little larger than camera bodies that don't have that feature. But that trend is going away with the new generations of IBIS. I think IBIS is to the point where it is an expected feature in most new camera bodies.
From what I read, IBIS is very good, more versatile and has the advantage of either providing stabilization for lenses that don't have it and, in some cases, providing even greater effective stabilization with cameras which work in conjunction with a stabilized lens to give even a greater degree of stabilization. For example, the new Olympus E-M1X has an IBIS system that provides 7 stops of image stabilization but when paired with the Olympus 12-100mm f/4 PRO or the 300mm f/4 PRO lenses, that increases to 7.5 stops. In either case that amount of stabilization for the latest generation of IBIS is astounding.
Should image stabilization be turned off when the camera is on a tripod or when using a very high shutter speed?
There are mixed answers to this question. In the past the advice was to always turn off IS when a camera is mounted on a tripod. Also, with shutter speeds above 1/500th of a second, IS should be turned off as well.
We are now into more sophisticated stabilization systems. Some manufacturers still recommend turning off IS when your camera and lens are mounted on a tripod, others say you no longer have to and still others don't say one way or the other. Check with the manufacturer of your camera to find the definitive answer for your gear.
Also, some stabilization systems are now specifically designed to be used on a tripod and the IS switch on the lens will have a position for a tripod mounted camera. Again, check with your gear's manufacturer for specific advice.
My personal experience has been that I have found camera movement with both my Olympus and Fujifilm systems with stabilization left on with the camera on a tripod. In one test, I had my E-M1.2, using the Olympus 40-150mm f/2.8 lens mounted on a heavy, secure tripod. With IBIS on I made a number of identical exposures of a brick wall. Later, when rapidly looking through the images in Lightroom (like a slow motion movie), I saw there was differences between each image. In other words, the images were not identical as you would expect, the framing changed slightly telling me that stabilization was looking for movement and moving the IBIS system. When mounted on a tripod, you don't need your IS system looking for movement and if you press the shutter just as the system is moving, that will result in image blur.
I can say the same about my Fujifilm system. I have had my Fujifilm 100-400mm f.4.5-5.6 lens mounted on a very large, heavy, sturdy tripod and when looking through the viewfinder, I have seen the movement as I'm trying to compose. That movement was my reminder to turn off the IS in the lens otherwise I risk unsharp images.
Here is as response to a question in an article written by Shawn Steiner of B and H Photo. The article is entitled, "Image Stabilization: When To Use It And When To Turn It Off."
...it is well worth mentioning that, for the sharpest results when photographing still subjects, nothing beats a camera mounted on a sturdy tripod with the image stabilization turned off. This is because image stabilization, by its very nature, using motion along one axis to counter motion in the opposite axis, often creates varying degrees of image degradation of its own, whereas a camera firmly coupled to a stable tripod and tripped with a cable or remote release with the mirror locked in the up position will, in almost every instance, take a sharper picture.
As far as turning off IS when using shutter speeds? That, too seems to be a mixed bag. I've seen answers both ways. I don't know if it makes a difference. I normally leave mine on. If I properly conducts some tests, I may find out I need to turn it off. I just don't have a good answer to this question. You may have to conduct your own tests on your own gear to find out for yourself.
Before detaching a lens which has image stabilization, should it first be turned off?
This is an interesting topic that seldom arises. This is something I never remember to do but I will try to remember in the future. In any case, I'll defer to LensRentals.com, which I have found to be a plethora of excellent information over the years. The information below was written in one of the recent articles on their website authored by Zach Sutton entitled, "How Image Stabilization Works In-Camera And In-Lens."
Should I turn off IS before demounting a lens?
As a general practice, yes. If you have Image Stabilization activated on a lens, you’ll want to turn it off, wait three seconds, and then unmount the lens. Not doing this can potentially put the IS system in what we call an ‘unparked’ position, which means the optics are still floating, which could cause damage if shaken and jarred.Later in the comments section of the lensrentals blog entry Roger Cicala responds to a question from a reader and says:
The proper thing to do is 1) Turn IS off at the lens while the lens is still mounted to a camera. This 'locks' the IS unit in place. If you have IS on and just remove the lens from the camera, then it does not lock and off the camera flipping the switch does no good.I didn't see any information regarding turning off IBIS as opposed to turning off lens IS. I would suspect (but I'm not certain) that if IBIS is left on, damage can occur when transporting a camera. I would think you would want the IBIS system "parked" and immobile when a camera is being transported. But, as I said, I don't know for sure.
You can confirm by gently shaking the lens; there's very little noise if the IS is locked.
The locked position is safer for transporting the lens. If it's not locked the IS unit can bounce around and cause damage. How big a deal is it? I can't say for sure, but maybe 1 in 1,000 shipments that come back with IS not locked are damaged. But the incidence is 0 in 1,000; or very close to that, with IS locked.
In a DPReview forum discussing Roger's Blog entry, Roger answered the question, "Roger - would that be the best practice for ANY Canon lens with IS? Turn off IS, then remove from camera?"
Yes. We do it with every one. The most obvious 'rattlers' are the 70-200 f/2.8 and 100mm f/2.8 IS, but it's good practice. We think it's so important that it's checked twice: once when it returns from rental, and as the last check again before it's packed for it's next shipping.
That being said, damage to the IS isn't frequent even if it's left off (for example, most customers ship them back unlocked), perhaps 1 in 1,000 shipments, maybe less. But for us that can mean several broken IS units a month.
Based upon the above information, which others say is not necessary (I'll take Roger's word for it since they rent thousands of lenses every month and see this sort of thing), I will try to remember to turn off my IBIS and IS before dismounting my lenses just to be on the safe side.
I hope this post provided you with some helpful information. As I said, I'm not an expert and I would recommend you do your own research on your gear. The answers are not universal and how image stabilization works or doesn't work with your gear may be specific to your brand and not apply to others.
Thanks for looking. Enjoy!
Dennis A. Mook
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