Why I don’t like IBIS
Let’s consider a hypothetical situation.
You are twenty-something, you’re female and you’re on holiday in Turkey. You have a camera with a reasonably long lens over your shoulder and this young man walks out of the water in front of you.
How many of you would nail that shot first time?
How many would look at the image on the back of their camera and think ‘oh yeah!’.
How many of you would get home after your holiday and load the photo onto your computer, only to discover the images was blurred?
The image is soft, it looks out of focus, but on closer inspection you realise that it’s suffering from camera-shake.
Explanation continues after a bit of background to the shot above.
Background to the shot
I was in Bodrum (south coast of Turkey) shooting some images for a holiday company when I took this. Tom (in the photo) was working for the hotel I was staying in, part of the team who were teaching the hotel guests how to sail.
Having spotted him come out of the water, I was instantly reminded of that iconic moment in Casino Royal, when James Bond walks out of the sea and all the ladies in the theatre drew a sharp intake of breath (never happens when I walk out of the sea!).
We had a quick chat, and Tom readily agreed to reinact the Bond moment for me on camera.
Overnight I downloaded the Bond image onto my phone and then where we met up the following morning, I simply had to direct Tom how to stand.
Shooting with long lenses…
I’ve talked before about ensuring our shutter speeds are fast enough for the lenses we use.
The longer the lens, the faster the shutter speed needs to be. It stands to reason, that if long lenses magnify the image (like a telescope does), every movement is going to be magnified as well. It’s impossible to hold a lens in your hand with some movement, you just have to make sure that the shutter speed is fast enough to freeze it and prevent it ruining your photograph.
In Avoid Blurry Photos Pt.2 I referred to the simple formula to help us keep our speeds high enough to avoid camera shake.
Following that formula, for a 200mm telephoto on a full frame camera, you should be shooting at least 1/200 sec.
If you’re shooting on a crop sensor camera with a crop factor of 1.5, that speed needs to be at least 1/300* sec and if you’re using a micro four thirds system, your minimum speed should double… to 1/400**sec.
[*200mm X 1.5 = 300 **200mm X 2 = 400]
Enter Image Stabilisation (IS)
To help us get the sharp images we want, camera manufacturers have been selling us for a number of years, lenses with built-in stabilisation systems.
Inside the lens barrel there will be a floating piece of glass (suspended between electromagnets) which moves on its axis controlled by tiny gyro-sensors. These sensors detect your hand movements, compensating for them – in effect stabilising the image. The result is a sharper image, free of camera shake.
In theory, the stabilised lens will let you shoot at much lower shutter speeds than normal, sometimes as much as 3, 4 or even 5 stops slower.
Let’s say you’re still using the 200mm lens and you’ve got it mounted on a full frame camera.
From above, the minimum hand-held shooting speed = 1/200 sec
With 3 stop image stabilisation you can shoot 3 stops slower:
- 1 stop the speed drops to 1/100 sec
- 2 stops the speed drops to 1/50 sec
- 3 stops and the speed drops to 1/25 sec
Shooting on a 200mm lens, handheld at 1/25 sec…WOW!
Notice how the speed halves each time. The opportunity to shoot at these lower speeds opens up amazing possibilities, allowing you to get sharp images at speeds previously impossible.
If you haven’t come across the term yet, the acronym IBIS stands for ‘In Body Image Stabilisation’.
Mirrorless camera manufacturers like Panasonic, Olympus and Sony – and more recently Fuji (with their X-H1) have been going a different route – building IS into their camera bodies rather than the lens. In these systems, it’s the sensor that moves, rather than glass inside the lens barrel.
Choosing to put the stabilisation system in the camera has the advantage of providing stabilisation to every lens you fit… and of course, it keeps down lens production costs.
Nikon recently launched its own mirrorless cameras, the Z6 and Z7 with IBIS and interestingly, Canon have launched theirs without.
IBIS is particularly useful if you want to shoot video as it can provide a very smooth image when moving with the camera.
I am not interested in video here though as we are looking at the issue of IS from the still photographer’s point of view.
The IBIS Myth
At the moment, nearly all the camera manufacturers are jumping on the IBIS bandwagon. Whilst CANON have still to make the leap, FUJI have it in just one of their camera bodies (Fuji X-H1).
Their latest camera, the X-T3, was released without it (accompanied by much howling and gnashing of teeth from the ‘I must have IBIS on all my cameras’ brigade).
I have both the Fuji X-H1 (with IBIS) and the X-T3 (without IBIS), believe it or not, both cameras take sharp images!!
Why do we even need it?
So here’s the thing, I am at a loss to understand why there is all this ridiculous frenzy surrounding IBIS. If any manufacturer dares to release a camera without it… it’s like the end of the world.
Some of the comments I’ve come across on-line are simply hysterical.
IBIS is not the answer to life, the universe and everything. Sure, I can handhold my 200mm lens at 1/25 second and get sharp images… but what good is that is the subject is moving?
Consider a wedding
Shooting a ceremony inside a dark church with a f/1.4 50mm lens, I can gain an extra 3 stops of shutter speed, shooting at speeds as low as 1/6 second. That’s incredible.
In a wedding ceremony, virtually no one is moving. It’s a static event. Image stabilisation would be useful here.
If you then try to do that at the reception in the evening, shooting at 1/6 second during the first dance, the bride and groom will be an unrecogniseable blur.
IBIS is lulling us into a false sense of security in my opinion, making us lazy.
We are still getting blurred photos because our shutter speeds are now too slow to freeze action. Even the smallest movement of someone turning their head or moving a hand is captured as a blur.
So we’ve got rid of one type of blur (camera shake) and have replaced it with another (subject movement).
My suspicion is that manufacturers are racing ahead to put IBIS in all their cameras because of market pressure. They are afraid of being left out in the stampede.
I applaud Fuji for not putting it in all their cameras and also Canon, for not jumping onto the bandwagon.
I know from the hundreds of students I’ve taught over the years, that most of them don’t watch what shutter speeds they’re shooting at.
The majority shoot in aperture priority. The camera picks the shutter speed for you, in response to the aperture you’ve chosen. Inside the viewfinder you can see what the shutter speed is, but very, very few people take notice.
I try to train everyone who comes to me to constantly check the viewfinder readout.
The Secret Sauce to sharp images… and it’s not IBIS
If you genuinely want all your photos to be sharp, to freeze all the action in your shots, to eliminate both camera shake and subject movement shake, you’d be much better off applying a bit of self-discipline, and start taking notice of the shutter speed you’re actually shooting at.
Keep your eye on your camera readout!
This is one of those subjects where people will have their own strong views and I expect some will disagree with me.
I welcome debate and would love to hear your opinions (keep them polite or I will delete them)
If you’re looking for photography workshops, photography courses or photography lessons, check out our website at Hampshire School of Photography or call Tuesday – Friday 01252 643143