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Tilt and shift + EOS Magazine
The shift lens isn’t always at the top of people’s priority list when purchasing a set of lenses for their camera. Once you have bought your standard and telephoto zooms, then something more wide angle and perhaps a macro for close ups, the shift comes into the category of unusual optics, along with fast, long telephoto’s and ultra-wide angles.
For taking shots of buildings however, they are invaluable. I have always had a shift lens of one type or another in my arsenal and find it an essential lens, rather than a luxury. I recently came back to Canon digital from using medium format and had for a long time been using a shift lens with a focal length of around 37mm in 35mm terms. This suited me for the majority of my shots and seemed almost like the ideal length. There were of course, times when I could have done with something wider, but unfortunately there was no wider option for this kit.
Moving back to Canon then, gave me a much wider choice. There are three shift focal lengths available, the 24mm, 45mm and 90mm. Given that I was used to using a 37mm, this was slap bang in the middle of the two wider models available. As you may know, these lenses sell for around £850 each and so to avoid a great expense, I had to choose just one model for now. The 24mm would allow me to take wider shots in confined spaces that I had so far been unable to do, whilst the 45mm and especially the 90mm where a little too long, so for me it was a simple choice, so I purchased the 24mm.
My first shots with this lens were great and I was able to shoot buildings too tall for my old system and if I was too far back, I could just crop the image to give a tighter composition.
It was only after purchasing the Canon EF1.4x II extender for my 70-200mm zoom, that I discovered that a fourth lens option was available to the range of tilt and shift lenses from Canon. Although Canon doesn’t list the 24mm tilt and shift as being suitable to be coupled with an extender, it does in fact fit and works fine.
Because the shift lens uses the centre part of the lens to produce the image, the image quality doesn’t suffer so much with edge softness as other lenses do when combined with a teleconvertor, so you get the best of both worlds.
An architectural photographer will probably have all three models in his kit bag to cover every eventuality, but the two widest combinations, plus the extender would be more than suitable for most people. The 24mm is great in town centres and on really tall building or cathedrals or anywhere where the space is tight behind you and you cannot move back far enough. Combined with the 1.4x extender, gives me the best and most useful focal length, suitable for the most common situations where you can move back and have space around you. The 45mm has slightly more limited appeal. In the right situation where you can’t get close to a building, it would prove invaluable, but for most cases it proves to be a little too long and usually cuts into the sides of the building in question. Anyway a little space around the building you are photographing is no bad thing.
In practise, a camera with a tilt and shift lens should really be used with a sturdy tripod. It’s no use investing in one of these lenses, if you are going to tilt the lens up accidentally whilst trying to handhold it. A hotshoe-mounted spirit level is also an essential accessory, to make sure everything is straight and level to start with. All three Canon shift lenses are manual focus, so it back to old school methods and this too will slow you down, so don’t try to rush your shots. The Live View and grid feature on the new EOS 1D MkIII and EOS 1Ds MkIII, make composing the shot with a shift lens a lot easier too.
It really comes with practise to realise which shift lens is most suitable for your needs. By combining your choice with a teleconvertor really opens up the options available to you however. If you think that you need to go wide sometimes, but still want the longer length option, then like me the 24mm is the best choice. If the 45mm seems wide enough, then this may be the only shift lens you will ever need. You can always make it into a 90mm with a 2x teleconvertor, giving you the best of both worlds that way. If you need even more convincing that a shift lens is an essential purchase, go back and look at your old pictures and see how many of your pictures have converging verticals. Old buildings especially will benefit to keep their grand and majestic look and a shift lens is the best tool to treat these with the respect they deserve.
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How a tilt and shift lens works
If, when photographing a tall building close up, you tilt the camera up with a normal lens fitted, the building will look as if it is falling over as the sides lean inwards. This is known as converging verticals. With a shift lens you keep the back of the camera completely vertical and use the shift feature to raise the lens axis up. As you do so the top of the building will come back into the frame in the viewfinder whilst the sides of the building remain straight, as they should appear. A small knob on the side of the lens raises the lens up or down 11 degrees in either direction. An even smaller knob on the opposite side locks the lens in the set position if required. On the adjacent side to these two knobs are two further adjustment knobs. These are for the tilt feature, one for adjustment and the other to lock the position. These tilt the lens up to +/- 8 degrees relative to the sensor plane. The result is a focus plane that is not parallel to the sensor plane. A further metal plated lever allows the lens to rotate to allow these two functions to operate at 90-degree angles to their original positions, i.e. to shift up and down or shift left to right.
Six possible focal length combinations:
24mm
24mm +1.4x = 34mm
45mm
45mm + 1.4x = 63mm
90mm
90mm +1.4x = 126mm
Each model compared
24mm
Great for tight spaces and really tall buildings
A great wide angle landscape lens
Allows you to include foreground features in front of the building rather than exclude them
24mm + 1.4x
Most useful and for me the most used combination
If a building can’t be framed horizontally with this combination, it usually will when vertically orientated
The design of the shift lens means that image quality doesn't really suffer too much
24mm and 33mm shift lens for the price of one, plus the cheap teleconvertor
45mm
Useful for tight crops
The standard focal length means that there is less chance of any pincushion effect
Combine with a 2x telconvertor to get a cheaper 90mm shift option
Makes a great standard lens
90mm
The first shift lens available by canon, but also the sharpest
More limited versatility
Has nearly no light fall-off even wide open f2.8, compared with the wider models
Great, if unconventional portrait lens
Great close up or product shots lens
Advantages of shift lenses
Without shift, it works as a standard fixed focal length
It stops converging verticals which ruins the look of buildings, especially older types
They can be shifted down as well as up, if you need to make more use of foreground.
With the shift function at 90degres, it can be shifted sideways and allow you to crop out unwanted distraction on the edge of a frame, without moving your position.
The tilt function is great for increasing foreground depth of field just like on a large format camera.
Use the tilt function and a wide aperture to blur any distracting background
You can increase the converging effect that you get with a fixed lens, by shifting down and then pointing the camera up. Great for really unusual compositions.
A shift lens rotated 90 degrees makes a great lens for creating panoramics- shoot three images at each setting left shift, normal and right shift and then stitch together
Shift lenses with a crop 1.6x crop sensor
24mm becomes a 38mm as standard
45mm becomes a 72mm as standard
90mm becomes a 144mm as standard
If you are the owner of a crop sensor camera (EOS 1000D/400/40D etc), then the range of these lenses automatically becomes less. With the 24mm, your widest focal length becomes 38mm. This is the focal length I used for many years on medium format and as mentioned works for 90% of subjects. You will come across buildings that are just too tall however and you have to find an alternative viewpoint for these. If you are serious enough to be contemplating owning a shift lens, then maybe a full frame Canon EOS camera should be high on your list. Unless of course Canon decided to release a 15mm shift lens…..!
© Craig Roberts
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