A Quick Intro to Tilt-Shift Lenses

August 29, 2017

As Canon USA introduces three totally new tilt-shift (TS-E) lenses to the Canon EOS lens line, a quick review of what these lenses are, and their basic history, may answer some questions that new photographers might have about them.  We’ll attempt to give some general and non-technical insights into these specialized lenses in this article.  In a separate article on Canon USA’s Digital Learning Center, we’ll go into some specifics about the 50mm, 90mm and 135mm additions to Canon’s lens system.

What is a “Tilt-Shift” Lens?

This is a fair question, since the vast majority of lenses for interchangeable-lens cameras don’t tilt or shift.  Basically, tilt-shift lenses are lenses that not only allow focus, but also have a movable front section (sometimes, the middle of the lens can also move).  Moving the front section straight up or down, or alternatively to the left or right, is called “shift.”  We’re shifting a movable section of the lens, instead of leaving it in a dead-centered position.

Tilting, as the name suggests, is different.  On a lens that allows tilting, the front section of the lens can be tilted at an angle, while the rest of the lens, including the section which attaches to the camera, remains anchored in place.

There are normally knobs on the lens to perform both the tilting and shifting.  On modern tilt-shift lenses, these movements are geared, for precise control, with separate locking knobs to hold any lens movements in place, and (usually) firm click-stops at the standard, optically centered positions as well.

What Do Tilting and Shifting Do?

This is another good question, which sometimes the camera industry may not always clearly answer in a way that makes sense to new photographers.  We’ll explain both here, and try to do so in simple, basic terms.

Lens Shift
Shifting is probably the first place to wrap your mind around tilt-shift lens capabilities, partly because this was the only feature available to many photographers with these specialized lenses, back in the era of 35mm film.

Shifting is intended to correct perspective distortion.  We’ve all seen shots of a building, monument, or even a product with what we know are straight vertical lines, but in a picture, the lines appear bent inward — a bit of a pyramid effect.  Why does this happen?  It’s because we often have to aim the camera upwards to get the entire subject into the picture.

Here’s the root reason why high-end camera systems have shift lenses available.  In this image, a photographer tries to photograph an entire building.  He or she aims the camera upward a bit, to get the top half of the building in the frame.  Look closely at the result — the vertical lines, which we instinctively know are actually straight up and down in the actual building, instead appear tilted inward, toward the top of the building.  Photographers sometimes refer to this as a “pyramid effect.”

For the casual amateur photographer, this effect where the subject almost appears to be leaning backward is rarely a problem.  But for a more critical photographer, and often for a pro, it’s not enough to get the whole building in the picture — they need to accurately have the vertical lines appear straight.

Enter the shift lens.  With a shift lens on the camera, the first step is to re-aim the camera so it’s level — not aimed upward.  This alone straightens the vertical lines.  But this seems to create a problem…we can’t see the top of the building!

Then, the front section of the lens is moved upward.  As it moves, more and more of the subject (the building, in this case) becomes visible.  And, the lines stay straight, since the camera is still aimed squarely into the building, rather than angled upward.

With a shift lens, perspective distortion is corrected.  First, the camera is aimed straight into the building, instead of being angled upward.  Then, by shifting the front section of the lens, more and more of the building becomes visible, with the vertical lines of the subject staying straight.

This is a common professional technique, not only for architecture, but also for commercial shooting of products, even everyday subjects like cereal boxes for advertisements.  And as digital photography grows, more and more critical enthusiasts are beginning to see shift lenses as a way to expand their craft and the quality of work they can produce.

Lens Tilt
A totally separate type of specialized lens movement is called tilt.  As the name suggests, this means the front section of the lens is tilted or angled in such a way that it no longer is exactly perpendicular to the axis which light travels to go into the lens.

Ordinary lenses, even expensive, high-performance ones, keep the front section of the lens perfectly parallel with the image sensor (or film plane) of the camera.  When they focus, near or far, what appears sharpest is a straight, flat plane in the picture.  It’s almost as if you could imagine a large sheet of glass placed in the scene, absolutely squared-off relative to the camera.  A lens normally places its sharpest imaging on a single plane, like that hypothetical piece of glass.

That means, however, if we want sharpness to appear deep into a picture, we normally have to use a small lens aperture (high f-number, like f/16, f/22, etc.) and extended depth-of-field to get the entire scene sharp.  And sometimes, even that’s insufficient.

Lens tilt is designed to cope with this.  By tilting the front of the lens, we can change the plane of what’s sharp in the picture.  By tilting the lens so that it’s closer to being parallel to the distant part of a scene or subject, we can make more of it appear sharp.  Look at these two pictures of a long picket fence:

Two pictures of the same scene.  In the first image, taken with a 90mm tilt-shift lens but with all lens movements centered (no tilt applied), if we focus upon the nearest part of the fence, it drifts out of focus as we look toward the distance.  We MIGHT be able to get most of it sharp by using a very small lens aperture, like f/22.  But tilting offers another way to change what’s in focus.

A Quick History of Shifting and Tilt-Shift Lenses

Canon’s latest tilt-shift, or TS-E, lenses are not the first Canon lenses to offer this capability.  In fact, specialized lenses with this capability have existed for decades, dating well back to the 35mm film era.

And of course, large-format “view cameras,” popular since the dawn of photography in the 1860s, have had moveable front and (often) rear sections as well, allowing photographers very extensive perspective and focus control, when they had the time to work carefully.  So in a way, Canon’s latest TS-E lenses are a tip of the hat to camera makers from more than 100 years ago, who paved the way with lens movements in these early film glass plate and later sheet film cameras.

As 35mm film SLR cameras began to become popular in the 1960s, a few specialized shift lenses were introduced by competitive camera makers. These offered the same lens shift corrections for perspective distortion that we spoke of earlier in this article — think about the shots of the white building.

Canon’s first interchangeable lens with shifting, while not the first in the industry, was remarkable — it not only had shifting capability, but tilting too!  It was one of the first lenses for interchangeable lens SLRs with both capabilities.  This was the TS 35mm f/2.8 SSC lens, introduced in 1973.  This manual focus lens, for Canon 35mm film SLRs, offered these shift and tilt movements we discussed above, in a moderate wide-angle lens.

This is Canon’s first tilt-shift lens, the TS 35mm f/2.8 SSC lens, which was launched in 1973 — three years before the advent of the famous Canon AE-1 camera. It used Canon’s older-style, mechanical breech-lock lens mount, and was intended for manual-focus cameras of the day, such as the Canon F-1, Canon FTb, and so on.  This was one of the first lenses in the industry to have both shifting and tilting capabilities.

This lens remained in the Canon lens line through the advent of the EOS autofocus system, which was introduced in 1987.  Canon ultimately introduced a totally new series of tilt-shift lenses for EOS cameras, with the TS-E lens series in 1991.  Three lenses were launched, a 24mm, 45mm, and 90mm, each with tilting and shifting capabilities.  (A quick note — for technical reasons, all Canon TS-E lenses to date are manual focus only, even though they are designed to mount onto EOS SLRs, which of course are normally autofocus cameras.)

The TS-E series, for EOS cameras, has been part of Canon’s messaging to advanced photographers since that introduction date.  The concept has been expanded, first with an updated TS-E 24mm f/3.5L II lens and a completely new, radically wide-angle TS-E 17mm f/4L (both launched in 2009).  And in 2017, the standard and telephoto options in the Canon tilt-shift lens system are brought completely up-to-date, with the following entirely new lenses:

  • TS-E 50mm f/2.8L Macro (replaces the previous 45mm f/2.8 version)
  • TS-E 90mm f/2.8L Macro (replaces the previous 90mm f/2.8, non-L version)
  • TS-E 135mm f/4L Macro (entirely new lens, with longest focal length ever in a Canon tilt-sift lens)

Summary

The tilt-shift concept, as a professional problem-solver, remains as valid today as it was decades ago, when camera makers realized the challenges faced by working pro shooters and devised tools to help solve them.  With this latest series of TS-E lenses, Canon continues to show a commitment to our demanding users, now in a broader range of lens focal lengths than ever before in the Canon EOS series.

In our next article, we’ll examine the variety of TS-E lens focal lengths, how to consider the different choices available, and potential applications for them.

The CDLC contributors are compensated spokespersons and actual users of the Canon products that they promote.

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