Using a Tilt & Shift Lens for Distortion Correction

Tilt & Shift LensIn a post last year I discussed using Tom Neimann’s PTLens program to correct for barrel, pincushion and perspective distortions in your architectural images. Tom’s program and Photoshop plug-in filter are nothing lens than amazing at correcting distortions that are easy to overlook with the naked eye. For most of us, using PTLens is definitely the way to go.

There is another way to correct for perspective distortions however, using a “Tilt & Shift” lens such as Canon’s brand new TS-E 24mm f/3.5L II. Since I’m a newbie at using a Tilt & Shift lens I’ll leave the complete explanation and demonstration of this unique lens’ features to Bryan Carnathan at The-Digital-Picture.com. Bryan does a much better job of explaining the technical aspects of this unique lens than I ever could.

Goliad CourthouseI was fortunate enough to be able to try out this lens last year during a shoot in Goliad, Texas. I started by setting up my tripod and taking a few quick shots of Goliad’s historic courthouse using my EF 24-105mm zoom at 28mm.

As you can see in this image, the top of the courthouse seems to lean away from you and the vertical lines tend to converge. This is typical perspective distortion caused by the wide-angle lens being tilted up to capture the entire building in the frame.

Correcting this using a Tilt & Shift lens is very simple. You first level your camera on the tripod (which cuts off the top of the building in the frame) and then simply turn the shift knob until the building “shifts” down and into the frame as shown in the final image below. I finished this image very simply using Nik Software’s Silver Efex Pro plug-in filter. I find that most architectural images look best in black & white.

Goliad Courthouse

Historic Courthouse in Goliad, Texas
Copyright © 2009 Jeff Lynch Photography
Shot taken with a Canon EOS 5D Mark II set on aperture priority (Av) using an TS-E 24mm f/3.5L II lens tripod-mounted. The exposure was taken at 24mm, f/16 for 1/20th of a second at ISO 100 on Lexar Professional digital film. Post capture processing was done in Lightroom 2 and Photoshop CS4 using Nik Software’s Silver Efex Pro filter. Click on the image above for a larger version.

Using Canon’s Tilt & Shift Lenses for Distortion Correction

Lens Shifted for Perspective Correction

In a post last week I discussed using Tom Neimann’s PTLens program to correct for barrel, pincushion and perspective distortions in your architectural images. Tom’s program and Photoshop plug-in filter are nothing lens than amazing at correcting distortions that are easy to overlook with the naked eye. For most of us, using PTLens is definitely the way to go.

There is another way to correct for perspective distortions however, using a “Tilt & Shift” lens such as Canon’s brand new TS-E 24mm f/3.5L II. Since I’m a newbie at using a Tilt & Shift lens I’ll leave the complete explanation and demonstration of this unique lens’ features to Bryan Carnathan at The-Digital-Picture.com. Bryan does a much better job of explaining the technical aspects of this unique lens than I ever could.

Goliad CourthouseI was fortunate enough to be able to try out this lens last Saturday during a shoot in Goliad, Texas. I started by setting up my tripod and taking a few quick shots of Goliad’s historic courthouse using my EF 24-105mm zoom at 28mm.

As you can see in this image, the top of the courthouse seems to lean away from you and the vertical lines tend to converge. This is typical perspective distortion caused by the wide-angle lens being tilted up to capture the entire building in the frame.

Correcting this using a Tilt & Shift lens is very simple. You first level your camera on the tripod (which cuts off the top of the building in the frame) and then simply turn the shift knob until the building “shifts” down and into the frame as shown in the final image below. I finished this image very simply using Nik Software’s Silver Efex Pro plug-in filter. I find that most architectural images look best in black & white.

Goliad Courthouse

Historic Courthouse in Goliad, Texas
Copyright © 2009 Jeff Lynch Photography
Shot taken with a Canon EOS 5D Mark II set on aperture priority (Av) using an TS-E 24mm f/3.5L II lens tripod-mounted. The exposure was taken at 24mm, f/16 for 1/20th of a second at ISO 100 on Lexar Professional digital film. Post capture processing was done in Lightroom 2 and Photoshop CS4 using Nik Software’s Silver Efex Pro filter. Click on the image above for a larger version.

Using PTLens for Distortion Corrections

Columbus Texas

Columbus, Texas
Copyright © 2009 Jeff Lynch Photography
Shot taken with a Canon EOS 40D set on aperture priority (Av) using an EF-S 10-22mm f/3.5-4.5 USM tripod-mounted. The exposure was taken at 18mm, f/13 for 1/40th of a second at ISO 100 on Sandisk digital film. Post capture processing was done in Lightroom 2 and Photoshop CS4 using ePaperPress’ PTLens and Nik Software’s Silver Efex Pro plug-in filters. Click on the image above for a larger version.

If you enjoy travel, architecture or even urban photography, sooner or later you’ll run across a situation where you take a shot of a beautiful tall building but end up with an image you don’t like due to the complex distortions created by your very expensive wide-angle lens. You could use a very expensive tilt & shift lens like Canon’s new TS-E 24mm f/3.5 L II to correct the perspective distortion but what about the barrel or pincushion distortion? Luckily there is a great little tool called PTLens that can handle almost every type of complex distortion correction you’ll ever run into.

Columbus Texas Raw

Raw Image from Camera

Let’s take this image for example. I took this shot of a turn of the century bank building in Columbus, Texas using my EOS 40D and ultra-wide angle 10-22mm lens. This lens is very sharp and provides excellent contrast for most shots, but it does exhibit some pincushion distortion at the far end and like most wide angle lenses, it tends to distort the perspective when tilted up at a subject like this bank building. Correcting the perspective and pincushion distortion exhibited by this image is actually fairly simple using the process outlined below.

My first step is to develop the entire image in Lightroom 2 BEFORE CROPPING. Although this goes against my normal workflow, it’s very important not to crop the image at this point in time.

Basic Develop Settings

Basic Develop Settings

I generally work on the other Basic settings like Exposure, Recovery (very important), Blacks (also very important), Brightness and overall Contrast. I almost always crank up the Clarity (adding mid-tone contrast) and Vibrance (adding mid-tone saturation) and may play with these two settings for 20 or 30 minutes until I find a combination I like.

columbus04

Tone Curve Adjustments

Next I begin tweaking the Tone Curve controls until I obtain the contrast desired in the image. A good rule of thumb I always try to follow is to make sure you have some deep black areas and pure white areas when you’re done adjusting the Tone Curve.

Here’s a quick trick to add some contrast to your sky. Just lower the luminance of the color blue slightly to create a much more dramatic sky without it looking fake.

columbus05

Luminance Adjustments

To enhance the colors and really set the “mood” of the image I’ll generally spend quite some time playing around with the Hue, Saturation and Luminance settings. This is where you let your creative side go wild trying different combinations for each color until you obtain just the right look and feel.

Saturation Adjustments

Saturation Adjustments

The next step is to add Sharpening and depending upon your image, the tools built into Lightroom may or may not be up to the job. In this case, the mid-tone contrast of the bricks in this image is sharp enough that I can use Lightroom to add just a bit more sharpness before exporting the image.

Sharpness Adjustments

Sharpness Adjustments

At this point, my work in Lightroom is complete and my next step is to export the image in Photoshop CS4 and then run the PTLens plug-in filter. Click on the image below to see a larger version.

PTLens in Photoshop CS4

PTLens in Photoshop CS4

The PTLens plug-in reads the EXIF data from the image and automatically corrects the barrel and pincushion distortion caused by my specific lens. To see the effect of this, you can uncheck and recheck the Preview checkbox. To correct Perspective distortion you’ll need to show the Grid and then adjust the Vertical and Horizontal controls until the vertical lines in the image are truly vertical. You’ll need to play around with this for a while until you achieve the desired results.

The next step is to crop the image to remove the black areas cause by the perspective correction as shown here.  As I said earlier in this post, it’s very important to crop your image AFTER using PTLens to correct the distortion.

Cropping in Lightroom

Cropping in Lightroom

My next step is to add some darkening around the edges to highlight the center of the image. Lightroom’s Lens Correction and Post-Crop settings do a very good job of this without adding significant noise to the image. I really like how the Feather and Roundness controls allow very detailed control of the vignetting desired.

Post-Crop Adjustments

Post-Crop Adjustments

Finally a quick trip to Nik Software’s Silver Efex Pro to convert the image to black & white and we’re done.