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This is a view of downtown Charlottesville Virginia on a summer day in 2011 taken from the summit of Montalto, which is adjacent to Monticello. Historic landmarks like the Rotunda at UVA are visible as well as newer landmarks like the Charlottesville Pavillion. The panorama was created by stitching together 12 overlapping images. The source images were taken with a Canon 1DsMIII and a Canon 135mm F/2.0L lens.

Extending the sky upward to alter composition.

1. The lawn hadn’t been established and was enhanced using Photoshop.
2. The black light pole on the left was cropped out of the final image.
3. Obviously it is always best to compose in the camera. But in architectural photography, it is also important to maintain a level camera to prevent distortion of lines. Because of the slope of the land, I had to place the building in the vertical center of the frame when the exposure was made. I wanted the final composition to have the building be lower in the frame, at about 1/3 from the bottom. So I extended the sky upward and cropped out some of the foreground grass to achieve the final preferred composition.
4. The pavement was darkened using a curves adjustment.
5. I “harvested” the blue Virginia State flag seen in the final image from another exposure taken moments before so that it would be flying in concert with the American flag.
6. The white plastic PVC pipes along the roadway were removed.

Simply put, dynamic range is the range of brightness values, from shadow to highlight, in a given scene. Cameras don’t have nearly the dynamic range of the human eye. When a scene is high in contrast, the camera can’t record all the disparate brightness levels. Either the shadows will be recorded as pure black or the highlights will be recorded as pure white, or both.

A solution is to take a series of bracketed exposures at different exposure values capturing the extremes of shadows and highlights.

Shown below is the set of source exposures that were combined to generate the final image shown at the start of this post.

The simplest way to combine the differently exposed frames is to stack the exposures in Photoshop and use layer masking to hide/reveal certain parts of each image. This is the manual approach.

Two automated approaches also exist. The first automated approach combines exposures to create an intermediate 32-bit HDR image which is then “tone-mapped” into a low dynamic range image. Tools such as Photomatix use this kind of HDR processing. These tools are quite popular for creating other-worldly, surrealistic images. But for commercial work, the results can be unrealistic or in some other way unacceptable.

A second automated approach is known as exposure fusion. The fusion software employs algorithms to analyze and select which pixels to use from each of the source images to create a fused result. The product I use for exposure fusion is called Enfuse.

I usually use a combination of exposure fusion with the manual approach. That is, first I’ll create a fused image from the series of differently exposed frames. Then I’ll select the most-correctly-exposed individual frame as a basis for the final image. Starting with this single exposure, I’ll then blend in (with layer masking) the fused image to reveal details in highlights and/or shadows that the single exposure lacks.

This usually involves trial and error, and patience.

There are many ways to capture the source images for stitched panoramas. These range from hand-holding to using specially calibrated panorama heads. Today, I’ll discuss an approach that uses the shift feature of Canon’s 24mm tilt shift lens to create a vertically stitched panorama.

One reason for creating a panorama is to capture an entire scene that won’t fit in a single frame.

Why not just back up farther to get the whole scene in the frame? There may be a busy road or a structure preventing you from doing so. Or objects (like a tree) may occlude the scene making it necessary for the camera to be in front of the obstruction.

Why not just rotate the lens to portrait orientation? This may cut off too much of the horizontal context of the scene.

Why not just use a wider lens? This may create unacceptable distortion. While wide-angle distortion has its place as a creative tool, controlling vertical lines is often a requirement for architectural photography.

A few words about the source images: The three source images shown above were each created by combining 5 bracketed exposures to achieve the high dynamic range shown. In this case, I used the tool known as Enfuse. The stitching was done using CS5 Merge to Panorama command. After stitching the panorama, further refinements to exposure and contrast were made in Photoshop. The final shot was also retouched to clean up the foreground.

A few words about the lens: The new Canon 24mm tilt shift lens (Canon TS-E24mm f/3.5L II) is a vast improvement over the first generation version of this lens. In particular, the near elimination of the chromatic aberration issues that plagued the first generation version and the unbelievable sharpness make this my go-to lens for architecture work. It is also much more flexible, enabling shifting horizontally or vertically. If you want to read a review about this lens you can do so here.

One tool in my arsenal is an extra tall camera stand made by Bogen Manfrotto. It measures 24′ at full extension.  In my setup, the camera is tethered and operated remotely via a laptop which is connected to the camera with powered USB extension cables.  The camera sits on a motorized pan/tilt head (really designed for video) so that I can control the angle and perspective of the shot.

The rig needs stabilization above 10 feet or so, even if there is hardly a breeze. To that end, there are guy lines that can be tied or staked into the ground. I also have lots of sandbags at the ready.

This shot was taken from the widow’s walk of a nearby building with the tripod at full extension.

When a ladder or cherry picker is too low, and manned aircraft is too high, a tethered helium balloon fills the gap in altitude from 50′ to 500′.  I use a setup from Southern Balloon Works.

The balloon is tethered with two lines. The camera is attached to the blimp and supported on a custom housing which is radio-controlled via a ground station.  The ground station includes a monitor so you can preview the image.  It also has controls for pan, tilt, zoom and shutter release.  The camera housing has a set of gears that enable zooming of the lens remotely. The housing itself allows control of pan and tilt.

Here are two photos of the same property, taken from two different altitudes, with the helium blimp.