When You Really Needed a Zoom

Fixed focal length lenses are known to be the sharpest lenses you can buy. An 85mm f/2.8, for example, is sharper than a 24-105mm lens set to 85mm. Similarly, a 500mm telephoto will be sharper than a 150-600mm or a 100-500mm lens at the same 500mm setting.

Having said that, there are important factors to think about when choosing a lens. First, the convenience of a zoom lens can’t be beat. I photographed the male lion at sunset, below, with a Canon fixed 500mm telephoto. My safari vehicle was too close to the lion to include the entire animal in the frame. I didn’t like cutting off the hind end and the tail, but there was no choice with this particular lens. I would have preferred to be shooting with a zoom, and in particular the new Canon 100-500mm lens, so I could optically pull back and include most of the tail. No doubt if my driver had repositioned the Land Rover, the lion would have moved somehow and this shot probbly would have been lost.

High quality zooms today are superb. They are very sharp. The difference in sharpness between a fixed focal length lens and a zoom with an equivalent focal length is not enough to be considered significant in my opinion. This is

particularly true when you consider the convenience of a zoom.

What happens, though, when you are too close to a subject with a fixed focal length and part of the subject is cropped out as in the lion? The only solution for this is to quickly take two pictures and then, in post-processing, combine the two shots.

With the lion, you can see on the previous page that I couldn’t move the camera to the right because I’d cut off part of his legs on the left side of the frame. Therefore, after I took this picture, I quickly swung the camera horizontally and took a second shot (shown below) that included a portion of the tail. If the cat moves between exposures, or if you change your shooting position, you may not be able to meld the two images together. That’s why you have to first identify the problem and then very quickly take the second shot.

In melding the two photographs together so the result is seemless, the first step in Photoshop is to choose the pulldown menu command, Image > canvas size. The dialog box that opens is shown above.

Adobe calls the working area of an image the ‘canvas’, and what you want to do is expand the canvas to accommodate the second image which completes the entirety of the subject. In this case, the canvas was expanded on the right side.

To do that, use the tic-tac-toe graphic in the dialog box. This represents the photograph. Click in the center left box and you’ll see arrows pointing to the right. This tells you that the expanded canvas will be on the right side of the image.

In the width field, type in a larger number than originally was shown. This is a trial and error scenario, and when I do this I prefer to expand the canvas more than I need. It can always be cropped later.

The color that fills the expanded canvas is the background color in the tools palette. It doesn’t matter what it is.

Next, using the rectangular marquee tool, make a selection in the second picture of the part of the subject that’s missing from the first shot. In this case, I selected the haunches of the lion plus the tail. I then copied this to the clipboard with Edit > copy and then pasted that (using Edit > paste) into the portion of the first picture which had been expanded. This created a layer, and the result is shown below.

At this point, move the layer in small increments to match the subject. Use the arrow keys on the keyboard (the move tool must be selected) to make these minute changes. It’s best to enlarge the photograph at least to 66% to make sure the detail in both the layer and the background match. If the background doesn’t match, and it probably won’t, don’t worry about that at this point.

Once everything matches, I flatten the layer. Then, I use the clone tool to work the background until all the colors and tones meld together correctly. In the case of the lion, I didn’t like the narrow proportion of the image which was caused by the image expansion. So, I expanded the picture again, this time by making it taller so the proportion wass more akin to the 2 x 3 ratio that comes out of our cameras. In the end, I had to use a foliage background from

another picture to fill in the image.

The above composite is the final result. As I mentioned earlier, if I had been shooting with a zoom lens, like the Canon 100-500mm, I wouldn’t have had to deal with this problem. But for those of you using fixed focal length lenses, there will be times when you will want to solve problems inherent with using a single focal length telephoto.

I had the same situation with a cheetah during a light rain, right. I was shooting with a 500mm telephoto again and didn’t want to eliminate the spray of water drops in front of the cheetah’s face by including more of the tail. The cat was too close to my vehicle to capture the entire body plus all the spray. I didn’t like the way the entire rear end was cropped out by the fixed focal length lens, so I took two shots and used this post-processing technique to solve the problem. §