Heather Strong
15-463 Fall 2008
Project 0: The Vertigo Shot

In order to complete this project I used a Canon PowerShot A560. Since this camera does not have image stabilization, the biggest difficulty in this project was taking sharp photos at a large zoom. When I was in an area well-lit enough that the shutter speed was fast even with the zoom, it became difficult to see the image on the camera’s preview window. The camera has the functionality to display gridlines on the image preview window, which I found extremely helpful for lining up a series of pictures reasonably well. On the other hand, the gridlines also made me realize just how much my hands move when I’m trying to take a photo. So although I was able to see approximately how I should line up the scene, holding it in that position long enough to press the shutter button proved surprisingly difficult.

Dolly Zoom 1

My first idea for a location to photograph was Hammerschlag Hall, since this building is one of CMU’s defining images. When I went out to take test photos to see if the scene would work well, I was pleasantly surprised how sharp the pictures were. I realized that it was the brightness of the scene that was allowing my shutter speed to get just fast enough that the pictures could come out nice and crisp. I took pictures from as far back as the CFA lawn all the way up to the last of the hills sloping down towards the building. It was this large span that created the effect of the Tower of Learning shrinking away dramatically.

Dolly Zoom 2

It took me a while to come up with a second scene to photograph, since I didn’t want to just pick another building as a subject. There are several areas on campus where we have lines of columns or trees that I thought would come out well, but I couldn’t use any of those because the shade in these areas slowed down my shutter speed too much. I finally settled on photographing the vase in my kitchen, because although this area was again somewhat dim, I was able to stabilize my camera on a kitchen chair enough to prevent blurriness. The vertigo effect in this series isn’t as strong as I’d like it to be, but this was the result of having too little space to move around in.

Bells and Whistles

Moving the Subject

I had a lot of fun with this last Dolly Zoom. Between each picture, I would zoom in, move backwards, and move the dog towards me. In order to make the effect of the dog running up more dramatic, I made his head get a little bit bigger in every shot. This Dolly Zoom was easier to make than the others because I didn’t have to worry about getting the subject lined up as well in each shot because the dog had to look like he was running, not gliding. However, I again had the problem of my camera getting blurry when zooming. I turned on my desk lamp and brought over another lamp in order to get more light, and this worked fairly well. But no matter what I tried, I couldn’t get the last shot in the series to come out very clear.

Field of View Calculation

Width of Cabinet: 24 in
Distance from Camera: 200 in

Minimum Zoom:
The cabinet is 80px wide and the picture 640px wide, so the picture spans (640 px / 80 px) * 24 in = 192 in
FOV = tan-1(d / (2f)) = tan-1(192 / (2 * 200)) = 25.6°

Maximum Zoom:
The cabinet is 295px wide and the picture 640px wide, so the picture spans (640 px / 80 px) * 24 in = 52 in
FOV = tan-1(d / (2f)) = tan-1(52 / (2 * 200)) = 7.4°