I am a low budget photographer. Once a year, I set up a photo studio in my living room to take portraits of my family. Rather than purchase high cost studio lights for this purpose, I typically use low cost construction lights, although I recently picked up a high intensity movie light at an estate sale.

Both light sources have a color temperature of between 3200 and 3400 Kelvin. Sunlight has a color temperature of 5500 Kelvin at high noon on a sunny day. While the color temperature of the light is not an issue when I shoot using black and white film, which I have done in years past, this year, I decided to shoot using color print film.

Unfortunately, color print film is designed to record images under daylight lighting conditions. While a photo flash produces light with the same color temperature as daylight, my flash unit has died and I have not yet replaced it. And in any event, the flash is not sufficient to light my subject appropriately.

Below is a photograph of a scene shot in color using my budget lighting sources without modification. As you can see, the 3200 to 3400 Kelvin light sources leave a yellow color cast over the whole scene.

In order to rectify this situation without breaking the bank, I decided to change the color temperature of the light using reflectors. Fortunately, I had a reflecting umbrella with a blue tint to change the light temperature for the movie light, but my other reflecting umbrella had a silver surface, which did not change the color of the light. So what I did was purchase blue foil wrapping paper from the Party Store to line the inside of my second umbrella. Then, when I shine my construction lights into the umbrella, the reflected light has more blue in it thereby converting my 3200 Kelvin light to a 5500 Kelvin daylight equivalent. Below is a photo of the lighting set up.

When I shot the same scene using the blue modified light, the colors were much more natural, as shown in the photo below.

The other way to change the color temperature of the light would be to use an 80A or 80B lens filter. With the light sources I was using, an 80B would be the appropriate filter. However, doing so likely would have required a greater exposure compensation than would be required using the umbrellas. Because the blue filter reduces the amount of light that passes through the lens to the film, the shutter must remain open a longer period of time to make the photo. Below is a picture of my 80B filter.

I enjoyed my foray into the science of light and the process of light modification necessitated by my desire to shoot this year’s portraits using color film.

Light always plays a part to a greater or lesser degree in any photograph. Sometimes, as was the case the morning of June 30 when I captured the image in this post, light becomes a compositional element in the photograph.

But light can be a fickle subject. She is prone to fool your lightmeter, claiming for herself center stage, causing your camera to underexpose your main subject.

Light also can be elusive. While she is eager to show herself in all her glory, she will do so for but a moment. The photographer must act quickly to capture her on film before she slips away to hide in the full glare of the sun.

A photographer will be well served to learn the secrets of natural light.

One may surmise by looking at my Photo Gallery that I pay close attention to depth of field when taking photographs. Depth of field is the technical phenomenon that causes some parts of a photograph to be in focus and some to be out of focus. Depth of field traditionally has been caused by the relationship of the lens aperture (the size of the hole that lets light into the camera) and the size of the film. The larger the piece of film, the shorter the depth of field (meaning more of the image will be out of focus). That is why large format view cameras tend to produce images with a short depth of field at many aperture settings. As the film one uses gets smaller in size more of the image is in focus. Hence, 35mm cameras allow for a more in focus image than medium and large format cameras.

I took the photograph above, Country Store, with a 35mm film camera. I was able to set the film camera so that my subject, the woman in the back room, is in focus, and everything else in the foreground is out of focus. In my view, this short depth of field which empasizes certain elements of the image makes a much more interesting photograph than if everything was in focus. Country Store is featured in the Travel Portraits gallery at www.wmgphoto.com

To learn about the challenge of creating a short depth of field using a digital camera, click here ——>

In the Renaissance Acrobat Image shown here (which I shot at the 2007 Maryland Renaissance Festival), it appears that the depth of field created by the camera put the subject in focus and the background out of focus. Such is not the case, however. The problem is that I shot this photograph with a digital 35mm camera, and digital 35mm cameras (with only a few exceptions) have image sensors (i.e. the “film” of the digital world) that are smaller than a regular 35mm piece of film. Consequently, try as I might, I cannot set this camera to give me a short depth of field.

In this photograph straight out of the camera both the foreground and the background were in focus, and the background was so busy that it overwhelmed the subject. In that form, this was not a very interesting photograph. Fortunately, I was able to isolate the foreground and apply a photoshop filter to the background to reproduce the guassian blur that would have occured had I been able to set the camera to give me a short depth of field.

This post-production digital manipulation was a tedious process, and I much prefer to set up the camera to give me the depth of field I desire.