Recently we discussed a “Bokeh Technique” for a creative way of blurring the background. Today we would like to demonstrate another creative technique which is also very unique but much different in style.
Nowadays the term “zoom blur” often associates with a Photoshop filter of the same name. Like many Photoshop tools the idea for this filter came from the actual photography technique.
Zooming is a photo technique of changing a zoom setting on the lens during the exposure.
Time is a key element of photography. During the time the shutter is open there are numerous ways that the image can be altered. In our example we used a shutter speed of 6 seconds. Generally the shutter speed can be set anywhere from ½ second to 10+ seconds to achieve a desired exposure while adjusting the f-stop accordingly to get a desired look.
Note: In our example, when the Shutter Speed is set to 6 seconds the light enters the sensor for that duration of time The aperture (f-stop) needed is f-32 to compensate for the 6 second exposure. The same result could also be achieved with 3 seconds shutter speed and aperture set to f-16, but faster zooming would be necessary. (completing the zooming turn within the 3 seconds)
Using separate light sources is the key to maintaining the subject in focus while other elements and edges of the subject become blurry and zoomy.
Light # 1 was used as a main overall light. That light provided continuous light. Continuous light is the light which is constant at the beginning of the exposure and remained constant until the end.
Light # 2 Flash! I know what your thinking, there was no actual flash. However, the second light source (while being a continuous tungsten in nature) was not used during the entire exposure and was only turned on for the first 2 seconds of the 6 second exposure, which is the same concept as flash! So the second light provided not only fill light to brighten the front and the overall exposure but also froze the edges. The first 2 seconds of the exposure were not effected by the zooming assuring sharper focus on the middle of the image.
This technique can also work when photographing people. However Light # 2 would have to be an actual flash to freeze the motion during the long exposure. While light # 1 must still be a continuous light. (available room light or set up continuous lights)
Zooming during long exposures has unlimited creative possibilities and requires some time to master. It will take some practice. Then when the right moment arrives you can always find this tool in your pocket. Give this technique a try and post your results down below in comments.