Poor Man’s DSLR Focus Pulling
One of the best things about shooting video with a DSLR is the ability to use lenses with large apertures in order to have a short depth of field. This allows you to change the focal plane during the video to shift focus from one subject to another. This changing of focus can have a dramatic impact in your video but since we have to deal with manual focus (yes, there are certain exceptions) we need a way to adjust the focus on the fly without having to rely on the camera’s small LCD screen. The way filmmakers do this is with a focus puller. A focus puller is a device that allows you to control the focus of the lens by a mechanical wheel which gives you more precise control. On most focus pull wheels is an outer rim where you can use a grease pen or dry erase pen to mark different focus points so you can hit the focus right without looking at the viewfinder or LCD.
Not all of us have hundreds of dollars to spend on fancy gadgets like focus pullers but we can borrow from the concept and with a little ingenuity come up with a way to accomplish the same result.
What you will need
I hope I don’t scare you off with this extensive list of components you will need to put together.Â Ok, just kidding, odds are most of you will have the items you need lying around the house. All we are going to need are two rubber bands and a pen (I find a fine point Sharpie to work the best).
I managed to find two Sunday newspapers that I snagged the rubber bands from and stole a Sharpie off my wife’s desk.
All we need to do is to place one rubber band on the focus ring and the other rubber band on the part of the lens next to the focus ring that is not going to rotate.
To set my first focus point, I find it easier to use the photo mode’s autofocus or use Live View and zoom in close to make sure your focus is as sharp as possible. Now you make a line on both rubber bands that line up so now we have the first point. Next, we set out focus on the second focus point and mark the rubber band on the focus ring in line with the stationary band.
Now we are set to go into video mode and start shooting. When you are ready to change focus, you just rotate the focus ring to line up the second focus point line. If you are setting up multiple shots, you can use different colors of pens to correspond to different setups.
Your finished result will be entirely dependent on how well you originally set your focus points and how smoothly you can turn the focus wheel without it being jerky or moving the camera. With a bit of practice, you should be able to get pretty good results.
The video below demonstrates what you can do with this setup. The video was shot on a Canon EOS 7D with a Sigma 24-70 f/2.8 lens and is actually my very first attempts at using the setup.
As you can see, the results aren’t too bad for a first try. If you are an aspiring filmmaker on a tight budget, give this technique a try and see if you can add some nice focus pulling effects to your videos. If you have done any, please post links in the comments.