The primary reason for using cinema lenses is for pulling focus. Focus pulls have become a hallmark of the cinematic look. However, cinema lenses can run anywhere from around $1,000 to over $30,000 apiece. And that doesn’t include extra expenditures like rails, matte box, follow focus, a heavy duty tripod, an external monitor, batteries, cables and more. Not only are cinema lenses expensive, but you’ll probably need an assistant or two just to get your gear to the location. In addition, it takes quite a bit of time and experience to learn to pull focus properly. This afternoon, I had a chance to play around with Panasonic’s brilliant focus transition feature along with Olympus’ sensational 45mm f/1.2 PRO lens and was fairly blown away by the results. For those not familiar with the feature, it involves setting as many as three focus points and choosing from among several transition speeds. On the slowest setting, you could probably go to Starbucks, finish a coffee and return to the set and the camera will have just finished pulling focus. It is possible to set the camera on auto and execute the focus pull without any human intervention; alternatively, you can tap on the screen to control the timing between transitions manually. Setting up the shot takes just seconds and is repeatable. And because you aren’t touching the lens while recording, there is less chance of camera shake ruining the image.
When using the feature, there is absolutely no pulsing of focus – once the camera has landed on the focus point, it remains locked there. Of course, cinema lenses have advantages other than just having gears – they are designed to have little breathing, and should have fairly consistent color across a set. They also have T stops rather than f stops for consistent exposure and always have declicked aperture rings. So those are things for a budget filmmaker to consider. But I would think that for narrative or product photography, and in other situations where the filmmaker has absolute control over conditions, Panasonic’s focus transition feature would be a welcome timesaver. Had I tried out the transition feature sooner, I might very well have never invested in cinema lenses. Couple the feature with extra teleconverter mode on the GH5 and you’re potentially saving thousands of dollars on lenses. Many filmmakers are already realizing the benefits of motorized sliders, and I believe that for many applications, the focus transition feature could be just as revolutionary.