"Why would anyone ever want to try something like that?"
Apparently, lens whacking, or free lensing, allows the camera operator not only to manually manipulate the focal plane of the shot, but also allows for light to creep through the cracks between the camera body and the lens.
If you're doing it right it should look something like this:
Usually, shooting in the classic sense, (with the lens attached), is all you need. However, correct use of lens whacking can produce dreamlike, romantic-feeling sequences that are very different from any filter used in post. Usually, images produced through free lens shooting are composed of two different elements. Often, there exists one very focused element within the frame. The rest of the image tends to be sprinkled with lens flares and soft light leaks. "When you take the lens off it creates an effect, look and feeling that is totally different, you really can connect the image. Because it's real and not added in post, it's randomness gives a dreamlike quality. Its almost like how your mind remembers images and I love the feeling it gives. Its a romance, it really is." -Someone being anonymously quoted on someone else's blog
Here's a still of a shot created using the free lens technique:
"So would we just use this lens?"
- The lens should have a short focal length
- Short focal length = greater depth of field and can be set to infinity focus
- This is the main reason the lens usually needs to be of a different brand
- Small mounts allow the operator to swivel the lens without scraping or damaging the camera's body
- Lens whacking involves opening the aperture completely
- If you can't open the lens' aperture when it's not mounted on the camera, you're kind of in trouble.
"How are we supposed to control how the shot comes out?"
The main things the videographer needs to worry about when it comes to free lensing is manipulating the focus and controlling the amount/direction of the light reaching the sensor.
We'll start with the focus. There are two ways to focus when lens whacking: by tilting the lens, or by physically moving closer/farther from the subject. Although tilting the lens is by far the easiest method of adjusting the focal length, this method also allows for more light to creep into the sensor. To avoid this potential problem, the camera operator will most likely have to move forward or backward to ensure that the subject is in focus.
Now let's discuss the light. When shooting like a normal person (I.E. with the lens actually attached to the body of a camera) light can only enter the sensor from the front. Free lensing, on the other hand, allows light to hit the sensor from the sides as well. The camera operator will often manipulate the direction that the light enters by using his hand as a visor.
When light enters the sensor from the side it creates more pronounced, purposeful highlights. One can note the defined beam of light in this picture:
When light enters the sensor from the front, the picture takes on more of a uniformed wash of color/light:
I'd like to conclude this post with a segment I like to call: Erin being much too dubious about a camera technique that she's never actually tried and probably never will.
First of all, I don't believe for a second that the product created through free lensing is too random to recreate in post. In fact, creating these kinds of effects in post would give the creator more freedom to create the exact image he had in mind. Furthermore, going to out to shoot without a strong idea of what each shot should look like seems unnecessarily risky in my eyes. Despite this, I do understand why one may prefer to create this dreamlike effect on location. There's something a little bit magical about creating an effect through "natural" means rather than dropping it on a digital file later.
But then I remember how this "natural" effect is shot and I begin to worry about the camera's sensor. Most DSLR owners are known to switch between lenses with awe-inspiring speed. The main reason for this, of course, is to limit the amount of time the sensor is exposed to all of the dust and who-knows-what particles in the air. Dust on the sensor = really bad news. With this in mind, how safe could free lensing be when one has to purposefully expose the sensor to dust/debris for extended periods of time?
Hoping to be reassured, I looked to the Internet for answers regarding ways to protect both the back of the lens, and the the camera sensor while free lensing. This is what I found:
- Use an ND filter as a dust block on the sensor
- Attach some sort of optical quality polyester film like Melinex to act as a dust block
- Don't do it
For those who are successful lens whackers; I applaud you. Your skills with a camera greatly transcend mine. The shots that you can achieve on location are extraordinary and blow my mind. I'm glad you all are utilizing this game-changing technique so that I don't have to. Maybe one day I'll join the free lensing fan club. Until then, I'll thank God for After Effects.