Most filmmakers are familiar with basic lens specifications: focal length, aperture, zoom/prime… On the other hand, when we talk about coatings, types of glass, diffraction, breathing, and other advanced terms, even experienced cinematographers may become confused. Lens manufacturers make it easy for us to use their tools without much theory required. But the more we learn, the deeper our understanding of optical phenomena is, and the wider our storytelling kit becomes. Ultimately, we can communicate our creative choices much more easily. That’s what Tal Lazar’s new course, “The Art & Science of Lenses” on MZed.com is all about. In this article, we offer you a sneak peek into the first module, which helps to understand light, how it behaves, and why it is an important foundation for using lenses to their full potential.
Tal Lazar is a seasoned cinematographer and educator, who combines practical knowledge with his teaching experience at leading film schools (Columbia University, Sundance Institute, and the American Film Institute, to name a few). His new course on MZed.com is a very technical one, yet Tal finds ways to make it entertaining and easy to understand. So, don’t worry if you skipped physics class in high school. You will gain foundational knowledge in this course in no time and will then be able to apply it to lenses.
Click here to watch “The Art & Science of Lenses” on MZed.
The Art & Science of Lenses – starts with light
Lenses are tools that manipulate light. That’s why Tal Lazar begins his course with a question: “What is light?” If we can understand how it behaves, we’ll be able to explain the different optical effects that lenses sometimes have and why manufacturers make certain decisions. Put very simply:
Light is a form of energy that is emitted by a source, like the sun, and received by our eyes.
Tal Lazar
So, light travels through space. The problem is – we can’t properly see this process. That’s why over the ages, there have been a bunch of contradictory theories (including wild ones, such as the idea that our eyes emit rays of light and that’s how we can see things. Spoiler alert: no, they don’t). We’ll skip the history recap here and narrow it down to two major ways of understanding light’s essence.
Light is made out of particles
Yes, the first basic theory originally belonged to Isaac Newton. He suggested that light was a stream of particles emanating from a light source and moving in straight lines through space. This is actually easy to demonstrate. Just take a lamp and a mirror, or go to a wall and cast a shadow onto it.
See? We can easily predict how light will be reflected (and if you’ve ever played pool, you have already used the same calculations). It is also possible to connect shadow to a light source in a straight line. As Tal Lazar explains, scientists (and technicians) call this phenomenon of light traveling – rectilinear propagation.
“But the light is waves!”
– you may argue and would be correct. The second major theory states that light behaves similarly to waves. Several scientists contributed to this way of thinking, but it was Thomas Young who put a big fat point to the argument with his double-slit experiment in 1801. He set up two screens: one behind the other. The first screen had two tiny holes. The scientist cast light through them and got this result:
Instead of getting two blurry light spots, as expected, the second screen showed lines with different intensities. The particle theory suddenly didn’t make sense anymore. This behavior resembled waves. When two waves meet, a new, bigger wave is created. Where a peak and a dip meet – they cancel each other out. It is called interference. What happened in the experiment with light got the name “diffraction”.
The wave-particle duality of light
Yet, even that wasn’t the end of light exploration. Years later, Albert Einstein discovered that sometimes light could move electrons, just like electricity. (This so-called photoelectric effect won him a Nobel prize). The only possibility to explain it was that light traveled in particles, not waves. Wait, what?
That’s how a new concept was born, namely – the wave-particle duality of light. Sometimes light behaves like a stream of particles (for example, in reflection, which we discussed above), whereas other behaviors of light can only be explained as the one of waves (diffraction phenomenon, for instance).
The visible spectrum
So, when we speak of light, we have different characteristics to discuss. First, light particles are called photons, and we know that unlike traditional waves, they can travel everywhere, even in a vacuum.
At the same time, there are different light wavelengths that are measured from one peak to another in nanometers (an extremely small unit):
Tal Lazar explains that anything below 400 or above 700 nanometers is not visible to our eye. The range in between is what we perceive as different colors, depending on a particular wavelength. The famous children’s question, “Why is the grass green?” can be answered: “Because it reflects the wavelength that makes the color green and absorbs the rest of them.”
Apart from that, light travels at a particular speed (which changes, for example, when light is bent by lenses), and it has a frequency (the amount of waves passing a point in space per second measured in hertz).
Other modules of the Art & Science of Lenses
Now, we can’t see all these tiny waves or photons. However, by understanding how light works, it’s easier to predict how it will interact with matter (absorbed, reflected, transmitted, scattered, or refracted?) And then – how lenses operate and why they, for instance, create virtual images. But that’s another topic. In nearly 6 hours of “The Art & Science of Lenses” you will also:
- Learn all about basic optical devices and how they are designed and work: from internal reflection to the types of glass used to make lenses;
- Explore lens flaws that express its personality: spherical aberration, astigmatism, coma, field, curvature, and so on;
- Gain in-depth knowledge about advanced lens systems (telephoto, retro focus, macro) and special optical tools (converters, extenders, speed boosters, tilt & shift lenses);
- Dive deep into lens characteristics (aperture, depth-of-field, circle of confusion, flares, ghosting, coatings), as well as understand what changes when you use a lens on a specific camera;
- Learn how to design a lens test and make an informed decision,
…and much more. Read the description of all workshop modules here.
The Art & Science of Lenses – pricing
You can buy Tal Lazar’s “The Art & Science of Lenses” for $49.99 and own it forever. Or you can subscribe to MZed Pro and watch this course, along with over 55 other courses, for only $349 for the first year and $199 for every year after that.
As an MZed Pro member, you have access to over 500 hours of filmmaking education. Plus, we’re constantly adding more courses (several are in production right now).
For just $30/month (billed annually at $349), here’s what you’ll get:
- 55+ courses, over 850+ high-quality lessons, spanning over 500 hours of learning.
- Highly produced courses from educators who have decades of experience and awards, including a Pulitzer Prize and an Academy Award.
- Unlimited access to stream all content during the 12 months.
- Offline download and viewing with the MZed iOS app.
- Discounts to ARRI Academy online courses, exclusively on MZed.
- Most of our courses provide an industry-recognized certificate upon completion.
- Purchasing the courses outright would cost over $9,500.
- Course topics include cinematography, directing, lighting, cameras and lenses, producing, indie filmmaking, writing, editing, color grading, audio, time-lapse, pitch decks, and more.
- 7-day money-back guarantee if you decide it’s not for you.
Full disclosure: MZed is owned by CineD.
Join MZed Pro now and start watching today!
What about you? Are you interested in understanding lenses? Or do you usually skip the technical specifications? How do you make a choice when buying a new lens? Share your experience with us in the comments below!
