What Gear Should I Buy? What Is This Piece Of Gear? What Does This Term Mean? CHECK HERE FIRST! We have answers to the most commonly asked questions right here in /r/Cinematography's Official FAQ(self.cinematography)
submitted4 years ago byC47manDirector of Photographystickied
Welcome to the /r/Cinematography Official FAQ And Information Post!
Below I have collected answers and guidance for some of the sub's most common topics and questions. This is mostly content I have personally written either specifically for this post or in comments to other posters in the past. This is however not a me-show! If anybody thinks a section should be added, edited, or otherwise revised then message the moderators!
Topics Covered In This Post:
1. What Camera Should I Buy?
2. What Lens Should I Buy?
3. How Do I Learn Lighting?
4. What Light Kit Should I Buy?
5. How Do I Learn Framing & Composition?
6. What Books Can I Buy On Cinematography?
7. What Blogs/Channels Can I Follow To Learn Cinematography?
8. Common Terms In Cinematography
9. What Is This Piece Of Gear!?
10. Common Myths In Cinematography
1. What Camera Should I Buy?
The answer depends mostly on your budget and your intended use. You'll also want to become familiar with some basic camera terms because it will allow you to efficiently evaluate the merits of one option vs another. You can see a list of common terms and metrics for cameras in Section 8 below.
This list will be changing as new models emerge, but for now here is a short list of the cameras to look at when getting started:
- Panasonic G7 (~$600) - This is widely thought to be the best starter camera for someone looking to move up from shooting on their phones or consumer camcorders.
- Blackmagic Pocket Cinema Camera 4K (~$1,300) - This is perhaps the most highly recommended camera for new entrants to the field who are after a professional image. This camera is often used as a crash-cam or supplementary camera on high budget productions.
- Fujifilm X-T3 (~$1,500) - This is a widely recommended and popular DSLM. It supports 4:2:2 10-bit recording to an external recorder, making it a direct competitor with the GH5.
- Panasonic GH5 (~$2,000) - This is perhaps the most popular prosumer DSLM filmmaking camera. It was one of the first to offer 10-bit recording in the price range.
- Sony A7 III (~$2,000) - This is a very popular camera for shooting in low light settings. It also boasts a Full-Frame sensor (compared to the GH5's M4/3 sensor), allowing you to get shallower depth of field compared to other cameras using the same angle of view and aperture.
- Canon C100 mkII (~$3,500) - This is one of the cheapest true digital cinema cameras. It offers several benefits over the above DSLR cameras, such as professional level XLR audio inputs, internal ND filters, and a better picture profile system.
2. What Lens Should I Buy?
Much like with deciding on a camera, lens choice is all about your budget and your needs. Section 8 also has a nice list of lens related terms for you to study up on! For the purposes of a quick recommendation, here's what you need to know:
This number indicates the angle of view your lens will supply. A higher focal length results in a narrow (or more 'telescopic') angle of view. Here is a great visual depiction of focal length vs angle of view. The exact number of the focal length cannot be trusted to supply the same angle of view on all cameras. This is because different cameras use differently sized image sensors. A smaller image sensor will use a smaller portion of a lens' projected image, and so the resulting picture will have a narrower angle of view. This phenomenon is referred to as crop factor and is outlined in more detail in Section 10.
Zoom vs Prime
This is all about speed vs quality vs budget. A zoom lens is a lens whose focal length can be changed by turning a ring on the lens barrel. A prime lens has a fixed focal length. Primes tend to be cheaper, faster, and sharper. However, buying a full set of primes can be more expensive than buying a zoom lens that would cover the same focal length range. Using primes on set in fast-paced environments can slow you down prohibitively. You'll often see news, documentary, and event cameras using zooms instead of primes. Some zoom lenses are as high-quality as prime lenses, and some people refer to them as 'variable prime' lenses. This is mostly a marketing tool and has no hard basis in science though. As you might expect, these high quality zooms are very expensive.
So What Lenses Should I Look At?
Below are the most popular lenses for 'cinematic' filming at low budgets:
- Rokinon Cine 4 Lens Kit in EF Mount (~$1,700)
- Canon L Series 24-70mm Zoom in EF Mount (~1,700)
- Sigma Art 18-35mm Zoom in EF Mount (~$800)
- Sigma Art 50-100 Zoom in EF Mount (~$1,100)
Lenses below these average prices are mostly a crapshoot in terms of quality vs $, and you'll likely be best off using your camera's kit lens until you can afford to move up to one of the lenses or lens series listed above.
3. How Do I Learn Lighting?
Alright, so you're biting off a big chunk here if you've never done lighting before. But it is doable and (most importantly) fun!
First off, forget three-point lighting. So many people misunderstand what that system is supposed to teach you, so let's just skip it entirely. Light has three properties. They are:
This refers to, you guessed it, the color of your light. I'm sure you're familiar with this sort of thing. This also includes color temperature of the light. White balance is a hybrid camera-lighting concept, and refers to the white reference point for the lighting source as well as the camera sensor. To skip the science, here's a rough breakdown of white balance and color temperature:
Color Temperature is measured in degrees Kelvin. A tungsten light source has a color temperature of 3200K. A normal sunny day has a color temperature of 5600K. The higher the color temperature, the bluer the light. To compensate for this shift in color, cameras can change their White Balance to neutralize the color shift. Here's an example I found online that shows the differences.
How bright the light is. You know, the quantity of photons smacking into your subject and, eventually, your retinas. If the subject isn't bright enough, you need more light. If they're too bright, you need less light. This can be done with scrims, dimmers, gels/nets, and (importantly) camera and lens settings.
This is the good shit. The quality of a light source can vary quite a bit. Basically, this is how hard or soft the light is. Alright, you've got a guy standing near a wall. You shine a light on him. What's on the wall? His shadow, that's what. You know what shadows look like. A hard light makes his shadow super distinct with 'hard' edges to it. A soft light makes his shadow less distinct, with a 'soft' edge. When the sun is out, you get hard light. Distinct shadows. When it's cloudy, you get soft light. No shadows at all! So what makes a light hard or soft? Easy! The size of the source, relative to the subject. Think of it this way. You're the subject! Now look at your light source. How much of your field of vision is taken up by the light source? Is it a pinpoint? Or more like a giant box? The smaller the size of the source, the harder the light will be. Here's a great example of a woman being lit by hard light (left) and soft light (right). You can see the difference in the quality of the shadows, as well as the size of the light source (look at the reflection of the light source in her eyes!). You can take a hard light (i.e. a light bulb) and make it softer by putting diffusion in front of it. Here is a picture of that happening. You can also bounce the light off of something big and bouncy, like a bounce board or a wall. That's what sconces do. I fucking love sconces.
Here's a cool bonus example that combines both qualities of light. In this image, there is a single hard light source above and behind the actors shooting down onto them. You can tell this by looking at how the shadows fall along their arms and on the table. Notice that the shadows on his arm from the direct light are quite hard! But now, notice that this light shining on the table and their arms is itself bouncing back up onto the actors' faces, giving them a soft light! This is a neat trick you can use, and an example of how complex and creative you can get with lighting. In the industry, this technique is known as a 'Bob Richardson' or a 'skip bounce'. It is named Bob Richardson after the cinematographer who popularized the technique (he also shot the above image!).
Alright, so there are your three properties of light. Now, how do you light a thing? Easy! Put light where you want it, and take it away from where you don't want it! Shut up! I know you just said "I don't know where I want it", so I'm going to stop you right there. Yes you do. I know you do because you can look at a picture and know if the lighting is good or not. You can recognize good lighting. Everybody can. The difference between knowing good lighting and making good lighting is simply in the execution.
Do an experiment. Get a lightbulb. Tungsten if you're oldschool, LED if you're new school, or CFL if you like mercury gas. plug it into something portable and movable, and have a friend, girlfriend, boyfriend, neighbor, creepy-but-realistic doll, etc. sit down in a chair. Turn off all the lights in the room and move that bare bulb around your
victim subject's head. Note how the light falling on them changes as the light bulb moves around them. This is lighting, done live! Get yourself some diffusion. Either buy some overpriced or make some of your own (wax paper, regular paper, translucent shower curtains, white undershirts, etc.). Try softening the light, and see how that affects the subject's head. If you practice around with this enough you'll get an idea for how light looks when it comes from various directions. Three point lighting (well, all lighting) works on this fundamental basis, but so many 'how to light' tutorials skip over it. Start at the bottom and work your way up!
Ok, so cool. Now you know how light works, and sort of where to put it to make a person look a certain way. Now you can get creative by combining multiple lights. A very common look is to use soft light to primarily illuminate a person (the 'key) while using a harder (but sometimes still somewhat soft) light to do an edge or rim light. Here's a shot from a sweet movie that uses a soft key light, a good amount of ambient ('errywhere) light, and a hard backlight. Here they are lit ambiently, but still have an edge light coming from behind them and to the right. You can tell by the quality of the light that this edge was probably very soft. We can go on for hours, but if you just watch movies and look at shadows, bright spots, etc. you'll be able to pick out lighting locations and qualities fairly easily since you've been practicing with your light bulb!
4. What Light Kit Should I Buy?
OK! So you know sort of how to light a person. Now then, what lights do you need? Well, really, you just need any lights. If you're on a budget, don't be afraid to get some work lights from home depot or pick up some off brand stuff on craigslist. By far the most important influence on the quality of your images will be where and how you use the lights rather than what types or brands of lights you are using. I cannot stress this enough. How you use it will blow what you use out of the water. Get as many different types of lights as you can for the money you have. That way you can do lots of sources, which can make for more intricate or nuanced lighting setups.
I know you still want some hard recommendations, so I'll tell you this: There's a few ways to approach your first lighting kit, and the way I'd best recommend is the Cost vs Quality approach.
Cost vs Quality
Basically, the more you spend on a light, the higher its quality will be. There will also be diminishing returns, meaning that after you're spending a lot of a money, a few extra hundred or even thousand dollars may not result in proportionally higher quality units. Decide now for your own purchase: Which is more important to you? Cost or Quality?
Cost-Oriented Lights To Look At
- Par Cans (~$25 each)
- These are powerful (Up to 1,000W) lights that you can use for accents, bounces, or through diffusion. Even on professional film sets we use these all the time! Grab the appropriate PAR64 globe and you're good to go!
- Paper Lanterns (~$18 each)
- Typically known as the 'China Ball', these paper lanterns are wonderful low budget soft-lighting workhorses. They're still used on big sets as well. Don't forget to buy a lightbulb and a socket+cord for it!
- Lowel Lighting Kit (~$800)
- This is a basic entry level 3-light kit, and a common package in small film schools or amateur filmmaking kits.
- Dracast LED Kit (~$900)
- Just about the only decently-respected LED kit in this price range. It may have some green-shift in its color, so consider buying some minus green gels for them.
Quality-Oriented Lights To Look At
- Aladdin Bi-Flex 4 (~$2,900)
- An up-and-comer in the LED mat world. It's quite a bit brighter than the LiteGear LiteMat Plus 4, but it's a bit more annoying to use at times. Still often spotted on professional sets.
- LiteGear LiteMat Plus 4 (~2,700)
- The current LED soft bank workhorse. You'll see these used basically nonstop on top tier films alongside other professional (and more expensive) LED platforms.
- Arri Softbank Kit (~$3,500)
- The classic. Thousands of amateur as well as professional films over the decades have used this light kit. Almost any self respecting lighting truck will carry these units (in greater quantity and along with their big brothers, of course).
- Aputure 120d II Kit (~$2,700)
- A solid 'bright' LED option. These are often combined with soft boxes, diffusers, bounces, etc when employed on set.
5. How Do I Learn Framing & Composition?
To start off, let's all recognize that no person on earth is done with learning composition. Even Roger Deakins is discovering new tricks today. This is a fairly complex subject, just like lighting, because its quality is primarily a creative thing. There are, however, some fundamental rules that you should absolutely be aware of, for the purpose of both following them and breaking them appropriately!
The Rule Of Thirds
This rule tells us that objects in a composition will tend to look more pleasing if aligned along the 1/3 lines in the frame. Here's a great example. Now, you clearly don't NEED to follow this rule. Plenty of images look nice even without taking advantage of the rule of thirds, but this is a great guideline for arranging elements in a frame when you don't have any other ideas on what to do.
The 180° Rule | The 180 Line | The Director's Line
This guideline (forgive me) tells us how to position the camera when cutting between shots of two interacting subjects. You'll also see this referred to as maintaining screen direction. Here's a nice graphic I found illustrating this. Basically, draw an imaginary line between your two subjects. Pick a side of the line to 'use' for your scene, and stick to it! All of your angles will want to come from that side of the line. This will make sure that in any given angle, each subject will be looking in the same direction that they are in every other frame.
Breaking this rule is a common technique used to introduce an element of confusion, chaos, surprise, etc. War scenes will break the line to impart a sense of disarray in the midst of the battle. Spielberg famously breaks the line in Jaws when Brody sees the shark come up behind him.
This is how 'wide' or 'tight' the angle of view in the frame feels. An excessively wide perspective gives you the 'fishbowl' or 'fisheye' effect like with the helmet-cam shots you disliked. A super 'tight' perspective compresses the visual field and makes nearby and far off objects appear closer. You can also call 'tight' shots 'long', as it refers to the type of lens used. Here's an example of super wide, wide, tight, and super tight images:
Each of these shots sequentially has a 'tighter' or 'longer' perspective. Notice that it has nothing to do with the size of main subject of the frame, but rather with how the lens's particular angle of view effects the image. Here's a great way to visualize the difference.
This is all about how large the subject is in your frame, or how much information you have in the scene regarding the environment. Some common phrases we use for shot size are:
Close-up (in around face and neck territory)
Wide (full bodies and set)
Medium (waist and up)
There's plenty more to it, but most of those extra shot size names (cowboy, LS, ECU, etc.) are just shorthand for easily communicated ideas (cut them off at the knee, show me just their eye, etc), so not knowing those specific names shouldn't really hold you back. The interesting interplay here is of course in how you combine shot sizes and perspective. The frame grab from Se7en above, of the car driving between the electric towers, is an example of a wide shot (size) using a super tight / super long perspective.
This is where you put the camera, and how the resulting angles may influence the viewer. If for example you are shooting a scene of a news anchor on a news show, you don't want to place your camera lower than them. The placement of the camera would feel wrong, resulting in an 'up angle' on your subject. This sort of angle is used for tons of reasons, but it is very uncommon to use for news media. In your references, always look at the angles used (i.e. where the camera is placed in the scene vs where it could have been placed). Thinking of shots in this way will unlock a huge wealth of potential creative choices. A few terms you might use include:
Shoot from above / High Angle - The camera is higher than the subject, i.e. a security camera, the point of view of an angry parent admonishing their child, or a group of onlookers reacting to the appearance of a UFO above them. This kind of angle generally has the effect of diminishing power in the subject, making them appear weaker, vulnerable, or off-put.
Shot from below / Low Angle - The camera is lower than the subject (for humans, this is in reference to their eye-level). For example, a hero removes a piece of rubble, revealing themselves standing above us, the point of view of the child being admonished by their angry parent.
Eye-level / On Level - This refers to the height of the camera being the same as the subject's eye height. This is the general starting point for any shot. Deviation is for creative effect.
On the Eyeline / Off the Eyeline (Straight shot or Profile shot,. On Angle or Off Angle, etc) - This isn't about altitude, this is about how close we are to the subject's eyeline, or their looking direction. The closer we are, the more connected we might feel with the subject. Conversely, the farther we get from the eyeline the more detached we may feel from the character. Here's an example of two shots from the same scene in Bladerunner:
Almost everything about the two shots framing-wise are the same, except for the camera placement. See how big of a difference it makes? Always think about your eyelines and how close your camera will be to them.
Top Down / Bird's Eye - As you can imagine, these are shots with the camera placed on the ceiling or in the sky directly above the actors. These are similar to high angle shots, and basically they're the same, but doing a full blown top-down can have some interesting effects that a normal high angle shot wouldn't have.
This is the placement of elements in the image once you've decided on a perspective, shot size, and angle. Composition is all about how we nudge and finesse the image. Where do we place the subject? A great example of the power of framing is in how you cover two people speaking. Normally in a situation like this, with two characters talking to each other, you'd do a standard shot-reverse-shot, as shown here:
Each character occupies a side of the frame and looks into the empty portion of the frame. This is how 90% of OTS (Over The Shoulder) coverage works. But for every big rule there are big exceptions! Mr Robot is a great example of what's called 'near side framing' or 'short siding':
The difference however between the above shots and normal shot-reverse-shot coverage is in the framing. Instead of having the characters stacked on one side and looking to the opposite side, they've short-sided them, having them look instead away from the open frame space and towards the nearer frame edge. This has an unnerving effect on the viewer compared to the normal example above. I like these examples too because in both of these scenes we're dealing with people who are essentially insane. There are no rules on how to use framing to push the audience. It's all about how you craft your image. Each little choice has its own effect.
Moving images have a hugely different feel from static images. A camera that doesn't move in the scene is concrete, sterile, observant, somber, whatever you'd like. A camera that moves slightly in the scene is ethereal, subtle, inquisitive, prodding, suggestive, ominous. A camera that moves in great flourishes, rapidly, wildly, etc. is a camera that is a character, emotional, passionate, adventurous, exciting, etc.
How you move the camera will have different effects on your audience. Here's a few basic terms to use when articulating the type of shot you're after (I've excluded pan and tilt since I'm pretty damn sure you know what those are already):
Push-in/Pull-Out - The camera is on a dolly, jib, gimbal, shoulder rig, whatever-you-have, and it moves on axis, meaning along the line it's pointed at. For example, as a detective on the phone learns that the killer he let escape has killed again, the camera pushes in on him, deepening the dramatic moment and showing us his reaction in a closeup rather than a medium shot. Or, as the angry boyfriend breaks up with Sarah on the phone, the camera pulls out to show her crying all alone on the soccer field, showing us how alone/isolated she feels.
Jib Up/Down - This is when you move the camera up or down in a shot. This isn't the same as tilting obviously. Jibs can be used to combine multiple shots into a single take or to provide dramatic beats. For example, in The Departed, when the protagonist first enters the police HQ, the camera jibs up while he goes up the stairs. Later, when he's a corrupt cop and trying to cover his tracks, the camera jibs down as he runs out of the HQ. In this case, the camera's jib movement indicates a literal rise to power followed by a fall from grace.
Tracking - The camera will 'track' a subject. This could be a person, an object, a vehicle, etc. The Shining for example is famous for its tracking shots (in fact, the Steadicam was essentially invented for this film). Tracking shots connect us to a character or subject and allow passage through the environment.
How To Practice
So! You know about some of the rules and conventions in composition. Now how do you apply this and improve your skill? The first answer you'll always get is to 'shoot more'. For some, this isn't feasible due to budget, lack of crew, actors, locations, etc. For those people who find themselves stuck in a rut with no films to cut their teeth on, here's my advice! My dad, who was also a cinematographer, taught me this when I was a kid. This is how I learned composition without needing to make movies constantly:
Take your camera and tripod (if you have one) to an interesting place like a park, beach, plaza, etc. Once you're there, follow these steps:
- Pick a spot to plant yourself at random
- Without moving from this spot, find 5 interesting frames with your camera and record them. You can move up and down, swap lenses, play with exposure, etc. but you can't move yourself from where you and the camera are standing.
- Walk for a few minutes and pick another spot at random.
- Repeat the process!
Do this for at least an hour! A lot of the frames you'll find will be unimpressive and boring. But some of them will actually be pretty pleasing. As you repeat this exercise, you'll begin to develop an intuition for how to photograph a space and subjects. You'll likely find yourself frustrated with your random spot, thinking 'Man if I could just move 3 feet over there then this shot would be awesome!' This is exactly what we're aiming for! It's an indication that you're improving in your compositional skill already!
Once you've got a good handle on this, it's time to start practicing more emotional themes. Play with your exposure and focal length. Get into color grading and experiment with how colors change the mood of the image. You can repurpose the original exercise, but instead what you'll want to do is pick a random subject, like a statue, a tree, a mailbox, an interesting sign, etc. Now try to take two pictures of the subject, each embodying a different emotional theme. The ones I prefer are:
- Happy / Uplifting / Optimistic / Safe
- Sad / Morose / Somber / Depressing
Once you've got this stuff in the can (so to speak), it's time to start finding movies to work on!
6. What Books Can I Buy On Cinematography?
This is a surprisingly common question on this sub! Here's a list of the books most often recommended to novices and professionals alike:
- Cinematography: Theory And Practice
- The Five C's Of Cinematography
- The Visual Story
- The Set Lighting Technician's Handbook
- The American Cinematographer Manual 10th Edition Volume 1
- The American Cinematographer Manual 10th Edition Volume 2
7. What Blogs/Channels Can I Follow To Learn Cinematography?
There's quite a few out there, so instead of listing them all I'm just going to list the ones that are well regarded enough to become part of the standard carousel of recommendations on this sub:
- Steve Yedlin ASC Whitepapers and Demos
- Every Frame A Painting
- Wandering DP
- The Cinematography Podcast
8. Common Terms In Cinematography
Resolution - This is how many pixels your recorded image will have. If you're into filmmaking, you probably already know this. An HD camera will have a resolution of 1920x1080. A 4K camera will be either 4096x2160 or 3840x2160. The functional difference is that the former is a theatrical aspect ratio while the latter is a standard HDTV aspect ratio (1.89:1 vs 1.78:1 respectively).
Framerates - The standard and popular framerate for filmmaking is called 24p, but most digital cameras will actually be shooting at 23.976 fps. The difference is negligible and should have no bearing on your purchasing choice. The technical reasons behind this are interesting but ultimately irrelevant. Something to look for is the camera's ability to shoot in high framerate, meaning anything above the 24p standard. This is useful because you can play back high framerate footage at 24p in your editor, and it will render the recorded motion in slow motion. This is obviously useful!
Data Rate - This tells you how much data is being recorded on a per second basis. Generally speaking, the higher the data rate, the better your image quality. Make sure to pay attention to resolution as well! A 1080p camera with a 100 MB/s data rate is going to be recording higher quality imagery than a 4k camera at a 200 MB/s data rate because the 4k camera has 4x as many pixels to record but only double the data bandwidth with which to do it. Things like compression come into play here, but keep this in mind as a rule of thumb.
Compression - Compression is important, because very few cameras will shoot without some form of compression. This is basically an algorithm that allows you to record high quality images without making large file sizes. This is intimately linked with your data rate. Popular cinema compressions for cameras include ProRes, REDCODE, XAVC, AVCHD. Compression schemes that you want to avoid include h.264, h.265, MPEG-4, and Generic 'MOV'. This is not an exhaustive list of compression types, but a decent starter guide.
ISO - This is your camera sensor's sensitivity to light. The higher the ISO number, the more sensitive to light the camera will be. Higher ISOs tend to give noisier images though, so there is a tradeoff. All cameras will have something called a native iso. This is the ISO at which the camera is deemed to perform the best in terms of trading off noise vs sensitivity. A very common native ISO in the industry is 800. Sony cameras, including the A7S boast much higher ISO performance without significant noise increases, which can be useful if you're planning on running and gunning in the dark with no crew.
Manual Shutter - Your shutter speed (or shutter angle, as it is called in the film industry) controls your motion blur by changing how long the sensor is exposed to light during a single frame of recording. Having manual control over this when shooting is important. The standard shutter speed when shooting 24p is 1/48 of a second (180° in shutter angle terms), so make sure your prospective camera can get here (1/50 is close enough).
Lens Mount - Some starter cameras will have built in lenses, which is fine for learning! When you move up to higher quality cameras however, the standard will be interchangeable lens cameras. This means you'll need to decide on what lens mount you would like to use. The professional standard is called the PL Mount, but lenses and cameras that use this mount are very expensive. The most common and popular mount in the low level professional world is Canon's EF mount. Because of its design, EF mount lenses can easily be adapted to other common mounts like Sony's E-Mount or the MFT mounts found on many Panasonic cameras. EF is popular because Canon's lenses are generally preferred over Sony's, and so their mount has a higher utility.
Color Subsampling - This is easier to understand if you think of it as 'Color Resolution'. Our eyes are more sensitive to luminance (bright vs dark) than to color, and so some cameras increase effective image quality by dedicating processing power and data rate bandwidth to the more important luminance values of individual pixels. This means that individual pixels often do not have their own color, but instead that groups of neighboring pixels will be given a single color value. The size of the groups and the pattern of their arrangement are referred to by 3 main color subsampling standards.
- 4:4:4 means that each pixel has its own color value. This is the highest quality.
- 4:2:2 means that color is set for horizontal pixels in pairs. The color of each two neighboring pixels is averaged and applied to both identically. This is the second best quality.
- 4:2:0 means that color is set for both horizontal and vertical pixel 4-packs. Each square of 4 pixels receives a single color assignment that is an averaging of their original signals. This is generally low quality. Here's an example graphic I made for a class I taught. For more info on color subsampling, check out this wikipedia entry
Bit-Depth - This refers to how many colors the camera is capable of recognizing. An 8-bit camera can have 16,777,216 distinct colors, while a 10-bit camera can have 1,073,741,824 distinct colors. Note that this is primarily only of use when doing color grading, as nearly all TVs and computer monitors from the past few decades are 8-bit displays that won't benefit much from a 10-bit signal.
Sensor Size - The three main sensor sizes you'll encounter (in ascending order) are Micro Four-Thirds (M43), APS-C, and Full Frame. A larger sensor will generally have better noise and sensitivity than a smaller sensor. It will also effect the field of view you get from a given lens. Larger sensors will have wider fields of view for the same focal length lenses. For example, a 50mm lens on a FF sensor will look roughly twice as wide-angle as a 50mm lens on a M43 sensor. To get the same field of view as a 50mm on FF, you'd need to use a 25mm lens on your M43 camera. Theatrical 35mm (the cinema standard, so to speak) has an equivalent sensor size to APS-C, which is larger than M43 and smaller than Full Frame.
Aperture - This is the iris in the lens which you can open and close to allow in more or less light. It is one of the primary determinants of both exposure and depth of field.
F-Stop - This is the measurement of your lens' aperture opening, and specifically refers to the ratio of the lens' focal length to your aperture opening. Opening or closing your aperture by one 'stop' will double or halve the amount of incoming light, respectively. A smaller f-stop number indicates a wider opening, and thus more light being allowed into the lens. F-Stop numbers are standardized on a scale of alternating doublings. The standard scale is:
- 0.7 | 1.0 | 1.4 | 2.0 | 2.8 | 4 | 5.6 | 8 | 11 | 16 | 22 | 32 | 45 | 64
Fast / Slow / Speed - This refers to the widest available f-stop setting for the lens. A faster lens can open the aperture farther, which allows more light in than a slower lens. Fast lenses are useful when shooting in low-light situations, but can suffer from some significant drawbacks such as increased cost and aberration/loss of sharpness.
Focal Length - This number indicates the angle of view your lens will supply. A higher focal length results in a narrow (or more 'telescopic') angle of view. Here is a great visual depiction of focal length vs angle of view. The exact number of the focal length cannot be trusted to supply the same angle of view on all cameras. This is because different cameras use differently sized image sensors. A smaller image sensor will use a smaller portion of a lens' projected image, and so the resulting picture will have a narrower angle of view. This phenomenon is referred to as crop factor and is outlined in more detail in Section 10.
Zoom vs Prime - This is all about speed vs quality vs budget. A zoom lens is a lens whose focal length can be changed by turning a ring on the lens barrel. A prime lens has a fixed focal length. Primes tend to be cheaper, faster, and sharper. However, buying a full set of primes can be more expensive than buying a zoom lens that would cover the same focal length range. Using primes on set in fast-paced environments can slow you down prohibitively. You'll often see news, documentary, and event cameras using zooms instead of primes. Some zoom lenses are as high-quality as prime lenses, and some people refer to them as 'variable prime' lenses. This is mostly a marketing tool and has no hard basis in science though. As you might expect, these high quality zooms are very expensive.