Learn How to Shoot in Manual Mode Pt.1: Aperture
Why shoot in manual mode?
If you’re new to photography or have just upgraded your camera to a DSLR or mirrorless system then you may be looking at the daunting “M” on your mode dial. You switch to it. There are all these numbers at the bottom of the screen, the viewfinder is dark or blown out, you panic and flip back to automatic mode hoping to never relive the trauma. I know this from my own personal experience picking up my first DSLR back in 2012. Truth be told, I didn’t touch manual mode until 2014. Why? Because automatic mode “just worked.”
Concepts like depth of field, motion blur, image noise, etc. never crossed my mind. I’d just capture my image using the cameras internal sorcery and thought “Presto, got it.” Although my eye for composition improved over this time, my technical knowledge was still lacking. I had to understand what those “numbers at the bottom of the screen” meant. Editing could only do so much, I had to know how to “get it right” in-camera.
The Trinity
Aperture. Shutter Speed. ISO. These are the three settings to understand in order to be a successful manual shooter. These terms may sound foreign now, but once you learn them you’ll be excited to use them to create better, more controlled, images.
Aperture
Think of the lens as a medium to focus light, which projects the focused light on to the camera’s image sensor, which then digitally interprets the light into information on your SD card. How much of that light you allow in to hit your sensor is (in part) a function of your lenses aperture. In video, this would be referred to as the iris. I like to think of the aperture as a literal iris (or pupil), as in the ones in your very own eyes. When you enter a dark room your pupils expand and open up in an attempt to receive more light. If you exit that dark room into the high noon sun your pupils would then contract and let in less light. Your eyes are like cameras, adjusting their exposure in various light situations.
Your lens’ aperture has blades that contract and expand from being wide open, to closed down. Think of shining light through an open circle, then filling in that circle to have a just a small hole in the center. Which one would let through more light?
The lowest numbered aperture your lens is capable of means it’s iris blades are fully open. This is the maximum amount of light possible for the lens to gather. The higher the number, the more closed the iris blades get until they only let in a pinhole of light. These settings affect more than just light, but the depth of field (DOF) of your final image as well.
Important Note: the F before your aperture value stands for “F-Stop”.
This was always the trickiest setting for me. The correlation between the values and brightness are inverse. I like to think of it in terms of the situations you would use them in.
Available Light = Aperture Setting
Low Light (Dark) = Low Aperture Value
High Light (Bright) = High Aperture Value
Think of this more as a pneumonic and not as a rule that isn’t meant to be broken. You can adjust your ISO and shutter speed settings to allow you to use a low aperture value in situations with lots of light (like a sunny day). The above diagram covers the two extremes of the lens’ range. Sitting between it’s highest and lowest aperture value are a series of F-stops.
F-Stop, Drop and Roll
F-stop (short for Focal-stop) is a measurement of light. Essentially, you either cut your light in half or you double it. This applies to full stops of light, most cameras have the ability to adjust your aperture in 1/3 stop increments. However, let’s just think in terms of full stops.
When switching between full F-stop aperture values we either double the amount of available light or we cut it in half. If your scene is too dark, open up and double the light, if it’s too bright then stop it down and half the light. As I mentioned before these are FULL stops. You will be able to control your aperture in 1/2 and 1/3 stop increments on most modern cameras.
Focal Length and DOF
Depth of Field: Open apertures produce a smaller focal plane. Keep your aperture in mind when deciding what parts of your scene you want in focus. Sometimes wide open isn’t always best!
Not only is the luminance (or brightness) of your image effected by your F-stop but your field of focus changes as you modify your aperture. At F/1.4 you would have an extremely shallow depth of field. This means your focal plane is very narrow. Your selected focus point will be sharp with a blurred foreground and background. Think of iPhone’s portrait mode, how it separates you from the background by blurring it (via advanced image processing). That’s what you can achieve optically with a wide open aperture, however how dramatic this effect is will be based on your lens’ focal length and your distance from your subject of focus.
Short Story: Focal Length
Your focal length dictates your field of view. A lens’ focal length is measured in millimeters. The smaller the number the wider the field of view (FOV)
e.g. 15mm Focal Length = 100° (wide) Horizontal FOV | Think of the .5x mode on iPhone 11 or a GoPro
85mm Focal Length = 24° (tight) Horizontal FOV | Think “Zoomed In”
BOTTTOM LINE: MORE MILLIMETERS = MORE ZOOM
In order to capture a picture of your subject in a medium close up (from the chest to a bit above the head) you would have to change your perspective depending on your lens’ focal length. 15mm yields a very wide FOV, so to fill the frame with your subject, you’d have be very close! Where as if you stayed at that distance and swapped to an 85mm lens, you’d see just their nose.
An 85mm lens exposed at f/1.4 would have significantly more dramatic depth than a 15mm lens exposed at the same F-stop. Because your FOV is more narrow, it’s likely that you’ll have to be quite far from your subject. That space between your camera and subject as well as the distance to the background are important for how much visible shallow depth you’ll achieve. I’ll have a separate post strictly on this subject in the near future.
LONGER FOCAL LENGTH = LONGER REACH = MORE PERSPECTIVE COMPRESSION AKA DRAMATIC SHALLOW DOF
Have You Met Your Lens?
What do these numbers mean?
Quick Things To Know About Your Lens
Aperture: Your maximum F-Stop value. The number is usually found on the front element of the lens or on the side and is preceded by a “1:X” X being the most open F-stop of the lens. e.g. 1:2.8 means the lens maximum aperture is F/2.8 You’ll see some standard kit lens zooms with a variable aperture throughout the focal lengths, e.g. 1:3.5-5.6 meaning at it’s widest focal length it’s f/3.5 and at it’s most telephoto end (fully zoomed) it’s an f/5.6
Focal Length: Usually printed in the same place as the aperture in millimeters. There are two primary categories of lenses: Primes (fixed focal length) and Zooms (variable focal length) so you’ll either see a set number or a range between two numbers. e.g. 35mm for a prime or 70-200mm for a zoom lens.
Minimum Focus Distance (MFD): This is a very important characteristic of any lens. The minimal focus distance is exactly how it sounds, it’s the closest distance to a subject that the lens can achieve focus. Wider and normal focal ranges tend to have closer MFD (.9 meters) while telephoto ranges tend to have further MFD (3 meters) so it’s good to know your lenses MFD and plan accordingly with your space. This is usually printed somewhere on the barrel of your lens, measured in meters and/or feet. If you see a flower emblem printed next to the specification then that indicates it’s a Macro lens, meanings it can achieve focus very close to your subject.
Image Stabilization: Over the years image stabilization has become a standard in most mid to high end lenses. Is it necessary? No. Useful? Absolutely. Good image stabilization can allow you to “bend the rules” of photography. Allowing you to gather more light and shooting at a lower shutter, without sweating the blurry results of the “camera shakes” is definitely a luxury.
Front Element Thread Size: This is marked on the front element of your lens and is important for you to know in the event that you want to use filters. Filters can be very useful in modifying the light coming through your lens. Thread sizes vary and also measured in millimeters, marked with a diameter symbol (e.g. Ø77mm or Ø52mm) If you plan on shooting video alongside photos, I suggest looking into Neutral Density Filters (ND). These effectively dim the light coming through your lens, like sunglasses, allowing you to use wider apertures in bright situations.
