The Basics of Using Speedlights

Let me start by making two important statements: 1. Flashes shouldn't be intimidating, and 2. Nobody should ever have to read their flash manual.

If you're anything like me, you probably started off feeling really excited to buy a speedlight, then immediately feeling really lost when you finally did.  I started with an ignorant and sordid love affair with pocket strobes (aka. Speedlights - or "Speedlites," for our Canon friends). I mean, sure, I understood ratios and the fundamentals of light theory, but when it came to understanding how to use a flash, the modes, their purposes, the terminology, and the technical elements I was completely lost. So I spent years alternating between TTL and straight-up guessing through project after project; with absolutely no idea how flashes actually worked, what the features and functions were, nor what made one better than another. 

Two Nikon Speedlight SB-910 flashes with diffusers.

One day though, I'd had enough.  I was tired of having a creative concept – with a clear vision of the final product, and find myself helplessly fighting my own equipment to do the most basic of things.  It was amazing the lengths I'd go to avoid actually learning how to use my Speedlight, just to inevitably either get completely lucky, compromise my standards, or simply walk away from it.

This week we clear all that stuff up.  Nobody should have to read their flash manual.  I'm convinced that they're inhuman drivel, presumably designed by engineers for other engineers.  Instead just read this, and if you have any questions that it doesn't clear up then consult the specific page of your manual that pertains to that question (It's better than reading the whole thing).  Flashes shouldn't be intimidating, so I'm going to lay it out in the easiest to understand way I can.


Here's where you'll find a bunch of terms that I pretended to understand when I first got a Speedlight.  The thing is, if I put it all at the top then you'd be scrolling for miles before you got to the meat of the article.  I've put all the necessary terminology at the very bottom of this post.  Terminology is important, so brush up on it as it will help you while reading future articles.  I've kept it as brief as I could, and as simple to understand as possible, so when you need to understand something just scroll to the bottom.  Or click here.

Let's get to it!


TTL (a.k.a. "iTTL," for us Nikonians, and, "E-TTL," for our Canon cousins)

This refers to the technology built into modern cameras where a brief burst of light emits from the flash microseconds before the actual shot so that the camera can evaluate the exposure Through The Lens (TTL).  Modern DSLR's are so quick that you won't notice the first flash separate from the actual exposure.  This mode is fantastic for nailing the average shot in average lighting, but tends not to understand if you're artistically aiming for some dramatic effects or out of the ordinary environments.  In those cases you may want to adjust your flash compensation (see below) or switch to a more manual mode.

Auto Aperature


Distance Priority

Back in the days of film people routinely used charts to estimate the ideal flash strength based on camera settings, environmental conditions, and the distance to their subject.  Distance priority is...


Repeating Flash



This mode sets your flash to fire when it sees any quick bursts of light.  You set the power level manually, point it where you need it to flash, and it flashes when it sees another flash go off.  It's great if you're using unconventional lighting setups (like using flashes that are from other brands, or a built-in flash that isn't designed for commanding a Speedlight).  However it's not so great to use at events like weddings where other people may trigger it by using their own flashes - which kills your batteries in record time.

Manual - This mode has no safety wheels.  You'll be setting the zoom, the power, everything.  Play here often, but only when there's no pressing emergency.  Much like the manual mode of your camera the more you play here the better you'll get, and eventually you'll never look back.  The power outputs are displayed (for Nikon) in fractions (eg. 1/1, 1/2, 1/4, ... 1/128) where 1/1 is the strongest output the flash is capable of, and obviously it goes down from there.  Remember though that your flash uses power cells that are filled by your batteries; think of the cells like a bucket, the more you empty them the longer it will take to fill up again to full (a.k.a. "Recycle Time" which we'll elaborate on later).

Flash/Strobe vs. Ambient

This one's easy to understand.  Think of the term, "Ambient," as another way of saying, "constant."  If the light is constantly on at the same level, then it's an ambient light source.  Examples of this would be the sun, lamps, ceiling lights, etc., basically anything that doesn't get brighter in a hurry when you're shooting a photo.  The converse, anything that gets brighter in response to your camera triggering it, is a flash.

"Flash" vs. "Strobe"

This part is confusing because so many people use the terms interchangeably, and where I may define one in a certain manner, someone else will define it with a different term.   Regardless of the terminology, the difference boils down to how much power they pack.

When you hear the term, "flash," generally people are referring to a pocket strobe such as Nikon's SB-910, SB-800, or Canon's 600EX, 430EX III, etc., or the pop-up/built-in flash that comes with the camera.  Each of those are relatively low in power in comparison to what is generally referred to as a, "strobe."  A strobe on the other hand is generally the term used when referring to the more powerful flashes that one would find in studio use, such as the Profoto B1/B2/D1 strobes, a Paul C. Buff Einstein E640, or the Elinchrom D-Lite series strobes.

Most flashes will have the option of connecting to your camera via the hot shoe, whereas strobes will almost always be a form of off-camera light.  However, both strobes and flashes routinely do offer on-camera options like remotes to trigger the flash/strobe units from a distance and even offer some advanced features like TTL and High Speed Sync.  An example of this would be something like Canon's ST-E2, or (my personal favourite) Profoto's Air Remote TTL-N which I use to control my Profoto B1 Air 500's and my D1 1000, or the Elinchrom EL-Skyport.  Most flashes offer AA options for power, or smaller battery packs, also.  Whereas strobes tend to have more sizeable batteries/power packs, or have direct AC options for you to plug it into a wall.

Pros of Flash/Cons of Strobe:

  • Size - They are much smaller and generally fit just about anywhere, in any sized camera bag, and they are light enough to mount onto most things with a Gorillapod or a Bogen Clamp.  Most conveniently they also fit easily onto your camera's hot shoe.
  • Power Supply - Most of these take AA batteries, a power supply that you can find pretty much everywhere, and in a pinch you could even steal from a television remote, etc.  Because of the reduced size of the power supply you can generally carry these things into any environment, which becomes particularly convenient in environments without power outlets (where many strobes can't go).
  • Price - Flashes are generally much cheaper than studio strobes.  As a result you can purchase more flashes for the same amount of money and get similar/equal results.
  • Design - Creativity favours flashes strongly in some areas.  The convenient small size and wireless nature allow you to tuck flashes away in spots where a studio strobe simply wouldn't fit.  The wireless triggering allow photographers to set up groups of flashes to fire at different intensities.  Yes, this may also be accomplished with strobes, but in many instances the manufacturers program functions to control and exploit these features right into their camera bodies, whereas strobes sometimes do not offer features like TTL and High Speed Sync options.  Plus, no wires means less tripping.
  • Versatility - Flashes can be used in lieu of studio strobes in a studio, whereas studio strobes often are too powerful for places where flashes would be fine.
  • Assistance - Flashes often feature AutoFocus Illuminator/AF-Assist which cast infrared grids onto your subject to help your camera find sharp lines to focus on.  While Strobes offer modelling light options, just because you have light doesn't mean you'll always have enough contrast/detail for your camera to lock onto focus.  This is a big win for flashes.

Cons of Flash/Pros of Strobe:

  • Power - Flashes often can't hold a candle to strobes when it comes to sheer power output.  This means that it will take more flashes to be triggered simultaneously when it comes to matching, which can be a complicated and inconsistent process.  
    Also, batteries such as AA's and AAA's tend to run out of power quickly in many environments.  Strobes, being plugged into the wall or featuring bigger batteries, tend to last much longer/indefinitely.
  • Refresh Rates - The refresh rate (or "cycle time") between flashes is substantially higher than many strobes.  There are exceptions, but generally strobes win this category by a landslide.
  • Modelling Lights - Most strobes have modelling light options, whereas the majority of flashes do not.  Though some flashes do offer modelling lights, often they're not constantly on, which can be a bit fickle when you're trying to see where the shadows are going to fall and when trying to adjust lighting/subject/camera position for composition.
  • Accessories - Flashes have a number of fantastic accessories, but generally they're limited to what a single flash would be capable of using.  That means though you can group flashes to match the power output of a strobe, often accessories such as softboxes, grids, etc. will not be designed to accommodate more than one flash.  Strobes win by a landslide on this one too.
  • Hard Light - Because of the relatively small nature of the light's face, flashes tend to cast harder light than a strobe, and need to either be bounced or diffused to cast soft light.  

Light Intensity


Bouncing and Diffusing


Red Eye

This is a direct result of flash bouncing off of the

Lightroom and Photoshop have great simple to use ways of resolving this problem, but the easiest way of avoiding it is to simply not have it in the first place.  Getting the light to come at the subject from any other angle than straight from the camera ensures that you should not have any issues with red eye. All that stuff I talked about earlier with Bouncing and Radio Triggers,


Quality of Light


Front Curtain

Rear Curtain

Slow Syncing (“Syncro-sun”)

High Speed Sync

Commanding Flashes (IR)

Master/Commander and Grouping Flashes

Radio Triggers

Power Output (Guide Number)

Flash Duration


Terminology - For Reals this Time

AF Assist (aka. AutoFocus Illuminator) - This is an infrared grid that is projected onto your subject by your Speedlight that assists in your camera attaining focus on.  It makes focus much easier to achieve in subjects where there are no sharp contrasts or defined textures.  When used through your Speedlight the great part about this feature is that it can be set to function regardless of whether or not the flash actually fires.  This way if you choose to shoot for more of a 'natural light' look, you can benefit from focus assistance. 

Ambient Light - Any light that is constantly on, that is not triggered by your camera. (ie: Sun, Ceiling Light, Candle)

Barn Doors - A light modifier that is attached to the light/strobe/flash which directs the light by the use of adjustable opaque flaps.

Bounce Card - A small (generally retracting) card that is built into flashes which can give a measure of fill light, or act as a "catch light" to produce an appealing light reflection in the subject's eyes.

Bounce Flash - The act of directing your flash/strobe towards a surface that is not your subject, so that the light will reflect off of that surface and "bounce" onto your subject.  It is often used to make the source of light bigger relative to the subject, or to carry over some of the colour properties of the object/surface.  An example of this would be directing your flash at a wall so that it bounces off of the wall and onto the subject.  Though the flash would be emitting from a smaller head, it would spread out before hitting the wall, and then the wall would have a larger spot to reflect from creating a relatively larger light source shining onto the subject and thus "softer" light.

An example of using this to carry the colour properties would be to bounce off of a coloured wall in order to add a hint of that colour to the subject. Ie. If a subject is standing next to a yellow wall, and you want the subject to look warmer on the colour temperature scale, then you could bounce the flash off of the yellow wall, casting some of the warm yellow colour onto them.  (Yes, I understand that in such an instance the colour doesn't technically reflect, other colours get absorbed, but this isn't a theory of light post, and for all intents and purposes this will make sense to beginners)

Bracket - This is the process of shooting multiple shots with different exposures, for example one shot purposefully underexposed, and another shot purposefully overexposed.  This way in post processing the photographer would have options to potentially choose from if the exposure wouldn't suffice for their purposes.

Creative Lighting System

Direct Flash


Fill Flash (a.k.a Secondary)


Flash Compensation

Flash Meter



Guide Number

Hair Light

High Speed Sync

Hot Shoe

Main Flash (a.k.a. Primary or "Key")


NiMH (Nickel Metal Hydride)

Kicker (a.k.a. Separation Light)

PC Terminal

Radio Trigger (a.k.a. Pocketwizard)



Ring Light

Strobe (a.k.a. Pocket Flash)

Sync Cord

TTL (a.k.a. iTTL or ETTL)