Nick Carver Photography Blog

Photography Tips, Tutorials, & Videos

CONTACT NICK

Digital Photography Tips: Why Shutter Priority Mode is Useless

Skill Level: Intermediate

Aperture Priority ModeYou know all those shooting modes on top of your camera? Well here's the deal: most of them are useless. In fact, once you know what you're doing, pretty much all but 2 of them are useless. Once you get a good handle on shutter speed, aperture, and ISO, the only modes you need are Aperture Priority Mode ("Av" or "A" mode) and Manual Mode ("M"). All the full auto and "Scene" modes don't give you enough control, so the creative decisions are in your camera's hands, not yours. That's not good. Same with Program Mode ("P"). Sure, you can control the ISO and the exposure compensation, which is a huge improvement over full auto, but the camera is still taking care of the all-important aperture and shutter.

So then what about Shutter Priority Mode ("Tv" or "S" mode)? Yep, that's useless, too.

Okay, okay. This is where some advanced amateurs throw up their hands in protest. "How could shutter priority mode be useless? What about when you want to control the shutter? How about when you want to freeze action with a fast shutter or get that silky water looks with a slow shutter? You need to be able to select the exact shutter speed you want."

I hear what you're saying, but Shutter Priority Mode is still useless.

So here's the deal with Shutter Priority Mode...it looks good on paper and it's easy to make it sound useful, but it just isn't. In fact, camera makers know Shutter Priority Mode is useless. That's why they didn't even put it in cameras until quite a long time after they invented Aperture Priority Mode. They had the technology to do it once they invented Aperture Priority Mode, but they just didn't put it in their cameras because they knew it wasn't a logical way to adjust your settings. This is also why you'll rarely find a pro using Shutter Priority Mode.

Alright, quick disclaimer: I'm sure there are one or two really rare and ultra-specific exceptions where using Shutter Priority Mode would work just fine. But I promise you that in these rare instances you could just as easily get your settings in Aperture Priority Mode, and these instances are so uncommon that it's not even worth addressing. Actually, I can't even think of an example, so that should tell you something.

So let's look at why this mode is so useless:

1. The shutter doesn't need to be that specific

Here's the number one reason Shutter Priority Mode is useless: the shutter speed just never really needs to be that specific. It's not logical to put in an exact shutter speed in 99.9% of situations because there's just no reason for the shutter speed to be super specific. Often times the shutter speed can fluctuate hugely on a given subject and the picture will look no different.

Let's consider a simple landscape. You're on a tripod photographing a mountain. You're not going anywhere and the mountain's not going anywhere, so it doesn't matter if your shutter speed is 1/8000 or 30 seconds - nothing's moving and so nothing will look different.

Alright that's an easy one, but what about sports?

Same deal. Let's say you're photographing a soccer game and you've decided that 1/1000 will freeze your athletes. Well what happens if you use 1/2000 instead? Of course, they'll be just as frozen. And what if you use 1/4000? Yep, still frozen. 1/8000? Frozen.

Okay, so then it's not that you need 1/1000, you need 1/1000 or faster. You don't need an exact shutter speed, you need a range of shutter speeds.

Shutter Priority Mode is Useless

This was taken at 1/2000, but it would
look no different at 1/1000 or 1/4000

How about doing some portraits with a 50mm lens? Well, your model is posing nice and still for you, so all you need to freeze is your camera shake. On a 50mm lens, camera shake is frozen at 1/50 or faster. So again, what happens if you use 1/100 or 1/250 or 1/4000 instead? Everything will be just as frozen. You don't need 1/50, you need 1/50 or faster.

See the thing with motion and the shutter speed is it's just like water. Once it hits a certain limit, it's frozen. Once water hits 32-degrees Fahrenheit, it freezes. It's not any more frozen at 10-degrees or 5-degrees or -20-degrees. Once it's frozen, it's frozen - same goes for moving subjects and the shutter speed.

Then what about when you want to blur motion, like getting that silky effect on a waterfall? Same deal here. The waterfall will look completely silky at about 1" (1 second). So what if you use 2"? Still silky. What if you use 10"? Yep, still silky. Once motion is frozen, it's frozen, and once it's moving, it's moving.

Shutter Priority Mode is Useless

This was taken at 2.5 seconds, but it
would look no different at 1" or 10"

Even when you're going for specific effect on the motion, like trying to get some motion blur, but not too much motion blur. In that case, it still doesn't need to be exact. Typically a range of shutter speeds will create virtually the exact same effect on motion blur.

Shutter Priority Mode is Useless

Like in this photo of a helicopter, I want some motion in the blades, but not too much. I used a shutter speed of 1/160. But the motion would have looked nearly identical at shutter speeds from 1/80 to 1/250A minor change in the shutter speed equates to a minor change in how motion is rendered.

2. The aperture is too important to let the camera control

If you're controlling the shutter speed as you would in Shutter Priority Mode, then the camera is controlling the aperture. The aperture affects depth of field (background blur). So as light fluctuates and the camera adjusts the aperture to compensate, the background blur on your images will fluctuate, too.

Let's consider the soccer game example again. And let's say I put in a shutter speed of 1/1000 using Shutter Priority Mode. As I point the camera up the field, my camera chooses an aperture of f/4.5. Then I follow the action down the field where the light is a little different because of the angle of the sun. In this new light, my camera chooses f/8. F/4.5 creates a smaller DOF than f/8, so now all my pictures pointed up the field have blurrier backgrounds than my pictures pointed downfield.

But let's try the same situation in Aperture Priority Mode instead. I decide that I want a blurry background, so I put in f/4.5. When I point my camera upfield, wouldn't you know it, my shutter comes out to 1/1000. Good - I need 1/1000 or faster to freeze the action. Okay, now I follow the action downfield again to the different light. My aperture won't jump to f/8 this time because I have it locked in at f/4.5. Instead, my camera adjusts the shutter for the changing light, bringing it up to 1/3200. No problem there, 1/3200 will freeze the action just as good as 1/1000. So the result is a consistent background blur (because the aperture didn't change) and consistently frozen motion (because the shutter speed stayed above my threshold of 1/1000).

By controlling the aperture directly in Aperture Priority Mode, you're not leaving the all-important DOF up to the camera. Background blur is simply too important to let the camera control! Because after all, a small change in the aperture can dramatically alter the photo, but an identical change in the shutter speed often results in no noticeable difference in the image.

3. The shutter is less likely to hit a "dead end"

Let's look at the entire range of available shutter speeds:

30   25   20   15   13   10   8   6   5   4   3.2   2.5   2   1.6   1.3   1   0.8   0.6   0.5   0.4   0.3   1/4   1/5   1/6   1/8   1/10   1/13   1/15   1/20   1/25   1/30   1/40   1/50   1/60   1/80   1/100   1/125   1/160   1/200   1/250   1/320   1/400   1/500   1/640   1/800   1/1000   1/1250   1/1600   1/2000   1/2500   1/3200   1/4000   1/5000   1/6400   1/8000

Now let's look at the entire range of available apertures on a typical pro lens:

f/2.8   f/3.2   f/3.5   f/4   f/4.5   f/5   f/5.6   f/6.3   f/7.1   f/8   f/9   f/10
f/11   f/13   f/14   f/16   f/18   f/20   f/22

You can see that there are many more shutter speeds available than apertures. But in every situation you take pictures, there needs to be an aperture to match your shutter speed. So here's an all-too-common problem with Shutter Priority Mode: often times you'll pick a shutter speed that has no matching aperture. In other words, you've selected a shutter speed that is too fast (lets in too little light) or too slow (lets in too much light) and there is simply no aperture to match it. The aperture hits a dead end.

The camera warns you when this happens, by the way. If you choose a shutter speed that's too fast or too slow for the apertures to match it, the camera will flash the aperture number at you or indicate "HI" (for "high light") or "LO" (for "Low Light") where the aperture number should be. This is the camera telling you that it's trying to find an aperture to match your shutter, but it hit a dead end and can't go any further. As a result, your picture is going to come out too bright or too dark.

But if you shoot in Aperture Priority Mode instead, you're controlling the variable with fewer options (the aperture). And so the camera will pretty much always be able to find a shutter speed to match your selection on the aperture. In other words, the camera won't hit a dead end because there are just so many shutter speeds available.

4. You have just as much control over the shutter in Aperture Priority Mode

This is where beginners ask, "Then what about those times when the shutter speed is your top priority, like when shooting sports or wildlife? Shouldn't you be in the mode where you can control the shutter so that you can ensure it's correct?"

No. You don't need to control the shutter speed directly in order to make it come out right. Sure, Aperture Priority Mode doesn't let you control the shutter speed directly, but that doesn't mean you can't control the shutter speed (wow, man, that's deep).

Here's what I mean: so long as you're in control 2 of the 3 exposure variables (shutter speed, aperture, and ISO), you essentially have control of all 3. With 2/3 control, the camera will be forced into a corner on the third and you can get what you want out of it. So, if you don't like your shutter speed in Aperture Priority Mode, just do what you would do in any mode: change the ISO and/or the aperture. Need a faster shutter? Just raise the ISO or open the aperture - that's what's going to have to happen anyway, regardless or what mode you're in.

So bottom line is this: don't bother with Shutter Priority Mode unless you have a really good reason to do so. Aperture Priority Mode is a much more useful mode and will afford you all the same control over the shutter as Shutter Priority Mode. And don't let anyone try to convince you of the usefulness of Shutter Priority Mode...that's a red flag that they might not know what they're talking about.

To learn more about shutter speed, aperture, ISO, exposure, and much more, check out my Introduction to DSLR Photography Online Course for beginners and my Understanding Exposure for Beginners Photography Class in Orange County, CA.

Digital Photography Tips: Auto White Balance Kills Color

View on YouTube to see this photography tip in HD

Photography Tips: Don't Use Auto White BalanceSkill Level: Intermediate

I've had a lot of students ask me lately why the colors in their photos are coming out inaccurate, so I thought it would be fitting to post a digital photography tip all about auto white balance. I'm marking this photography tip as "Skill Level: Intermediate" because I'm going to assume you already know what white balance does and how to control it. And if you don't know what it is, I offer group classes and online courses that can get you up to speed.

The topic of this photography tip pertains specifically to auto white balance - often abbreviated "AWB." The auto white balance setting is like many automatic functions on your camera: it works well enough a lot of the time, but it can really screw things up if you're not paying attention.

Auto white balance works like this: it looks at the photo you're taking and it tries to determine if there's too much of one color family. If it sees too much of one color, it floods the picture with the opposite color to try and cancel it out.

So let's say you have some incandescent lighting overhead when you're taking a picture of your family. Well, incandescent lighting is throwing out a ton of yellow-orange light. So auto white balance sees the excessive warm tones and says, "That's way too much yellow-orange," and so it floods the picture with blue to cancel it out. This is assuming auto white balance is doing a good job. Many cameras don't add quite enough blue in this scenario and leave your indoor shots looking too yellow.

That's the basic concept of auto white balance - if the camera sees too much of one color, it deems that an "unwanted color cast" and then tries to eliminate it by adding the opposite color. This approach to eliminating unwanted color casts is good enough for many pictures. And when you have to shoot quick, good enough is good enough.

But here's the problem with auto white balance...how could it possibly know the difference between a color cast you want and a color cast you don't want? The yellow color cast from incandescent lighting is a color cast you don't want, but the yellow color cast from fall leaves is. The camera can't make the distinction between these two. Your camera is dumb! It doesn't even know what it's looking at. It just sees too much yellow, regardless of where that yellow is coming from.

So when you shoot fall leaves on auto white balance, what ends up happening is this; the camera's auto white balance sees a bunch of yellow and it says, "Well, that's way too much yellow. Must be a color cast my photographer doesn't want," and so it floods the picture with blue to tone down the yellow. The result is fall color that isn't so fall color-y anymore.

Here are some examples:

Photography Tips: Auto White Balance

 AWB (above) vs. the accurate shade setting (below)

Photography Tips: Auto White Balance

 

 

Photography Tips: Auto White Balance

  AWB (above) vs. the accurate cloudy setting (below)

Photography Tips: Auto White Balance

 

 

Photography Tips: Auto White Balance

 AWB (above) vs. the accurate daylight setting (below)

Photography Tips: Auto White Balance

 

Same thing on a sunset. The auto white balance sees a bunch of warm tones from the setting sun, assumes you don't want them, and then floods the picture with blue to tone it down.

Photography Tips: Auto White Balance

 AWB (above) vs. the accurate daylight setting (below)

Photography Tips: Auto White Balance

As you can see, auto white balance can really destroy colors in your photos. That leads to my very simple digital photography tip: when photographing subjects with strong color casts, don't use auto white balance. Instead, use the appropriate white balance setting (daylight setting in daylight, shade in shade, etc) or adjust it yourself in the computer by shooting RAW files. I used Adobe Lightroom to adjust the white balance on my RAW files. It's a great program and I highly recommend it to all shooters. Get a great price on Adobe Lightroom at B&H.

Use auto white balance when you need to shoot quick and you're not too worried about the colors being perfect. But when the colors have to be just right, don't use AWB...it may just tone down the colors too much.

Why the Exposure Triangle is Completely Useless

Understanding Exposure: Why the Exposure Triangle method is complete BS

The "exposure triangle" is a common tool for teaching beginners about exposure. But here's the truth about the exposure triangle: it's a terrible learning tool that is more likely to harm than help beginner photographers. I believe this tool is adopted by teachers who actually aren't that good at teaching a simple concept. They can't communicate shutter speed, aperture, ISO, and exposure in an effective way, so they teach via this "learning trick."

The Problem with The Exposure Triangle

Take it from someone who teaches photography for a living: the exposure triangle makes the simple concept of exposure seem much more complicated than it is. I know exposure, shutter speed, aperture, and ISO better than I know myself and I can barely make sense of the exposure triangle. I'm serious. It's comical how unnecessarily complicated it is. It's like watching one of those Rube Goldberg machines that turns the simple task of toasting bread into a thousand-step process.

But aside from the fact that it's overly complicated, the inherent problem with the exposure triangle is that it relies on memorization rather than understanding. You are expected to visualize a diagram with shutter speed, aperture, and ISO labeled at each respective corner, trying to remember which corner means more light, which one means less light, which side deals with motion blur, which side deals with depth of field... Unless you have a photographic memory, you're going to have to carry along an exposure triangle cheat sheet for reference.

So then what's wrong with carrying around a cheat sheet? Well, taking pictures with the help of a cheat sheet is like trying to ask a girl out on a date using a pre-written script - it'll work until she says something you weren't prepared for. The "cheat sheet" method of shooting is too slow and too inflexible. You have to be able to think fast, think on your feet, and adapt to situations quickly. An exposure triangle cheat sheet can't do that.

The Better Way to Think About Exposure

The way I teach my students about exposure doesn't rely on memory tricks like the exposure triangle because learning by memorization doesn't work. Memories can't be trusted. But if you understand how something works, then you'll almost never forget it and the whole process becomes easy. So let's talk about how to understand exposure so that we no longer need to rely on memory.

For now, let's ignore all the numbers connected to shutter speed, aperture, and ISO. The numbers are secondary, first you must understand the mechanics of exposure. If you think about the mechanics of how an exposure is made, then you'll be able to problem solve any exposure situation - no need for an exposure triangle cheat sheet. The numbers will follow.

How Exposure Works

Creating an exposure is simply the process of recording light on a photosensitive material. Traditionally that light was recorded on film, now digital cameras record light with a photo-sensitive computer chip called the "image sensor." Getting a "correct exposure" means that you recorded the correct amount of light - not too much, not too little. If you didn't record enough light, the picture would be "underexposed" or "too dark." If you recorded too much light, the picture would be "overexposed" or "too bright."

Light is made up of particles just like anything else. It's almost like water, except we can't touch it or feel it. Getting the right amount of light to your sensor is a little like getting the right amount of water to a sponge. So let's forget light for a minute. Let's talk about water.

Let's say I have a big sponge that I want to saturate with exactly 20 ounces of water from a garden hose. I can't have too much or too little - it needs to have just the right amount of water in it. And let's say I have to turn on my garden hose for exactly 1 second to get my 20 ounces. Simple enough: Garden hose turned on for 1 second and I get my 20 ounces.

Well what's going to happen if I switch out my garden hose for a fire hose? Will I have to leave my faucet on for longer or shorter now that I have a bigger hose?

Shorter. Duh. It's a bigger hose, so more water comes out, so I won't need to turn it on so long. Now how did you figure this out? Did you refer to your "water, hose, faucet triangle" on your "water triangle cheat sheet"? No, you just thought about it. This is how you should think with light and exposure. Don't rely on an exposure triangle, just think about the flow of light to your image sensor. The sensor in the back of your camera - the thing that creates the image - works just like a sponge, but instead of soaking up water, it soaks up light.

How exposure works: DSLR Camera mirror

Above is an image looking into the camera with the lens off. This is the camera "at rest" meaning it's not taking a picture right now. You'll notice there's a mirror there. That allows you to see what the lens sees before taking the picture. 

Below is an image looking into the camera while it's taking a picture. The green box in the back is the image sensor. That's what collects light (like a sponge) and turns it into an image. The mirror has to move up out of the way so the sensor can soak up the light. When the photo is done, the mirror will go back down. 

How exposure works: the digital image sensor

The aperture inside the lens is simply an adjustable opening in the lens that allows you to let more or less light through. This would be like the size of the hose. Which one of the following aperture openings would let in more light? Of course, the larger opening will.

Above is a wide aperture (low f-number), below is a small aperture (high f-number).
Guess which one will let more light through...

The shutter is the mechanism that "opens up the flow" of light to the sensor. It's like turning on the faucet. Which of the following shutter speeds (that's the duration of time the shutter is open) will let more light through: 1/100 of a second or 1/2 of a second? Well, 1/100 of a second is a much shorter time period than 1/2 of a second, so 1/2 of a second will let more light through.

How exposure works: the shutter

Here is a view of the shutter with the mirror held up out of the way. You'll notice the shutter is a set of overlapping blades that blocks the sensor from light. It keeps in the sensor in complete darkness until you actually take a photo. When you do, the shutter snaps up out of the way like a window shade so that light can soak into the sensor. When the picture is done, the shutter goes back down to block off the light. 

When you make an exposure, the shutter opens up, light flows through the aperture opening, soaks into the image sensor like water soaking into a sponge, then the shutter closes off the flow of light once enough light has been recorded.

Shutter opens > light flows through aperture > image sensor soaks up light > shutter closes. Faucet opens > water flows through hose > sponge soaks up water > faucet closes. It really is that simple. Here's a diagram demonstrating the concept:

Understanding Exposure: How exposure works on a DSLR camera

In the diagram above, you can see the aperture, shutter, and sensor all indicated along with how their setting is measured (the aperture is measured by the f-stop, the shutter is measured by the shutter speed, and the sensor is measured by the ISO). 

In the diagram below, the labels are gone to remove the clutter. This is how your camera looks when it's not taking a picture - when it's "at rest":

Understanding Exposure: How exposure works on a DSLR camera

When you take a picture, all these mechanisms have to work together to get light to the sensor so it can soak up the light and create an image. It goes like this: The mirror moves up out of the way, the aperture closes down to whatever you set it to, the shutter opens up, and the sensor soaks up the light to create an image, like this...

Understanding Exposure: How exposure works on a DSLR camera

...above is a diagram of the camera as it looks while it's taking a picture.

Some time later - maybe 1 second later, maybe 1/8000 of a second later depending on the chosen shutter speed - the camera can cease collecting light. The shutter closes to shut off the light, the aperture opens back up, and the mirror goes back down. Like this:

...now it's back to it's "resting position" ready to take another photo.

So again, shutter opens > light flows through aperture > image sensor soaks up light > shutter closes. No need to make it more complicated than that.

 

Changing One Setting Affects the Other

Much of what the exposure triangle is trying to illustrate is that if you adjust one setting (shutter, aperture, or ISO), then another setting will have to change, too, assuming you want to keep the exposure the same (i.e. collect the same amount of light). But again, you don't need an exposure triangle to understand this. It's as simple as trying to get water into a sponge. If I use a wider hose to feed water into that sponge, I won't have to leave the hose on so long. If I use a narrower hose, I'll need to leave the flow on longer. Simple.

It's no trickier than this with exposure in photography. If I open up my aperture wider, then I won't need to leave the shutter open so long (the shutter speed will be faster). If I close the aperture down to a smaller opening, I'll need to leave the shutter open longer to make up for the loss of light. More on the aperture, less on the shutter. Less on the shutter, more on the aperture. You get the idea.

But what about the ISO? Well, let's say I had some way of making my sponge (the image sensor) much better at soaking up light. In other words, I was able to increase its absorbency. Well, if I have a more absorbent sponge in my water analogy, I wouldn't need to leave the faucet on so long since it's better at soaking up water. Same goes for light. If I can make my image sensor more absorbent to light, it won't need so much time to soak it up. This is what raising the ISO does. When you increase the ISO number, you're making the image sensor more absorbent to light. As a result, the shutter will only need to "turn the flow on" for a brief time. This is why raising the ISO results in faster shutter speeds.

The Bottom Line

The exposure triangle doesn't work. It's a terrible learning tool. There is no shortcut to learning the shutter speed, aperture, and ISO. Exposure is a concept that must be understood, not memorized. Cheat sheets and the exposure triangle won't get you there. Of course you won't be an expert from this short 1,000-word explanation either. My goal here is only to show you that there is a way to understand these things through logic, analogies, and simple physics without the need for a confusing exposure triangle that relies on memorization. There is much more to it that my short summary here. This is just a foundation. That's why more than half my Introduction to DSLR Photography online course is devoted to these things alone.

Sorry to throw a sales pitch at ya, but if you want to learn these things fully, check out my Introduction to DSLR Photography online course here (perfect for beginner photographers) and in my How to Shoot in Full Manual online course here (for intermediate to advanced shooters). With a clear, concise explanation aided by example images, diagrams, and videos, you can learn exposure better than any exposure triangle can deliver.

Please download the free lesson guide and video with the full explanation of shutter speed here. Download the free lesson guide and video fully explaining the aperture here.

Links: