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Quick review: what we’ve learned so far

There are three things that we can control that affect how a photo is exposed:

  • Shutter speed
  • Aperture
  • ISO

Shutter speed is how long the lens is open. Aperture is how wide it’s open. ISO is how sensitive the camera is to recording light.

If we leave the shutter open for a long time, a lot of light gets in. This is called a slow shutter speed. If the shutter is only open for a very brief moment, less light gets in and this is called a fast shutter speed. A fast shutter speed is useful for when we want to freeze motion and get a very crisp image, and a slower one is useful for capturing motion blur.

Fast shutter speeds are also useful for avoiding blur from the photographer’s shaky hands.

Your camera has a meter that measures light and uses that measurement to decide what exposure is best for a given situation. In fully automatic mode, the camera picks out both the shutter speed and the aperture. In aperture priority mode, you set the aperture and the camera picks the best shutter speed. In shutter priority mode, you pick the shutter speed and the camera picks the best aperture. You can also put the camera into fully manual mode so that you can choose your own aperture and shutter speed, and the camera’s meter will just offer advice.

If you’ve been following along and doing the exercises, you’ve also learned how to put your camera into different modes and what images look like at various shutter speeds.

Next up: the magic of aperture and how it can dramatically change our photos.

Next lesson: What’s that f-stop stuff anyway?

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SSA Recommends: Books, Products, Links

Books

If you go into any bookstore, you’ll find an overwhelming selection of photography books. These are the ones that I own and love, and reread on a regular basis.

Understanding Exposure is the bible of exposure. I’m teaching kindergarten here, while he’s giving a graduate seminar complete with stunning examples and clear explanations. I recommend this book to anyone who wants to get an in-depth understanding of exposure.
Learning to See Creativelyis another Bryan Peterson book, this time on composition. This book has done more to improve my skill as a photographer than anything I’ve ever read. I’ve learned to look at the world in an entirely different way, and to hunt the image that isn’t obvious. I can’t say enough good about this book.

Products

Canon 50mm f/1.8 lens Also known as the nifty fifty, this lens is inexpensive and a great bang for the buck.
Canon RC1 Wireless Remote This little gizmo is wonderful if you have a Rebel-class dSLR– it’s the best thing ever for taking pictures without touching the camera.

Equipment Rental

BorrowLenses is a fabulous place to rent camera gear. They have a great selection of equipment, and my dealings with them have been excellent. If you’re in the San Francisco bay area, they have a few different places where you can pick up and drop off your rental equipment.


Websites

Copper Hill Images sells excellent products for cleaning your camera and its components. They also have an excellent, detailed tutorial on sensor cleaning.

Strobist is an excellent resource for learning about off-camera lighting and lighting techniques.

Flickr is the site that I use for hosting and sharing images. A basic account is free, and a fully-featured one is only a few dollars a year. Image hosting at Flickr is pretty simple.

LensRentals is an excellent resource for renting lenses in order to try them out, or when you just need a special lens for a little while.  I’ve had excellent service from them.

dpreview does excellent in-depth reviews of digital cameras.  Their side-by-side comparison tool is great if you want to look at the differences between different cameras.


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Exercise: Shutter Speed

8In this exercise, we will take several pictures to illustrate how shutter speed affects the resulting image. We’re not going to take any great pictures here, but the ones we do shoot should help us get a better feel for the nuts and bolts with shutter speed.

You’ll need a friend with a flashlight, or some sort of light source that he can swing around. In my pictures I used a glow poi (basically an LED on a string) but you can just ask your friend to hold the light in his hand and move it around. You’ll also need a camera, of course, and a not-too-bright room. Oh, yes, one other thing. You’ll also need a beer or other Appealing Beverage to thank your friend for the help. If you know someone who wants to learn to use his dSLR better as well, the two of you can take turns being the photographer and the helper.

If you have a tripod, it will be useful for this exercise. Instead of holding the camera when I tell you to, put it on the tripod. If you don’t have a tripod that’s OK… blurry pictures won’t be a big problem. If you really want the shots to be perfect, find a table or something to brace the camera on when you take the photos.

Control PanelSet up your camera: To begin, set your camera to ISO 400 (if you now how… if not, don’t worry about it), shutter priority mode, and manual focus. Have your friend stand facing you. Pick a spot that will let you get his upper body in the frame plus a couple of feet on either side, and manually focus the camera on him. Focus doesn’t have to be perfect, but it should be good enough to get the light source pretty clearly. Set your shutter speed to one second. On my Canon that’s the number one with two tick marks after it.

Now, ask your friend to turn on the flashlight, point it at you, and start moving it in a circle in front of him. Ideally he should be doing this so that he makes one circle every second, but friends are unpredictable (especially if he’s already had that beer) so any speed that’s somewhere in that vicinity will work.

Holding the camera as steady as you can, take a picture. Yes, it’s a one-second exposure and you’re going to shake, but that’s OK. We really just care about how far the light moved. One second sure is a long time, isn’t it? When you’re done, check out the picture on the camera’s display, and you should see a circle of light.

Now, set the shutter speed to 1/2 second (indicated by 0”5 on my Canon), ask your friend to make a light circle again, and take another picture. Repeat this for 1/4, 1/8, 1/30, 1/125, 1/250, and 1/500 second.

500When you’re done with this, you’ll wind up with a set of photos of progressively smaller arcs of a circle of light. At 1 second, you should basically have a full circle. Half a second should get you approximately half a circle of light, and so on until you get to the very fast exposures. Look closely at the ones that are 1/125, 1/250, and 1/500 of a second. When I did this exercise, 1/500 pretty much froze the action, but 1/250 and slower had blurs of light.

When I did this exercise to create sample images, I put the camera on a tripod and used a remote shutter release rather than asking a friend to help. As I mentioned earlier, I also used a glowing ball on a string rather than flashlight. Still, the resulting images do a pretty good job of showing movement. I have them all in my photography class set on Flickr, and they’re tagged “light circle exercise”.

Note that some of your photos may have come out much brighter than others. That’s OK! What happened was that your camera wanted to make all of the pictures bright and shiny and happy at whatever shutter speed you chose. At the slower shutter speeds it probably closed the aperture down to block out some of the light. As you chose faster and faster shutter speeds, the camera opened up the lens to let more light in but at some point it ran out of room to do this because the lens was already as wide as it would go. When that happened, the camera just did its best but the photos started getting darker as the shutter speed got faster. For the purposes of this exercise that’s perfectly OK. In fact, it’s a good way to see how your camera’s photos turn out when the camera is starved for light.

When you’ve completed this exercise, you should have a bunch of pictures with streaks of light in them. The Guggenheim won’t be beating a path to your door over them, but you’ll have practiced setting your camera’s shutter speed to a pretty wide range of settings, and you’ll have a pretty good understanding of how much motion there is at a specific speed.

Oh, yes. Set your camera back to whatever ISO (probably 100) you usually use, and set the lens back to autofocus. That will save you from some confusion the next time you try to use the camera. In general, it’s a good idea to pick a set of “normal” settings for your camera and leave the camera in that configuratoin whenever you put it away. That way, if you want to pick it up and shoot something quickly you won’t have to worry about undoing whatever you did last week.

If you want to practice some more, find some other moving object and start taking pictures of it. If you have dogs or small children, you can probably persuade them to run around in the park while you take pictures. Cars, water, anything that moves somewhat predictably will be good practice for you.

If you want to share your photos from this exercise, I recommend uploading them to Flickr and tagging them with “stopshootingauto” and “lightcircleexercise” so that other people can see them just by looking for those tags.

Next lesson: Quick review, what we’ve learned so far

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Exercise: exposure modes

Are you ready for the first exercise? Great, let’s go. If you haven’t ready the last lesson on how exposure modes work, you’ll want to do that first. In this exercise, we’ll try out the various exposure modes in order to learn how the controls work.

OK, grab your camera. It doesn’t matter what lens you use, but try to find a place with a lot of light and something at least marginally interesting to point the camera at.

The first thing we’re going to do is put the camera in aperture priority mode. If this is the first time you’ve taken your camera out of its everything-automatic rut, this may be scary for you. Don’t worry, I’ll be right here to hold your hand. Now, take a deep breath and turn the dial to Av, A, or whatever your camera calls it.

See? That wasn’t so bad.

Now, pick out something nearby that you can focus on. Maybe it’s a picture or a piece of furniture or a tree, but pick something that isn’t going to move around a lot. Now, look through the viewfinder of your camera and focus on the thing that you picked out. Press the shutter button halfway, and you should see a display in your viewfinder that will tell you what the aperture and shutter speed are set to.

Turn whatever dial it takes on your camera to open the aperture as wide as it will go– remember, that’s the lowest number. It may be as low as 1.4 or 1.8, but more likely your lowest setting will be somewhere between 2.8 and 5.6. It doesn’t matter for now. Keep pointing the camera at whatever object you picked out.

If you did that quickly enough, which you probably didn’t, you’ll still have a display in your viewfinder. If not, push the shutter button down halfway to get it back. Make a mental note of what shutter speed the camera has picked out. Now, turn the aperture dial a few clicks. Do you see the shutter speed change? (If the display goes away, just keep pressing the shutter button halfway.) Keep doing this until the aperture is as small as it will go– most likely, that will be around 22, but your lens may be different.

Did you notice how the shutter speed changed automatically every time you changed the aperture? That was your camera’s meter picking out the right shutter speed to go with the aperture you chose. It’s possible that your camera had trouble with the highest and lowest settings, and couldn’t find a shutter speed fast enough or slow enough to work. If so, it probably kept the needle all the way on the left or right of the meter display, and maybe flashed it or beeped or complained in some other way. If so, remember that for the future. It’s your camera’s way of saying that something’s not right.

Now, let’s do the same thing but in shutter priority mode. Set your camera to Tv or S or whatever. Look through the viewfinder, and press the shutter button halfway. Turn the magic dial to change the shutter speed, and watch the selected aperture change. If you pick a really fast shutter speed like 1/1000, there’s a good chance you’ll get to see how your camera complains about bad exposures.

OK, there’s one more step, but before we take it you probably need a quick break from all this scariness. Get up, walk around the room, do a jumping jack, grab a beer, or do whatever it takes to get past all the scariness I’ve thrown at you.

Are you back? Excellent. Now, we’re going to do one more scary thing. Set the camera to manual mode. Ready? Deep breath. OK, go.

Still with me? Great! Now, set your aperture to f/8, using whatever control your camera uses to change the aperture in manual mode. Now look through the viewfinder and press the shutter halfway. See the indicator on the meter? It’s probably way off to one side. Keep looking through the viewfinder while you turn whatever dial changes the shutter speed. Keep doing this until the indicator is right smack dab in the center of the scale. When you get it there, take the picture.

Guess what? You just took a photo in manual mode. If you view it on the camera’s LCD, you’ll probably see that it looks pretty good. Pretty cool, huh?

If your room isn’t very bright, there’s a chance that you couldn’t make that work. If so, set the aperture as wide as it will go and try again, or go somewhere with more light.

Next lesson: Shutter speed exercise

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How your camera works– exposure modes

ModeDialOK, this is what you’ve been waiting for… we’re about to take our camera out of automatic mode. How do we do that? It’s really very easy.

Somewhere on your camera there’s a dial that looks a little bit like this one on my 5D. It will have several settings to choose from, and may have many more than what’s shown in this photo. In order to set the exposure mode, you turn the dial so that the appropriate setting is lined up with the indicator line on the side. The line is a little bit hard to see in this photo, but the camera is in M mode. M is for manual, Magic, Master of the universe, and My favorite mode.

What are all those other modes?

  • Green box: the camera just does everything for me
  • P: program mode, which is much like the green box but a little less neurotic
  • Tv: shutter priority mode
  • Av: aperture priority mode
  • M: manual mode
  • B: bulb mode
  • C: custom function mode (which I’m going to ignore)

I shoot with Canon gear, and therefore I’m most familiar with Canon’s controls. Those are also the cameras that I have sitting around to use as examples. (If anybody wants to send me a Nikon so that they can have equal representation, I’d be happy to go the extra mile.) I believe that Nikon calls their controls Auto, P, S, A, and M for Automatic, Program, Shutter Priority, Aperture Priority, and Manual. Other brands will have very similar functions– if you can’t figure out what they are, consult your manual.

In Auto and P modes, the camera basically just does everything for you. Typically, Auto mode is extremely obsessive about it, and won’t let you change any of the settings on your own. P mode is kind of a laid back version of Auto, one that will set the shutter speed and aperture for you, but not ignore you if you try to change something else.

Aperture priority and shutter priority are the real workhorses, and many people find that they use aperture priority more than anything else. You might too, once you figure out how they work. In aperture priority mode, you pick your own aperture, and then the camera’s meter figures out what shutter speed to use. As you can probably guess, in shutter priority it’s just the opposite– you pick the shutter speed that you want, and then the camera picks an aperture. Pretty easy, huh?

Manual mode is the final mode that you might want to use on a regular basis. In manual mode, the camera keeps its grubby little paws off the settings, and you get to choose both the shutter speed and the aperture. That sounds like a scary amount of power, right? Well, it’s not so bad. The camera’s not going to do any work, but it will still give you information. Even in manual mode, the camera’s meter works just fine, and you can use the display to help you find the right exposure.

Just for completeness, bulb mode is a special manual mode. In bulb mode, you press the shutter button once to open the shutter, and press it again to stop. This seems like a weird thing to do, and you’re right, but it’s occasionally useful for things like taking pictures of stars. You’ll probably never need to use bulb mode, but tuck the information into a corner of your brain in case it ever comes in handy.l

You’re probably wondering how you set the aperture and shutter speed on your camera. Frankly, I have no idea but if you bring it over here I’ll figure it out and tell you. Or, you can grab the manual and look it up. Here’s how mine work:

Canon 5D: There’s a dial right behind the shutter button– it controls the shutter speed. There’s a thumb wheel on the back of the camera that controls the aperture.

Canon Digital Rebel XT: There’s a dial right behind the shutter button. In aperture priority mode, this button controls the aperture. In shutter priority button, it controls the shutter speed. In manual mode, that dial controls the shutter speed. In order to set the aperture in manual mode, you press the top button (labeled Av +/-) on the back of the camera and hold it down while turning the dial. Yes, that’s a little confusing to describe. It’s actually pretty easy to do, and once you get the hang of it you’ll find it quite easy.

Next up, our first exercise!

Next lesson: Exposure modes exercise

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