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Monday, December 21, 2015

Canon Digital Learning Center Offers Tips On Getting Sharper Images

Laura Morita of Canon Digital Learning Center offers 10 tips on how to get sharper family images during the holiday season when friends and family congregate and lots of photos are taken to remember the gathering. Must admit I rarely do any of the following myself.

1. Choose a focus point — put focus where YOU want

Focus points are the small boxes you see in your camera’s viewfinder. It’s here that your camera’s AF (autofocus) system is able to “read” your subject, and drive the lens to deliver a sharp image. If you're just getting out of automatic green mode, then it's likely that you've also been relying on your camera's automatic AF (autofocus) point selection. With automatic AF point selection, all your camera’s AF points are active — you are letting the camera grab focus on whatever it deems important. This may or may not be what you consider important. You also have the option of switching to Manual AF point selection mode. In this mode, you choose one AF point, and you determine what you want to focus on by placing that AF point on that area of your scene  or subject.

For portrait photographers, this is most often the subject's eye that is nearest to the camera.
When I am shooting a portrait, I determine what I want my composition to be and then toggle my AF point so that, when looking through my camera, I am able to place my active focus point on my subject's eye. This helps ensure that my camera will focus on what I deem important.

Some photographers have success in focusing via a method called "center focus—recompose." When focusing in this way, the active focus point is always the center point. You simply place your center point on the subject's eye, press the shutter halfway down to get focus, and then keeping the shutter pressed half-way, you recompose your shot to get the composition you want, and fire off your shutter.

While there are professional photographers who use this method, I have never had success with it. Even though it seems like a simpler way to focus since you don't have to manually move your AF point, I find that I often end up with an out of focus image because while I recompose, I inevitably slightly change the distance between my subject and camera. That said, try it out for yourself and see if it works for you.

2. Choose a faster shutter speed

A fast shutter speed freezes motion. This is critical in getting a sharp image. If your subject is moving faster than your camera can capture, there will be motion blur which leads to a less than sharp image. Likewise, if you are handholding your camera and move the camera when you press the shutter, that movement will decrease the sharpness of the entire image. A general rule of thumb for handholding your camera is it should be 1/the length of your lens. That is, if you have a 200mm lens, your shutter speed should be at least 1/200th of a second. If you are shooting with a 50mm lens, then you should shoot with at least 1/50th. But that is only part of the equation. You also have to take into account the movement of your subject and how much you move when you press the shutter. In general, I try to keep my shutter speed at or above 1/500th when shooting moving children. If you're photographing moving animals, that might need to be even faster. I also know that I am not the most "zen" shooter, moving around rather wildly when I shoot. For example, I love shooting with my Canon 135mm f/2.0L lens, and while the "rules" would say I should be able to get a sharp photo when shooting at 1/200th, I find that I don't get consistently sharp images unless I'm shooting at at least 1/500th. Others might be able to nail focus at 1/200th but I have some sort of genetic predisposition to be a non-zen, wild shooter, so that just doesn't work for me. What can I say? I'm such a rule breaker.

3. Pay attention to your aperture

Aperture is responsible for your depth of field—how much of your image is sharp and how much of your foreground and background are blurry. When you have a large aperture, designated by a low f/stop number, you'll have a narrower area that will be in focus — backgrounds will tend to be thrown out of focus. When you have a small aperture (a high f/stop number), more of your image will be in focus. Many portrait photographers like to shoot with a large aperture, like f/1.4, f/2, or f/2.8, because this allows their subject to be separated from the background. A background of trees that are blurry and out of focus doesn’t draw the eye as much as the same trees that are much more in focus. So, while the goal for most portrait photographers is a wide aperture, this takes practice. The larger the aperture, the less that will be in focus. This is where getting your AF point right over an eye is critical in getting that tack sharp photo you want. And keep in mind that even the slightest turn of your subject's head could mean that one eye is sharp and the other isn't. That might not bother you in the slightest, which is the great thing about photography. You get to decide what you want in focus and what you don't.

My advice here? Practice. If your images are all out of focus when you shoot at f/2.8, try stopping down your aperture a little. Maybe try f/4.0 and see what happens. When you are nailing focus at f/4.0, then try a slightly larger aperture and practice some more!

4. Keep your ISO as low as you can

The higher your ISO, the more sensitive the camera is to light. The downside of this added light sensitivity is the introduction of digital noise, or grain. This will be seen in your photos as little dots in the image, more noticeable in the darker parts of your image. This noise will decrease the clarity of your image and make your image look less sharp. In post-production, there is a variety of noise reduction software that can help reduce noise, otherwise known as grain. While it will help clean up noise in the image, use it sparingly because the noise reduction will slightly blur your image so be careful. But nothing beats just having less noise to begin with. And working at lower ISOs, such as 100, 200, or 400 — when you have enough light to do so — will deliver exactly that.

5. Ensure that your subject is well lit

As we begin to delve into photography, we can get wrapped up in so many things: aperture, shutter speed, ISO, composition, the subject's expression. But let's get one thing very clear: photography means quite literally "the drawing of light." Without light, there is no photography. While part of getting good light has to do with your ISO, discussed above, there is more to it than just your ISO.
If your subject is well lit, they will have light in their eyes, known as catchlights. Those catchlights will give vibrancy and clarity to your image. If you nail focus with a well lit subject, man oh man, you'll know it. Good light will make your image crisper.

When there isn't good light, your camera will struggle to lock focus on the eye since there isn't enough light to give contrast to the eye. Your camera needs good light so that there is a clear edge for it to focus on. You may hear the lens whirring back and forth as it tries to lock focus to no avail. Move your subject to a well lit place, and you won't have this difficulty.

6. Learn how to hold your camera

I remember seeing a picture of me holding my camera when I hadn't yet learned the importance of it. I had my elbows out like I was ready to take flight and claw hands on both sides of my camera. Once I learned how to hold my camera correctly, I noticed a nice improvement in the quality of my images. When you're taking a picture, the steadier you hold the camera when you press the shutter, the more likely you are to avoid camera shake and get a sharp image. Here are some tips to decrease camera shake :

  • Stand with your legs apart. When you have a wide base of support, you will be more stable.
  • Tuck your elbows into your body as much as you can.
  • Hold your left palm upwards and place your lens in the palm. By cupping the lens with your elbow tucked in, you greatly improve your stability.
  • Breathe out while you gently press the shutter button with your right index finger. If you're in the middle of breathing or holding your breath, you're more likely to move your camera.
  • I just alluded to it above, but just to reiterate: GENTLY press the shutter. If your stabbing at your shutter button, you are more likely to shake your camera and have a less-than-sharp image.
  • If you are shooting in portrait orientation, rotate your camera so the shutter is on top.
  • Hold the viewfinder to your eye and gently hold it against your face. This helps to keep the camera from moving.

7. Turn on image stabilization

If your lens has image stabilization, turn it on. It's a switch on your lens and will help minimize any sort of movement or camera shake you introduce to the camera as you're shooting. 'Nuff said.

8. Choose the right AF Operation Setting

Your Canon has three different AF Operation Settings, sometimes called Focus Modes. Basically, these set up the AF system for stationary or moving subjects.

ONE SHOT AF : One shot is best for stationary subjects. When you shoot with ONE SHOT, you'll hear an audible beep and see a green light inside your viewfinder letting you know that focus has been achieved.  If you keep the shutter button half-way down, focus stays locked, and you can re-compose the scene if you want.

AI Servo AF : AI Servo AF is best for moving subjects. With AI Servo, you hold your shutter button half-way down and your lens will continue to focus on your subject, even if s/he is moving. (Just so you know, “AI” is an abbreviation for Artificial Intelligence.)

AI Focus AF : AI Focus is a hybrid between ONE SHOT and AI Servo. It automatically detects when the subject is stationary, and will choose ONE SHOT AF; if there is movement, it automatically will detect this, and will switch to AI Servo AF. I personally don't use this and prefer to choose whether ONE SHOT or AI Servo suits my needs.

In some Canon models, you have the option of setting your depth-of-field button, located below your lens mount, to toggle between the ONE SHOT AF and AI Servo AF. I love this feature. I keep my focus mode set to AI Servo, but if I want to use ONE SHOT (which I love because that little "beep" gives me assurance that focus has been achieved), I press the DOF button. Best of both worlds without needing to go into my menu. I love that.

9. Setting your drive mode to continuous shooting when grabbing focus is of utmost importance.

I pretty much always have my drive mode set to continuous shooting. This means that if I hold my shutter down, my camera will keep on firing off shots. Firing continuously isn't something you want to do every single time you take pictures. Sorting through a bunch of almost identical photos is a pain, plus it will eat up the space on your memory card pretty quickly. But when getting THE shot is important, shooting in continuous mode can be just what the doctor ordered. It will increase the chances of not only getting sharp focus, but also getting the best moment, the best expression, the best giggle.

10. Consider setting your camera to back button focus

I couldn't live without back button focus. Well, that's not true. I couldn't live without oxygen. But, back button focus is up there. You know, after food, and water, and, well... you get the idea. Back button focus was another game changer for me in my quest for tack sharp focus that made a wonderful difference in the sharpness of my photos.

The basic gist behind back button focus is instead of pressing your shutter halfway down to grab focus and then pressing it down all the way to take the shot, you designate a different button, either the * button or the AF-ON button (in some cameras) to be in charge of focus. These buttons are located in the back of the camera, thus the term "back button focus." The shutter now only serves the function of taking a picture. It no longer has anything to do with focus.

When this method was first brought to my attention, I didn't understand why I would want to ever make focusing any more complicated. Another button to have to deal with? I had enough buttons and dials to keep me plenty busy. But everyone kept saying to just give it a try. And so I finally did. It took some getting used to, but once I had it figured out, I could see an improvement in my focus.
Here's a great example of when back button focus made all the difference in my getting a sharp photo.

My kids love swings. Don't all kids? They are totally the kids at the park that stalk the swings until a kid jumps off and then they completely monopolize the swing set and unless gently reminded that maybe another kid might want to get on, they just stay on and swing until it's time to go home. But I digress.

Because they love swings, I have had many opportunities to photograph them. I like to photograph them at the peak of their swing, as there is a moment of "air time" when they switch directions where I'm more likely to grab focus. Back button focus is my friend here. If I were using the shutter button to grab focus, there is a brief moment where focus has been achieved but the shutter hasn't been fully pressed. In that moment, they can move out of my focal range, thus meaning I miss focus. Missed focus is even more dramatic if you're shooting with a wide aperture (low f/stop number, like f/2.8 or f/2), as your depth of field is quite shallow. But if I'm using back button focus in combination with AI Servo AF (discussed in #8 above), I can hold my thumb on that back button the entire time he's swinging, even when I fire the shutter. This means I'm getting the most up-to-date focus I can get!

This image was shot at 1/800th of a second to freeze motion, and because I wanted to ensure that his face would be in focus, and I wasn't concerned with whether or not the background was in focus, it was shot at f/7.1. This allowed for a deeper depth of focus (a great area in focus), which increased my chances of the face being in-focus in the final shot.

Back button focus comes in handy not only with swings, but any time you have a fast moving subject where there's a chance they'll move out of your plane of sharp focus.

Do your kids play sports? Another great reason to use back button focus. You can be focusing on the star of the game (obviously your kid), and if another child runs in front of him or her, you can just take your thumb off of the back button and keep on shooting. As long as your child doesn't move out of your plane of focus, you can keep shooting, and once the other kid moves, you can use your thumb again to track your child’s amazing athletic moves.

I also find back button focus invaluable in getting the composition I want in camera. While I do my best to put my AF point on an eye by moving it to the nearest location in the frame, sometimes I still need to recompose my shot to get the composition I want. If I were taking a series of images with my shutter button being responsible for my focus, this would require me to 1) put the focus point on the eye, 2) press the shutter halfway down, 3) recompose, 4) shoot, and then repeat steps 1-4 for every image taken with that composition. Phooey! By switching to back button focus, I only have to grab focus once, and as long as the distance doesn't change between my subject and me (no one moves), I can fire off a series of images, confident that I'm nailing focus.

Here's an example. I knew I wanted to compose the image as seen here. I wanted my son off to the side, leaning on a tree trunk, with the cherry trees in the background.

For the sake of keeping things simple, let's say I have a 9 point AF system. If I were to have my composition exactly as seen above, I would find that there is no AF point that goes exactly over his eye. I, therefore, would manually move my AF point to the one that is closest to his eye, compose my image so that the AF point is directly over his eye, press the back button to get focus, then LET GO of the back button. At this point, this is what I'm doing:

From here, I would recompose and fire off a shot. Because my shutter button is no longer responsible for focus, the fact that my AF point is pointing at something way out there in the background is irrelevant. As long as I keep my thumb off of the back button, my focus will not change and will remain locked on his eye.

Now knowing that I have achieved focus, I can wait for him to do something adorable (happens all the time), and fire off shots without ever needing to get focus again. If I used my shutter button to get focus, I would inevitably miss the moment.

Ready to give back button a go? Check out this article for more information about the wonders of back button focusing and how to do it with your camera.

So there you have it! Follow these 10 tips and you will be rocking the sharp images in no time!

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