Where shutterbugs unite to share their wisdom, skills and resources
This post is the first of a two part series for beginners looking to improve their photography skills. We will be looking at the very basics of how a camera works, and how it influences the final result.
by Janco Wolmarans
Most people buy a digital camera, turn the mode dial to “Auto” and let it rust there. If you want to improve your photography skills, this is the first mindset you need to ditch. We’ll be looking at three modes supported by most cameras, and which will get you started on the way to better pictures.
So why would you not want to use auto mode? In auto, the camera tries to guess the best settings for whatever you happen to be pointing it at. Unfortunately, this is all done by software on the camera, and as a programmer myself, I can assure you that machines rarely know what’s best. Simply put, auto puts the camera in control, and if you’re serious about becoming a better photographer, YOU need to be in control.
Before jumping into a discussion of the different modes, we need to establish some photography fundamentals. Arguably, the two most important camera settings that influence the final result, are what’s called shutter speed and aperture.
Shutter speed controls the amount of time for which the shutter (a divider or curtain of some sort), is open while taking a picture. The shutter sits between the camera lens and the sensor (in the old days this used to be film). The longer the shutter stays open, the more light is captured onto the picture and vice versa. Slow shutter speeds can cause blurry pictures if the camera is not kept still, or if the subject moves while taking the picture. Faster shutter speeds will tend to freeze subject motion, but might be underexposed (dark) if not enough light is available.
The following clip demonstrates how the shutter works, and the effect of setting the shutter speed. The camera used here is an old film type SLR, but the principle holds true for digital cameras. 500 points to you if you can honestly spot the open shutter when set to 1/1000 of a second .
Aperture controls the amount of light that passes from the lens onto the sensor, and is measured in what’s commonly called “F-Stops”. The lower the “F number”, the wider the aperture, and the more light it lets through. In low light situations, you would typically open up the aperture to let in as much light as possible. Shooting with a wide aperture has an interesting side-effect (referred to as shallow depth of field), which causes the subject to be in focus, and anything else behind (or in front), to be out of focus. With a narrow aperture, more of the framed picture will be in focus. For the science behind the effect, see this article on Wikipedia
This clip shows what physically happens inside the lens when you change the aperture.
Both of these settings affect how much light is captured onto the picture, but the side-effects of changing each individual setting are different. Though not critical, I would encourage you to do some further reading on these two aspects of photography, as I have only lightly touched on it. Top professional photographers typically opt to shoot in manual mode, where they control both the shutter speed and aperture. In part two of this series, we will be exploring some intermediate operation modes which fall somewhere between auto and manual. These are great for weaning yourself off the auto addiction.
by Janco Wolmarans
In part one of this series we discussed why it’s important for you to be in control of your pictures, instead of your camera. We also touched on the subjects of shutter speed and aperture. Today we’ll be looking at two camera modes that center around these settings.
Aperture and shutter speed are the Yin and Yang of photography, and they typically form a delicate balance. As mentioned in part 1, both affect the amount of light that reaches the sensor, but the side effects of adjusting these two aspects are different.
Setting your camera to aperture priority (Av on Canon cameras), lets you determine the aperture, and the camera will adjust the shutter speed accordingly, in an attempt to maintain decent exposure. In shutter priority mode (Tv on Canon cameras), you set the shutter speed, and the camera will adjust the aperture accordingly.
Why fiddle with these settings?
We’re all familiar with those photos where the subject is in focus, with a nice soft, blurry background. If you’ve only ever used the camera in auto mode, some of your pictures may have come out like that, some not, and you have no clue as to why and when it happens. If you’re specifically looking to achieve this effect, you need to have the aperture as wide open as possible. The following two images demonstrate the effect of changing the aperture. Image A was taken with a relatively wide-ish aperture of f/4.0, and resulted in the foreground as well as the background being out of focus. For image B, the aperture was set to a narrower f/25.0 – And although not everything in front or behind the subject is perfectly focused, the effect is obvious. Note also that because I had the camera set to aperture priority, it automatically adjusted the shutter speed for me (1/500s for image A, and 1/13s for image B), to maintain a consistent exposure on the two images.
So much for aperture, what about shutter speed?
If you want to freeze any motion in your photo, you need to shoot with a high shutter speed. Slower shutter speeds will start blurring if the subject performs any kind of motion (or if you can’t keep the camera still enough). Opting for a higher shutter speed will in most situations require the aperture to be widened. The shutter remains open for a shorter period, which causes less light to be captured by the sensor. Opening up the aperture will allow more light through. Conversely, if you close the aperture to have more of the framed image in focus, you may need to slow down the shutter speed in order to let more light through and prevent your pictures from being underexposed. Compare the following two images: Image A was taken with a fast shutter speed of 1/400s and the drops of water are nicely frozen in mid-air. For image B, the shutter speed was set to 1/15s causing the water to produce a streaking effect.
Back to (almost) auto
There’s also a setting called Program Auto mode, which works a lot like auto, but the camera allows you to change a couple of settings. Program auto will (like full auto) select what it thinks is the best shutter speed and aperture combination. Where it differs from full auto, is that it will allow you to manually select from different combinations while maintaining a decent exposure. You can also set things like ISO and white balance (we’ll discuss these in future posts). In full auto, the camera decides when to fire the flash, while Program auto will not flash automatically, and you determine whether or not to use the flash. Program Auto is a great “walk-around” mode to have your camera set to. You have the ease of auto, but can still maintain a level of control. For everyday shots, I personally keep my camera set to programmed auto, and prefer to use the AE-lock function to override exposure settings where necessary.
If you’re a beginner (or an experienced auto-only-shooter), I hope this article has at least inspired you to start experimenting with the mode dial on your camera. Remember, you can’t advance your photography technique if you don’t experiment.