After this I reduce the shutter speed still further, until the meter reads overexposed by over 2 stops. Then I increase the shutter speed until the meter reaches 0 correctly exposed again. If you have a camera with an electronic viewfinder , or you use your camera's rear LCD for composing your photos, then you don't need to worry so much about reading the camera's meter.
You can see any changes made to exposure on the screen, so it's easy to see if the current settings would result in an underexposed or overexposed photo without looking at what the meter says. While cameras have quite advanced metering systems, they don't always guess the 'best' exposure correctly. A common problem is underexposed images when shooting bright subjects like snow and sand.
Taking control of the exposure allows you to set exactly the exposure you want. Maybe you want to create a silhouette image, or a low key image. Just dial in exposure settings that will create a dark image.
Ignore the camera's meter telling you that the image will be underexposed, as this is what you want! Twilight Friends! The same thing goes for creating a very bright or high key image. With manual exposure mode you can adjust your settings to create this look easily without having to worry about the camera's metering system. In a semi-manual mode, such as Aperture Priority or Shutter Priority, you can use exposure compensation to adjust the brightness or darkness of an image.
But this is not as flexible as full manual mode. In manual mode you can adjust by as many stops as you like. In low light conditions , camera metering systems seem to get increasingly unreliable, often resulting in an underexposed image. Instead, it is usually better to rely on manual exposure.
The majority of cameras only allow down to 30s as the longest possible shutter speed. After that you are required to use 'bulb mode', where the shutter is held open until you release it. Usually holding down the shutter button for the period of the exposure, or sometimes pressing the shutter once to start and then again to finish. So for long exposures over 30s you have no choice but to use manual exposure.
Panoramic images can be created by taking multiple overlapping photos and then stitching them together. Many cameras today have a panorama option that can produce good results automatically. But this doesn't work well in every situation, and in some cases you may be better off taking individual photos and then stitching them together on the computer. In this case, it is important that the same exposure settings are used for each photo.
If you use an automatic exposure mode, it's unlikely that the camera will select the same exposure for each photo. This will result in a panorama where there are visible transitions between the images used as they are of different brightness.
In an automatic exposure mode, you can use exposure lock to keep the exposure the same for the images. But it is often more convenient to just use manual exposure mode. The exact way exposure lock works depends on your camera settings.
But it will involve either holding down the exposure lock button while taking the photos, or taking all the photos quickly one after the other, or having to remember to press the button again once you're done and hoping that you don't accidentally press the button at any other time. Manual exposure is easier. If you are shooting a subject moving where the background is changing in brightness, then manual exposure can be handy.
This will let you lock the exposure based on the correct exposure for the subject. An example could be a bird leaving its nest, flying past some dark trees, then flying across the bright sky. The dark and bright backgrounds would likely fool the camera into overexposing and then underexposing the subject. With manual mode, once you've got the correct exposure for the subject dialed in, you don't need to worry.
It doesn't happen very often, but there may be some occasions where you want to control both the shutter speed and aperture. For example, you might want to use a relatively small aperture e. Unless the pitch was very brightly lit, the semi-manual exposure modes would not work very well. Shutter priority would let you choose a fast shutter speed, but would choose a wide aperture e. Aperture priority would let you choose a small aperture, but would choose a slow shutter speed to achieve a good exposure.
In manual mode you can choose both the aperture and shutter speed as you like, then rely on boosting the ISO or the use of flash to give you a good exposure. Most cameras today feature auto ISO as well, so you can still rely on the camera setting the correct exposure by automatically adjusting the ISO setting if you like. Most modern speedlight flashes feature what is known as TTL flash.
Opening the shutter exposes the camera sensor to light, which allows it to create an image. The duration the shutter is open for controls how much light will affect the sensor. If the shutter is open for too long, the photo will be overexposed.
If the shutter is open for a duration that is too short, the photo will be underexposed. This is known as camera shake. If you have a moving subject and use a slow shutter speed , your subject will be blurred.
This is known as motion blur. In the manual exposure cheat sheet, you can see the graphic of a person running. At a shutter speed of 1 second, the figure is very blurred. The relationship between how fast your subject is moving and the shutter speed will determine how much blurring occurs. You can adjust the shutter speed to help balance your exposure and to control blur from camera shake or motion. Motion blur and camera shake, or a lack thereof, can be used creatively in your photography.
A low number means your sensor is going to be less responsive than when you use a high number. I prefer to use my ISO as a foundation for my exposure. I generally only adjust it when lighting conditions change significantly. Outside on a sunny day, you will want to choose a low ISO. Inside or at night, you will want to choose a high ISO.
Unlike your other two exposure settings, ISO has no creative influence on your photos. It will affect the technical quality, though. At higher ISO settings, digital noise will start to appear in your photos. The color and contrast will also tend to flatten out. In the manual exposure cheat sheet, you can see that lower ISO settings mean the sensor is less responsive compared to higher ISO settings. To avoid seeing digital noise in your photos, always aim to use the lowest ISO setting you can.
Plus one stop means the exposure is doubled. Minus one stop means the exposure is halved. A stop can be controlled by aperture, shutter speed, or ISO. If you adjust one setting by plus one stop, you can always achieve the same initial exposure by adjusting another setting by minus one stop, and so on. As you can see on the cheat sheet, the increments I have used for the shutter speed and ISO are clearly half or double the adjacent numbers.
The f-stop numbers appear a bit random, however. This is because they indicate the aperture opening size in relation to the lens focal length. But each f-stop setting is either half or double the setting on either side of it. Manual exposure of your photographs is not so complicated. All you need to do is manage the relationship between the three exposure settings. The relationship between aperture settings, exposure, and depth of field is plain to see on this cheat sheet.
How your choice of shutter speed affects both exposure and blurring is also well illustrated. Keep your ISO in mind and make it as low as you can. Print the manual exposure cheat sheet to make learning and mastering Manual mode a little easier. It will not happen without some commitment and practice.
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