Digital cameras you several options to control their exposure. Know how to use them to get the best results for your photography? In the first SLR cameras (film) were totally manual. A photographer needed to understand the configuration of opening and shutter and how to use them. Then came the automatic mode, allowing the camera does the thinking for you. This was (and remains) a fairly reliable way to get a well exposed image, but he had the creativity of the photographer's hands. Over time, few people learned manual dexterity. As camera technology improved, the quality of most of the photos even worse. Today we have the best of both worlds. All DSLR cameras and compact digital cameras have automatic and manual modes, but also offer semi-automatic mode. This means that you can get a little 'creative, and allow the camera to control exposure for you. If you have the priority and aperture priority shutter of the camera, but never understood what they were, this article is for you. First, that it is openness and speed? These are the two mechanisms to control the level of exposure in the photos, if your photo will be overexposed, underexposed, or just right. To explain properly would require much more in-depth article, that's just a quick downward. The opening is the size of the hole that allows light into the picture. Think about how the iris in the eye – as the light is low, you open the aperture to allow more light inch aperture also controls the depth of field, which affects the amount of your image is in focus. When you have a small opening, has a great depth of field, so that the subject and the environment can be in focus. When the opening is wide, the depth of field is much smaller, making it much less space around the subject, which will be focused. Shutter speed is the time allowed to each show. The shutter opens to allow light, so that the most open, the brightest of the show will be. The shutter speed also controls how motion capture in a photo. If you want to freeze a moving subject, you must use a fast shutter speed. The trick is to combine the opening and adjusting the shutter speed to get better results. If you get the right balance, your photo is perfectly exposed, and you have creative control over the look of the image. Of course, this is easier said than done. To help manage the challenge, now has the option of opening and shutter priority. These semi-automatic mode let you take control of a stage, and the camera automatically adjusts the other. This allows you to have some creative input, with the safety net of knowing that the camera allows you to manage the level of exposure. You decide how you want your picture to look, and the camera make sure it is properly exposed. So, what you choose: Shutter Priority or Aperture Priority? Well, it's all a question of priorities …. Remember that the opening of controls depth of field. So, if the range of fire is the critical element in the photo, choose the priority of opening. You can set a small aperture to maximize depth of field, or a large opening to focus attention on the issue. In any case, the camera adjusts the shutter speed to give the best exposure. The shutter speed controls the movement in a photo. If control of a moving object is the cornerstone of your image, select the priority of speed. This allows you to set a fast shutter speed to freeze subject movement, or a slow shutter speed to capture motion blur. Whatever you choose shutter speed, the aperture of the camera to ensure that the picture is exposed correctly. So the choice of aperture priority or shutter-priority depends on the type of subject to photograph and how you want to display in the photo finish. It 'really a perfect marriage between art and technology, which allows you to concentrate on their creative choice and not technical problems. There is much to learn about this topic, a short article like this is just a starting point. However, if you read your camera manual and scratch his head (as many do), this brief introduction, in simple terms to help you make sense of openness and shutter priority.