tailieunhanh - Photoshop CS4 for Dummies phần 3

Trong thế giới tuyệt vời của hình ảnh kỹ thuật số, bạn sẽ thấy độ phân giải được sử dụng trong bốn cách cơ bản: độ phân giải hình ảnh: độ phân giải hình ảnh là kích thước của điểm ảnh cá nhân hình ảnh của bạn khi bạn in. Tôi đi vào chi tiết hơn về khái niệm này trong phần sắp tới, "Chọn độ phân giải hình ảnh. | Chapter 4 Getting Images into and out of Photoshop 69 Purchasing commercial images Some projects require images that you can t run out and shoot yourself. Say for example that you re preparing a poster or brochure about a ski trip to Japan. In your office or studio. In the United States. In July. Pretty tough to shoot what you need eh Turn to stock photography. You can purchase or license stock images photos illustrations video and even audio from a wide variety of sources including Internet-based services and collections on CD DVD. In fact I use images from in a variety of places in this book. When you consider using stock images keep in mind the difference between royalty-free and rights-managed images. Royalty-free images are yours to use as you see fit within the terms of your agreement no resale as stock photos no defamatory or pornographic use and so on . You can use the images when you need them as often as you need them. Rights-managed images on the other hand are licensed for a specific use in specific media for a specified time. Rights-managed artwork does have one advantage over royalty-free Because usage is controlled you can license exclusive rights to the image for that period of time so that the image you use won t appear in some competitor s advertising at the same time. Royalty-free images on the other hand are available to anyone who pays for them and usage is not controlled. Determining scan resolution Before scanning an image you need to make some decisions 1 How you want to use the image 1 What its final size will be 1 What resolution you need By determining how many pixels you need beforehand you eliminate the need to resize the image in Photoshop and the resulting image degradation . Many scanner interface windows let you input the final size and resolution you need right in the scan window. If you find the need to calculate scan resolution manually here s how 1. Determine the required pixel dimensions. For print If you ll be .