Captions are optional in most circumstances, and should not be used in lieu of alt text and image descriptions. To be fully accessible, providing both alt text and image descriptions is recommended. The below descriptions explain the difference between alt text, image descriptions, and captions. Return to Table of Contents The Difference Between Alt Text, Image Descriptions, and Captions When describing visual material, be attentive about describing content as well as aesthetics and style. Image descriptions are necessary for most visuals except for those solely included for aesthetic and decorative appeal.

These guidelines provide examples for creating image descriptions, but please be aware that aspects of these guidelines may also be applied to visual descriptions more broadly. The term вЂњvisual descriptionвЂќ can explain when someone describes the visual context of a location, person, or space in real time, and it may also be used in reference to image and audio descriptions. Visual descriptions provide information about the visual appearance of spaces, objects, people, and more. Importantly, image descriptions are a type of visual description. Printing the text of an image description may also provide sighted readers another option for processing visual information. Image descriptions may also be used in printed products, especially when printed in Braille, to provide information about the visuals supplementing text. This ensures that information presented in a purely visual format, especially a digital graphic, is accessible to anyone who may not be able to physically see the visual for any reason.

These descriptions support the inclusion of blind, low vision, and low-tech users of all AAA products. Image descriptions provide a textual description of images presented in digital documents. Poster/Gallery Session Guidelines for Success & Accessibility.Presentation Guidelines for Success & Accessibility.Simplifying the alt text and image description process.The Difference Between Alt Text, Image Descriptions, and Captions.This page was last updated in п»їAugust 2019п»ї. If you would like to print these guidelines or view them as a PDF, you may review them in both standard print and large print format. The below table of contents is interactiveВ to help you navigate this page so that you are able to review the information more easily. With ultra high speed video cameras frequencies up to 2в™±0 7 are possible.Guidelines for Creating Image Descriptions With a drum camera recording frequencies up to 10 5 are possible and with rotating mirror cameras even 10 7 frames per second. FigureВ 1 shows photographs made by such a camera. During exposure the image has to be driven like the film in order to compensate for the effect of film transport and avoid distortion this problem is solved by optical components like the rotating prism. Cameras with continuous film transport make it possible to record up to 10 4 frames per second. The specific camera construction depends on the recording frequency. All cinematographic cameras - except image converting cameras-use moving parts for separating the images. For investigation of boiling phenomena for example, high speed cinematography is a helpful tool. With ОЅ A as recording frequency and as projection frequency in frames per second then ОЅ AОЅ P). Time-lapse photography allows analysis is of slow changes of an object for example the melting process by subsequent observation or measurement.

Photo analysis example