Photograpy Edinburgh

Digital Photography Edinburgh

Edinburgh Digital Phtographer John McKenzie offers detailed information on how today's modern day digital cameras and digital editiing suites have changed the way we use and distribute photographs.

Digital photography is a form of photography that uses digital technology to make images of subjects. Until the advent of such technology, photography used photographic film to create images which could be made visible by photographic processing. By contrast, digital photographs can be displayed, printed, stored, manipulated, transmitted, and archived using digital and computer techniques, without chemical processing.

Digital photography is one of several forms of digital imaging. Digital images are also created by non-photographic equipment such as computer tomography scanners and radio telescopes. Digital images can also be made by scanning conventional photographic images.

 

Digital Storage vs Film

Nearly all digital cameras now use built in and/or removable solid state flash memory. Digital camcorders that double as a digital still camera use flash memory, discs and internal hard disks. For a time floppy disks and mini-CDs were used in early digital cameras such as the Sony Mavica range.

Most digital cameras utilize some form of removable storage to store image data. While the vast majority of the media types are some form of memory card using flash memory (CompactFlash, SD, etc.) there are storage methods that use other technologies such as Microdrives (very small hard disk drives), CD single (185 MB), and 3.5" floppy disks.

 

Digital Photograph Formats

The Joint Photography Experts Group standard (JPEG) is the most common file format for storing image data. Other file types include Tagged Image File Format (TIFF) and Raw data formats.

Many cameras, especially professional or DSLR cameras, support a Raw format. A raw image is the unprocessed set of pixel data directly from the camera's sensor. They are often saved in formats proprietary to each manufacturer, such as NEF for Nikon, CRW or CR2 for Canon, and MRW for Minolta. Adobe Systems has released the DNG format, a royalty free raw image format which has been adopted by a few camera manufacturers.

Raw files initially had to be processed in specialized image editing programs, but over time many mainstream editing programs, such as Adobe Photoshop (which has become recognised around the world as one of the most used photo editing tools) have added support for raw images. Editing raw format images allows more flexibility in settings such as white balance, exposure compensation, color temperature, and so on. In essence raw format allows the photographer to make major adjustments without losing image quality that would otherwise require retaking the picture.

Formats for movies are AVI, DV, MPEG, MOV (often containing motion JPEG), WMV, and ASF (basically the same as WMV). Recent formats include MP4, which is based on the QuickTime format and uses newer compression algorithms to allow longer recording times in the same space.

Other formats that are used in cameras but not for pictures are the Design Rule for Camera Format (DCF), an ISO specification for the camera's internal file structure and naming, and Digital Print Order Format (DPOF), which dictates what order images are to be printed in and how many copies.

Most cameras include Exif data that provides metadata about the picture. Exif data may include aperture, exposure time, focal length, date and time taken, and location.

Displaying photos

Many digital cameras include a video output port. Usually sVideo, it sends a standard-definition video signal to a television, allowing the user to show one picture at a time. Buttons or menus on the camera allow the user to select the photo, advance from one to another, or automatically send a "slide show" to the TV.

HDMI has been adopted by many high-end digital camera makers, to show photos in their high-resolution quality on an HDTV.

In January 2008, Silicon Image announced a new technology for sending video from mobile devices to a television in digital form. MHL sends pictures as a video stream, up to 1080p resolution, and is compatible with HDMI.

Some DVD recorders and television sets can read memory cards used in cameras; alternatively several types of flash card readers have TV output capability.

John McKenzie Photography - Photographer Edinburgh