.PNG files in logo design and when you should use them
PNG is an acronym for Portable Network Graphics. PNGs are bitmpapped (raster/pixel based) image formats that can be used instead of GIF images or JPGs. PNG logo images are superior to other pixel based formats as they employ a ‘lossless’ data compression system. We’ll use the logo for Big Island Color, as developed by The Logo Factory, for illustration purposes.
PNG colors are palette-based (8 bit, 24 bit RGB or 32 bit RGBA colors), greyscale, RGB, or RGBA. The higher the bit rate, the larger the file size with increased download time. 32 bit images are not recommended for most website applications. The PNG format was created specifically for use on websites and in browser based e-mail and cannot be used in traditional offset printing (PNG formats do not support either spot color or CMYK four color spaces.) When using JPG images, there are some issues with certain colors previewing correctly (reds are particularly bad for this) and using a PNG format can fix that nicely.
Transparent backgrounds. Use on any color.
One of the main advantages of a PNG formatted logo is the ability for the image to have a transparent background, unlike JPGs which do not feature transparency (requiring a background color for its ‘bounding box’), and a superior alternative to GIF images which do, but sacrifice a substantial amount of image integrity to do so. PNG format also features Alpha channel transparency (the ability to turn off the complete background surrounding a logo image, or to make the image transparent to various levels ie: drop shadows) which is more adaptable than index transparency (the option to turn one color off). Earlier versions of Microsoft Explorer had some issues with previewing PNGS with a Alpha channel transparent background, but there are code fixes available to address the problem. About 90% of the images featured on our website are in PNG format.