How should I save my files?

A tutorial for beginner level users of Photoshop.
In this tutorial I am using Photoshop CS2, a.k.a. Photoshop 9.0.2.

What a great question that is… “How should I save my files?” A more important question is “How will I be using my file?” and from there, you will know how to save it.

When saving files in Photoshop, there are many file type options. Here are some quick ways to know when to use different types:

- If your are saving your work for further Photoshop editing, save as a psd. This will maintain all of your Photoshop layers and effects. You may want to get in the habit of saving a psd first, and then the other file type you might need, in case the file needs to be altered in the future.

- If you are saving your file for use on the INTERNET, a GIF is good for line art, such as simple logos and charts, and JPG is better for files with lots of color variants, such as photos. A GIF allows only 256 colors, a jpg allows for thousands. JPG is also widely used by digital cameras. GIF and JPG files do NOT support layers when saved. Photoshop has a “Save for web” function I recommend for web files. If I should blog about that next, let me know.

- If you are saving your file for EMAIL, see above. For both of these options, a low resolution file is needed, not a high resolution file (click to read more on that here).

- If you are saving your work to share with someone who is putting your image files in a different graphics program or can’t seem to open files you send them, use a TIFF (also, TIF). These files were designed to be universally shared. TIF files DO support layers when saved. TIFF is a raster image format supported by virtually all paint, image-editing, and page-layout applications.

- If you have a text heavy document, like a brochure, or a form to fill out, save as a pdf. (But I might ask why you are using Photoshop for this file in the first place.) A pdf has the option to be high resolution, so people can later print it and the clarity will be maintained, or low resolution, for quick proofs or online sharing. PDF files CAN support layers when saved, depending on the settings you use when saving.

- If you need the file to have a transparent background, so you can put it on another background color, save as a gif.

- If you have a massive file to save - either in size or file size, choose Large Document Format (PSB) for documents of any pixel size and any file size. (All Photoshop features are preserved in PSB files.) Currently, PSB files are supported only by Photoshop CS. Photoshop Raw supports documents of any pixel dimension or file size, but does not support layers. TIFF Supports files up to 4 GB in size.

- GIFs can be saved as high resolution. They support RGB, Indexed Color, Grayscale, or Bitmap modes.

- JPGs can be saved as high resolution for print. CMYK, RGB, and grayscale images can be saved as JPGs.

What about PNG?
JPGs use compression — images are compressed to take up less memory space. Compression also leads to loss of quality. The more you compress an image, the more the quality continues to degrade. Every time you open a JPG, make a minor change, and save it, the JPG is compressed yet again. The more you work with a JPG, the worse it gets. This shows up as pixelation, overall fuzziness, random pixels are added. Also, gif creation is patented and a free option was needed. To solve these problems, a new image format was created call PNG (Portable Network Graphics, pronounced “ping.”)

PNG images are supported by web browsers and do allow for transparent backgrounds, however they tend to get fuzzy on internet explorer, which is the most commonly used web browser today, so I don’t save web files as PNGs.

PNGs do not allow for animation. If you need some slight movement, use an animated gif. An Animated gif resaved as a jpg or png will lose its animation. You can use the Save As command in Photoshop to save RGB, Indexed Color, Grayscale, and Bitmap mode images in PNG format.

What’s a BMP?
BMP stands for bitmapped graphics format. Wikipedia explains it as “used internally by the Microsoft Windows and OS/2 graphics subsystem, and used commonly as a simple graphics file format on those platforms… BMP files are usually not compressed, so they are typically much larger than compressed image file formats for the same image. As such, BMPs are generally unsuitable for transferring images on the Internet or other slow or capacity-limited media.”

A commerical printer may ask for an EPS file. Typically, these are created in vector programs, but Photoshop can save as an EPS. Virtually all page-layout, word-processing, and graphics applications accept imported EPS files. DCS format is a version of EPS that lets you save color separations of CMYK or multichannel files.

The Targa (TGA) format supports images of any dimensions with between 1 and 32 bits of color. It is designed for Truevision hardware. HUH? I don’t know either…

Wikipedia has a great chart comparing file types and what they support here: http://en.wikipedia.org/wiki/Comparison_of_graphics_file_formats