With the advances in digital camera technology it is possible to get high quality images with a digital camera. However, there are a few things to consider. Three basic factors determine if an image is suitable for high quality (offset or commercial) printing: compression, resolution and file format.
The resolution of an image is very important and determines the overall quality of digital photos. Resolution is expressed in megapixels or pixels in height and width. Refer to the digital camera user’s manual to find the maximum size and resolution of images it can produce. Generally, images used for high quality reproduction/print should be 266-300 pixels per inch at the final size in which it will be used.
A note on resolution:
If your image is 3” x 5” at 300 pixels per inch – or ‘dots per inch’ (dpi) as it is referred to in print, and you need to enlarge the image to 6” x 10” for printing in a brochure, the image when enlarged to 6” x 10” will now be approximately 150 dpi – not suitable for quality printing. Simply changing the resolution of the file in Photoshop to 300 dpi will not improve the true resolution of your image. This practice is referred to as interpolation or resampling and is generally not acceptable and will result in a poor quality of the final image.
Compression also affects image quality and can destroy image data. Compressed images are generally not suitable for print. You should use a camera that supports uncompressed image data. TIFF or RAW settings are appropriate; JPEG is not. If you must use a JPEG, use the lowest possible compression setting which is the highest quality value allowed by the save dialog box. Please see example below.
When saving a file for print, use the JPEG file format as a last resort. Each time a JPEG file is re-saved, transferred or copied it loses quality and creates JPEG artifacts visible in the printed image.
