Resolution, often referred to as dpi, is a technical way of determining the definition of a picture or image. The higher the dpi the more dots the image contains per inch. The printing industry standard for image resolution is 300dpi and it is always advisable to upload photos or images in 300dpi. Most digital cameras take photos in 300dpi so uploading these images will always give you the best results. Images found online can often be 72dpi which is of low quality and will not look crisp when printed. Here is a more detailed guide on SayPrint.
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