Pixels and print resolution
The number of pixels and print resolution needs to be considered when determining if a file will support the print size that you want. The chart below will allow you to determine the pixel resolution required for various print sizes.
Many people think of resolution size as the “dpi” of a file, which is usually not an accurate description. The “native” resolution of your camera is usually expressed as 72 dpi. A Canon EOS D5 full-frame 12.8-megapixel sensor has a resolution of 4368 x 2912 pixels. At 72 dpi that is a very large canvas size of 60.66 inches x 40.44 inches. Expressed at 300 dpi the same file is only 14.56 inches by 9.71 inches.
A Nikon D850 sensor is effectively 45 megapixels with a resolution of 8256 x 5504 pixels. At 72 dpi thats a whopping 114.67 inches x 76.44 inches. But that’s 27.52 inches x 18.35 inches at 300 dpi for printing.
Therefore, the only “true” measure of size is the “pixel resolution”, which is expressed as the number of pixels in the length times the pixel width of the image.
How find file resolution in pixels
You can determine the pixel resolution (or actual size) by “hovering” the cursor over the file name or by right-clicking and selecting “file info” or “properties”. Some file types may have to be opened using an image editor like PhotoShop to see the pixel dimensions. It will probably be something like “3000 x 4500 pixels”. This description can be converted to various sizes at different output resolutions (see the chart below).
Print output resolution
Photo and inkjet printing typically requires the pixels resolution to be between 150 and 360 dpi at output print size. However, the limits of the camera sensor’s “native” resolution may require some additional special processing for optimum print quality. We use special software to optimize files for maximum quality.
Please let us handle this step as improperly re-sizing a file might actually decrease the quality of the final print. In the chart below, if your file’s pixel resolution appears in or is lower than that specified in the “pink” column below, please check with us before ordering.