Smartphones are terrific at capturing memories with the camera app. When you want to take them off the phone, or out of the cloud to create a tangible copy though, not all will translate to print very well. To avoid disappointment, it helps to know what digital image details mean so you can tell if they’ll be any good when printed.
The Meanings that Matter in Digital Photo Details
The File Type
Most cameras and the applications on smartphones default to save images in jpeg format. This is a lossy file compression method but the amount of data lost is negligible. It’s done to save on memory. The alternative file format most devices can save is RAW, which is the equivalent of a digital negative. The files are uncompressed and can have file sizes much larger than the JPEG equivalents. That’s why JPG is the standard format for images to be saved on devices, including memory cards with DSLR cameras.
The Memory Size
The memory size is imperative to know if you want to upload your images anywhere, including to order prints, or to send files to a printer or framer to be printed and framed. Most will have a maximum file size upload limit. At The Picture Gallery, our software can handle images up to a maximum file size of 20MB. That’s a lot of data for a digital image in JPG format.
If the file size of your image is too big to upload, and it’s already in JPG (meaning it’s already compressed), further compression using online tools will delete more data, resulting in a poorer-quality image. The best way to reduce file sizes is by cropping your image. That way you can be selective of which parts of the photo you can afford to sacrifice without impacting the quality of the focal point in the image.
The image dimensions display the total number of pixels contained in a digital file. For printing, you can calculate the maximum print size possible by dividing the image dimensions by the number of pixels per inch the printer is set to. High-resolution images are printed at 300 pixels or dots per inch (DPI), but still of good print quality is 240 DPI. If you want a large print that’ll be viewed from a distance where slight pixelation doesn’t matter too much, you can go lower to 100-dpi print quality.
The formula to work out your maximum print size is to divide each image dimension (length and width) by the PPI value you’ll be using. 100, 240, or 300 pixels per inch.
The MP of the Lens Used to Take the Photo
Modern phones no longer have one lens. They can have several for taking photos like a standard camera and a single lens of a different MP value for the “selfie” lens. Some phones can sport a 108MP ultra-wide lens on the front, with a backward-facing 40MP selfie lens used for taking selfies and talking on videos.
The higher the MP value, the more pixels are captured by the lens. A digital image taken with a 108MP camera lens could create a photo with dimensions of 12000 x 9000 pixels. Divide those by the 300 PPI setting for a high-resolution print, you could order a photo print up to 40” x 30”. In comparison, a 12MP digital image of 4032 x 3024 pixels would give a max print size of 13” x 10”. Lowering the PPI settings on the printer (decreasing the quality of resolution), can get a bigger print.
All other digital file details can help you observe the finer details and hone your photography skills. You can see what ISO setting was used to take the photo, the diameter of the lens the picture was shot at (13mm or 26mm ultra-wide lens), the exposure value (EV), and the shutter speed the shot was taken at. Each of these can be tweaked for future photos, but you can’t undo what’s already captured. You can learn what worked, and what didn’t, tweak your settings, and take better photos in the future.