Digital photographs are "bit images". Ceramic artists and technicians must deal with them constantly, knowing something about the subject is valuable. A bit image exists as a file on your computer or on a server on the internet. Bit images are a matrix of tiny dots (pixels) each having a color and transparency. The image as a whole has "dimensions", a 1000x1000 dot image thus has one million dots. For print purposes, a image as a whole can also have an implicit dpi "resolution" (dots per inch). The 1000x1000 dot image can be said to have a resolution of 100 dpi at 10 inches or 200 dpi at 5 inches size. Obviously, storing information on every single pixel is going to take significant memory (on your computer or in the cloud). The capicity of computers to deal with billions of pixels in an instant is a testament to their speed.
Cutting out the background on a photo
White backgrounds are used for presentation on ecommerce websites (contextual backgrounds when showing a product in use). Even if you can photograph to pure white at the edges of a photo, it will transition to grey around the object and pieces will almost always have some fuzzy edges. While there are automated edge-detection tools in editors like Photoshop or GIMP, they do not give clean edges like this. So professionals do this job using a vector-editing tool. In the past this implied learning the path tool (e.g. inPhotoshop) but now inexpensive phone apps can do it well. On the lower left is the original image (already cropped). On the lower right I have it open in an iOS app named Exacto. The blue dots are stationary anchors and the black ones pull out curves between them (curves flow smoothly through the black ones). By zooming and add/moving dots I can produce these crisp edges (Exacto saves it to iOS Photos with a transparent background). Notice how clearly the clean edges enhance the throwing rings on the right.
Same photo on my Nikon D-3500 and iPhone 8
The camera shot (top) is higher resolution, but not alot. Focus on the edges is better but I it could still be improved. But the iPhone colors are more vibrant. On the camera-shot the red, orange and yellow are washed out against the white background. Surfaces are softer on the camera-shot. I am guessing that as I learn to use the camera better it will improve. An aspect of the camera is that the screen does not have the quality the iPhone has so it is more difficult to tell if it is adjusted and focussed right.
Using a camera instead of a phone for your picture taking? Beware
Taking a picture on a modern smart phone is easy. And you can just walk over to your desktop computer and it is there automatically (e.g. for editing and uploading to your account at insight-live.com). Cameras are capable of taking better pictures, but time and dedication are required. But don't overlook the difficultly of getting photos from your camera to your desktop computer. Camera software (to transfer the data, edit photos, store and share them) is not nearly as polished a phone apps. Transfer can be awkward and glacial (e.g. 10 minutes per photo!). If you already have a camera and this is an issue, consider getting one of these SD cards (e.g. on Amazon). This turns your camera into a router/website that you access by switching your wifi to it. And transfer is fast.