As far as composition goes, product photography is very often center shot. The subject sits right smack in the middle of the frame with all background and foreground sacrificed to its visual presence. These center shot photos are the easiest and simplest form of composition. There's not much to say about it, except maybe, depth of field. That's not to say that all product photography is center shot. Oh no, gosh no. Banner shots, shots offset for text or human figures and shots that contain multiple product elements open the door to a greater dimension in composition.
One of the first and most important parts of a visual image composition is the entry or draw point. This is an area of the image where the viewer's perception is first attracted to and may typically be defined by a very high degree of contrast between the subject, background and foreground. Once the viewer has entered an image at this point, they are free to wander, but a good composition will provide guides to even this.
In a center shot composition, the entry point is obvious. As compositions become more complex, the entry point becomes more important.
"Three Loves of The Aviation Mechanic" is a photo of mine taken on film at Kermit Weeks Aviation Museum in Lakeland, Florida, USA.
The entry point of the photo is obvious, the high contrast bright area around the mechanic's wife. From that point, the composition features what is nearly a 2/3 Golden Rule Offset. Note that offsets do not need to be 2/3rds of the image. That's a guide, not a strict rule. The photo also features quite a bit in the way of geometric linear directions. But the really subtle composition feature in this photo is what I term 'visual cuing'.
I first became acquainted with visual cuing when reading a written description of Leonardo Da Vinci's "
The Last Supper." Each of the disciple's eyes gaze in different directions and the human response is to look to see where the disciple is looking. It is a subtle and subconscious thing. The viewer is cued to move their vision around the painting in this way.
In "Three Loves of The Aviation Mechanic", visual cuing is achieved by the direction in which the P-51 Mustang's are pointed, back toward the entry point and the mechanic's wife, who in turn, gazes up at the mechanic in one more example of cuing.
"Three Loves of the Aviation Mechanic" was a serendipity or opportunity photo. It was not posed and likely, the conditions for the photo will never occur again. Even a bad photographer can take a superior and splendid photo by serendipity and blind luck. But for good photographer's, the ability to visualize and capture such situations is a matter of training the eye, understanding the concepts of good composition.
As a last note, cropping a photo can improve composition to some extent, and "Three Loves of The Aviation Mechanic" was cropped from top and bottom.
This is about as good an intro to composition in imagery as I can provide. There is much much much more to it.
I use photographic minimalism to evaluate composition guides and train my vision. It has gotten to the point where I can easily pick out a serendipitous photo opportunity and for sure, have a great understanding regarding posed setups. Training visual perception and understanding composition are very important in that respect.