When it comes to photography, integrity is one of the most important issues related to reputation. The term "photoshopping," or photo manipulation, is commonly used term to define the application of image editing techniques to photographs in order to create an illusion or deception (in contrast to mere enhancement or correction) after the original photographing took place. "Composite works" is using elements not present at the same time - when the photographer did not capture all of this in one camera frame - rather they put it together afterwards. Because your reputation as an artist, business person, or photographer depends on your integrity, it's important to show your work "as is" and not to try to manipulate or correct flaws of your products. Your customers are depending on a fair representation of any work you have created for sale.
There are some tools in Photoshop that can be used to naturally enhance a photo, without damaging the integrity of the photograph, and still embracing all the beauty and flaws of your products. According to the Abobe website, levels adjustment can "correct the tonal range and color balance of an image by adjusting intensity levels of image shadows, midtones, and highlights." Levels can be both manually and auto adjusted, as well as giving options to focus separately on the tone, color balance, and brightness/contrast.