This kind of background removal is very popular nowadays. It is not so demanding to the photography setup, you basically just put items on a backdrop and take pictures. The light is supposed to make objects contrasted with the background, at least where the shadow is not present. But in total white isolation, you have to be very careful with fur and edges all around items. And here you have to worry about the shadowless parts only.
Let's work on this bag that I already showed you. If you had to isolate it completely, this dark area underneath would be tricky to select. But as you don't have to worry about it, you can just make a crude selection with the Marquee Tool, invert it, make a few clicks with the Magic Wand and you're done. After you've run the isolating action, you'll see that the bottom of the bag is cut in a straight line, but it's really not important. What I'm going to do is grab the History brush and restore the original shadow as well as the bottom of the bag with just one well-placed Shift stroke. Remember that you can draw straight lines with any brush-like tools if you click once, hold Shift and click a second time – it will be a line from point one to point two.
Same with the boots here. Imagine how much time it would take to isolate the sole if I had to put it on a white background without a shadow. But with a shadow, it's a piece of cake. Select a rectangle, invert, click with the Magic Wand, fill the background with white and restore the shadow. Or you can Select All, Alt-select with the Marquee Tool – it will subtract the rectangle from the initial selection. Click on the rest with the Magic Wand, just watch your Tolerance setting – if's too small, it will require more clicks. Then run the isolating action and restore the shadow. Make sure your History brush tip is very soft, and be careful, or you'll leave jagged edges.
It might be more tricky if the item is not so contrasted with the background. But I assure you, if photographers do their job well, you won't have much problem even with white or shiny items. Just watch your Tolerance setting – if it's too big, the selection will reach into the item. In this case, 9 is perfect. Then again, I'll fill the background with white and restore the shadow.
Even if the image was shot in poor lighting conditions, it doesn't mean you have to use the Pen Tool to isolate it. Magic Wand method might still work, just not so well. Later, in the "Complicated isolation issues (LINK)" section I'll show you how to isolate white items that are not contrasted with the background at all. But here we're talking about isolation with a natural shadow. And I'm telling you that the easiest and fastest way to get one is to restore it with the History Brush. This simple concept somehow evades many retouchers. I've seen some tutorials online that offer you to isolate the object completely with the Pen Tool, copy it to another layer, then isolate the shadow as well and jerk both layers until you get about the same result I have in under a minute, without having to create a single layer or even touch the Pen Tool. Don't waste 5 minutes on something that can be done in a few seconds. Separating the shadow gives you more control over the final look of the image, but product image retouching is supposed to be fast. We are willing to sacrifice a lot to gain high retouching speed, and we can still make great-looking images.
You can download the images for practice purposes from the gallery above. Each thumbnail is linked to the respective hi-res image, just click on the thumbnails you need to open them in a separate window. You can right-click and "Save link as…" to download images without having to open them first.