I've said it before, but it continues on. The number one keyword search bringing people to the Gallery concerns Adobe Photoshop Smart Objects. It's probably closely followed by search asking how to get rid of Smart Objects. My big question back to those folks is why do you want to get rid of Smart Objects? For those who don't want to learn about Smart Objects and want to read as little as possible... The way to get rid of a Smart Object is to Right Click on the Layer using the Smart Object (anywhere on the Layer ribbon other than the name or the thumbnail. You'll get a dropdown menu. Slide down to Rasterize Image and click. That's it. That's the way to get rid of that little Smart Object icon in the lower right of the thumbnail and revert whatever you had back to a plain old Layer. TO learn more about using Smart Objects, hit the "Read More".
If you haven't stopped reading, you're about to learn about Smart Objects. Adobe's magically way to save your butt twenty times over. Think of a Smart Object as a box that you put your image in. It has a clear cover and you can see into the box. Take a look at today's image. You can think of it as a flower, but the same thing holds true if it were a person's face. It had flaws. It was changed into a Smart Object. There are a lot of things you can do to Smart Objects that involve more Layers. You can apply filters, you can transform the image, you can add Adjustment Layers, you can composite other things onto the image. By using a Smart Object you can always get back to your original Layer.
One of the things I'd want to do at the base image (Background) is add a Layer to remove any flaws and faults on the flower of someone's face. With a New Layer selected, make sure you have Sample All Layers checked on the options bar at the top of the frame. Use whatever tool you like to get rid of the flaws. It could be the Spot Healing Brush (J), the Healing Brush (J), the Patch Tool (J), or the Clone Stamp Tool (S). Whatever your favorite tool happens to be.
If you've made other Layers and made Smart Objects from a half dozen iterations (meaning do something, make it a Smart Object, do something else, make a Smart Object of that and so on) there is one important thing to remember. How to use nested Smart Objects. It's sort of like a Russian nesting dolls. One doll (Smart Object) is inside the next all the way up to the largest.
There is a trick to using nested Smart Objects. Double click on the Layer thumbnail. That will bring you down one level. Click on that thumbnail. That bring you down one more level. Keep doing that until you get to the level where you need to work. It can be one level or ten levels. To climb back up through the levels you simply Save and Close each level. That updates the Layer above. Do not do a Save As. That'll break the chain and you'll be stuck. Just do File/Save, File/Close, File/Save, File/Close, File/Save, File/Close as many times as you need. Each sequence updates the level above it.
There is no downside to using Smart Objects. If they are used correctly. If you "break the chain" or don't go back far enough to make the correction on the proper level, it'll make you crazy and get you unbelievably frustrated with Smart Objects.
If you've ever used CTRL/ALT/Shift/E to put a composited Layer on the top of your Layer stack, kick it to the curb. Smart Objects do the same thing, only SMARTER.
Corey Barker from NAPP and Planet Photoshop just did a really good explanation of using Smart Objects with HDR, titled "HDR ToningWorkflow Tip". It works the same for any use of Smart Objects. Nice job Corey.