In Photoshop CS3, non-destructive editing allows an analyst to try all sorts of effects and and get really crazy without modifying the original image. The preservation of the original file has always been the key in our line of work. You can use non-destructive editing in many different areas of Photoshop CS3. These include transforming with Smart Objects (new), global filtering with Smart Filters (new), adjusting lighting using shadows and highlights with Smart Objects (Yay!)(new), editing in Camera Raw (tiff and jpeg are new), adjusting variations with Smart Objects (new), opening Camera Raw images as Smart Objects (new), and the old standards like masking, and using adjustment layers. But be warned, there's one thing about Smart Objects and layers that might catch you off guard when you first add this to your work flow; if you duplicate a Smart Object (as in layers), Photoshop only stores the original source data whilst creating a second copy of the composite data. Thus, when you edit a Smart Object, Photoshop updates all copies. Why?
A Smart Object can be thought of as a container that holds raster or pixel image data from another Photoshop or Illustrator file (much like an AVI is really a container that holds multimedia data). It retains all its original data and, using the composite data, remains fully editable. As you are working on composite data and not original data, a Smart Object can thus be edited non-destructively in Photoshop without effecting original image data. Another way of looking at it is to say that Smart Objects store source data with the original object, so you can work on a copy of the image without changing the original—one file embedded within another.
Using Smart Objects in your image's layers wouldn't be of much use if you couldn't apply filters to them. When you apply a filter to a Smart Object, the filter is transformed into a Smart Filter. Adjustment layers stack above the layers that they affect. Smart Filters show up in the opposite way, appearing in the layers palette below the Smart Object layer. Like adjustments layers, you can show or hide them independently and they are nondestructive. So, if they are just like adjustment layers, only they stack down rather than up; what's so special about them? With Smart Filters, you can apply any filter, except Extract, Liquify, Pattern Maker, and Vanishing Point as a Smart Filter. Yes, this means Shadows and Highlights becomes a non-destructive Smart Filter option! I can hear the cheers erupting.
If you are a regular visitor to my blog, this will be the last post until I return from Calgary next week. Thanks for your support. Be well and stay safe.