Adobe Photoshop CS5 for Photographers - Martin Evening [234]
For many years now Photoshop users have requested the ability to apply live filters in the same way as you can apply image adjustments as adjustment layers. Smart Filters is the solution the Photoshop team came with and this feature can be particularly useful when working with the blur filters discussed in this chapter, because you may very often need the ability to re-edit the blur amount. I have already shown a couple of examples of Smart Filters in use with the Spin Blur and Motion Blur filters, plus there was the example on pages 548–549 where I showed how you can apply the Lens Blur filter as a Smart Filter.
When you go to the Filter menu and choose ‘Convert for Smart Filters’, you are basically doing the same thing as when you create a Smart Object. So, if a layer or group of layers have already been converted to a Smart Object, there is no need to choose ‘Convert for Smart Filters’. You can switch Smart Filters on or off, combine two or more filter effects, mask the overall Smart Filter combination as well as adjust the Smart Filter blending options. These allow you to control the opacity and blend modes for individual filters. As I have shown below in Figure 10.8, you can also group one or more layers into a Smart Object and filter the combined layers as a single Smart Object layer.
Figure 10.8 You can make a selection of more than one layer in a document and convert these into a Smart Object. From there you can add filter effects that are applied as Smart Filters to a composite version of all the selected layers. The multi-layered image can still be accessed and edited by double-clicking the Smart Object thumbnail.
Applying Smart Filters to pixel layers
Smart Filters are essentially filter effects that are applied to a Smart Object. The process begins with converting a layer or group of layers to a Smart Object, or selecting a layer and choosing Filter Convert for Smart Filters. Smart Filters allow you to apply most types of filter adjustments non-destructively. The following steps provide a brief introduction to working with Smart Filters, in which I show how you can also use Smart Filters to apply Shadows/Highlights adjustments non-destructively.
Pros and cons of Smart Filters
The appeal of Smart Filters is that you can apply any filter non-destructively to an image in Photoshop, but this flexibility comes at the cost of larger file sizes (making the file size four to five times bigger), plus a slower workflow switching between the Smart Object and parent documents, and longer save times. This has been my experience when working with a fast computer with lots of RAM memory. This is not the first time we have come across speed problems like this. We have in the past seen other new Photoshop features that are a little ahead of themselves and we have to wait for the computer hardware to get faster before we can use them comfortably. While Smart Filtering does offer true non-destructive filtering, it is a technique you probably want to use sparingly. In this book I have highlighted a few of the situations where Smart Filters may offer some benefit, like the example shown on pages 548–549 where I blurred the backdrop layer.
1.
To apply a Shadow/Highlight adjustment as a non-destructive Smart Filter, the Background layer (or a group of layers) had first to be converted to a Smart Object. To do this I went to the Filter menu and chose ‘Convert for Smart Filters’. This converted the Background layer to a normal, Layer 0 layer.
2.
I then went to the Image menu, chose Adjustments Shadows/Highlights and applied the settings shown here. As you can see, I used the Shadows/Highlights adjustment to bring out more detail in both the shadows and the highlights. If you check the Layers panel you will notice that the Shadows/Highlights adjustment added a Smart Filter layer to the layer stack. I could now click the eye icon to switch this adjustment on or off.
3.
When I double-clicked on the Smart Filter blend options button (circled in green), this opened the Blending Options dialog, which allowed