Is there a way in Photoshop to apply a mask to a single Smart Filter?

Question

I like using Smart Filters because they let me adjust things later, and because I get a mask to control where the filters are applied.

The problem is that this mask applies to all the smart filters present on a given object.

Suppose I've got a photo and I want to apply the Lens Correction filter to the whole photo. On the same photo, I want to apply the Smart Sharpen filter. But I want to apply a mask to this filter. Can I do that?

Right now I've been duplicating the smart object and applying the filter I want to mask individually on to the top copy, and then masking the top copy. But this is a pain, and it takes incredible amounts of memory and disk space.

Is there a good way to apply a mask to a single smart filter?

Answer

The layer mask applies to all the filters for the smart object. However there is a workaround I've seen in a video. The below link, an article by Deke McClelland, seems to use the same trick (you create a smart object within the original smart object, so they are nested, and you then get additional layer masks). This doesn't use up a lot of additional memory or disk space

http://layersmagazine.com/nesting-smart-objects-for-multimask-effects-in-photoshop.html

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