It’s quite common, in my group, for people to post about weird graininess in their raw files. Mostly, this is because they’ve used the stupid Adjustment Brush. More specifically, because of the "Auto Mask" function therewith.
My disdain for the Adjustment Brush goes further than the dodgy Auto Mask function, though. I am fundamentally opposed to that tool, period.
I’ve always said that raw processing isn’t really editing … it’s actually an extension of photography. The things you do in raw are the things you do (or perhaps, should have done) when you take the photo. Adjusting the exposure in raw is akin to adjusting the exposure triangle to control the light through the lens when shooting; adjusting the white balance is akin to setting correct white balance in camera; noise reduction is akin to ISO setting … do you see what I mean?
So, it’s my belief that becoming a good raw editor actually helps you become a better photographer. Consistently having to fix your exposure in raw makes you think about how you could have done it better in camera, and so on.
One of the aspects you learn about is light. How it’s hitting your subject, how you messed up, how you should position them better next time.
The adjustment brush makes a mockery of all that. You can quite easily be a dreadful raw processor, not really know what you’re doing, not be learning a damn thing about your photography, just be fixing your bad lighting with this "saviour tool".
I learned to edit raw in CS2 (I never used ACR in the first CS). It didn’t even have the Recovery and Fill Light sliders, let alone the brush. And it made me an excellent raw editor. I wish everyone was forced to learn raw processing on CS2.
Lastly … it’s just a poor alternative to the exquisite control you get in Photoshop or Elements, with layers and masks. That's where selective editing lives.
If you have a question about this article, please feel free to post it in Ask Damien.