I was actually talking about the non-scope method, Derrel. But I don't have any problem with either (that's silly).
I was saying that you can use the f/22, OOF, etc. method in the field, because there's no need to use a laptop with photoshop levels, since you don't do photoshop levels to your photos either. You can just snap the photo, look at the image on the LCD, clean, snap another photo and preview all in camera and vastly faster than trying to use some ridiculous laptop method.
...Or a scope. I'd probably actually lean slightly toward the "take a photo" method versus the scope, simply because what you intend to actually do is to take photos, so it gives you a better idea of what dirt actually matters. Like, if there's residue you can see with the scope but not in a photo, then you don't really need to spend time or any risk to clean the residue, but you might not know that you don't if only using a scope. But whatever, who cares.