You've never heard of the Blend-if option - NOT surprised this is an aspect that has got past many people so your not alone!
Photoshop is a tremendously intricate and complex application, and as such, there are many ways to accomplish any specific task. The Blend If function is one of the program's more useful tools, but it is a bit hidden and does not always get the attention it deserves. This helpful video tutorial will show you five different ways to use Blend If for editing landscape photos. So go into photoshop and give this a try its a great feature
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