Thanks for the replies.
I agree that "how to" is linked to "why" but I want to learn more than "Do X to solve Y"; I want to understand why X is better than W to solve Y.
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I also want to understand how the levels and curves truly work, as well as many other PS tools.
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I hope that the above makes sense ...
Thanks
Ok - that helps me understand what you're trying to do. It sounds to me like you've been approaching your learning in the wrong way. There are 2 distinct halves to your learning here: theory and practice.
The theory element covers things like understanding channels, colour theory, and exactly what things like "sharpening" actually are (ie - the visual effect that's taking place to make the image appear sharper). This information is not software dependent and learning this stuff will not teach you how to use Photoshop. In fact, it all pre-dates Photoshop.
On the other hand, the practice element covers learning how the different tools in Photoshop, or any other piece of software, actually work. (ie - what's the difference between sharpen, smart sharpen, and unsharp mask). This stage of learning IS software dependent because every piece of software has slightly different tools. This half will generally not teach you about the theory that a tool’s algorithm is based on.
Always remember, Photoshop is a set of tools - not a solution. There is no magic bullet. If I liken this to photography, the theory element would be similar to learning about composition and light; the practice element would be learning the different modes & settings on your camera. You need both to be a well-rounded photographer, but learning one doesn't necessarily teach you very much about the other.
To learn theory as I've described it above I'd suggest you check out Guy Gowan (
www.guygowan.com). His website contains videos explaining things like the theory behind colour switching, and why you shouldn't use S-shaped curves (spoiler alert - they create shifts in colour).
Guy Gowan does use Photoshop, but the info he teaches is not Photoshop dependent. He only uses a small number of simple tools, but by applying theory can use them in a very efficient way.
Membership to his site is about $150 per year, but he has a number of free videos which give you an idea of what’s in store. For the free videos, go to the "Focus" tab and start with video number 1.
There are other sources where you can learn all this theory too, but you need to search for the right thing – these will not necessarily be "Photoshop tutorials". I’m sure Lynda.com probably has some information about all of this, but I wouldn't expect to find it under a Photoshop heading. It’s really more to do with art, design, scanning, printing, lithography, etc.
To learn about all the very latest tools, bells & whistles in Photoshop I'd check out anything by Scott Kelby & his team – I've heard a lot of people say kelbytraining.com is one of the best learning resources for all things digital imaging and I'm sure they'll do a roundup of all the new features when a new version of the software comes out.
I’m pretty sure Lynda.com will have lots of info about the practice / tools side of things too (this time it WILL be under the Photoshop heading).
If you really do want to become an expert then I’m afraid you’re going to have to put a LOT of hours in.
Hope that helps.
Iain