Quote - The bump map should have the tiny grooves from the smallest wrinkles. These do not correspond to color changes.

Sure, to some degree - although tiny wrinkles do tend to be a bit darker than surrounding skin if you're using photos - but all those things are going to have to be added anyway. I guess what I don't see is why you'd want to create everything (including the pores - which yeah, you can fake with some sort of noise, but my assumption is that the photos are going to provide more authentic noise than an algorithm) from scratch, and by retaining the colour map's essential features you always can readily see where you're at on the texture. Maybe that's only important to me cause I'm a rookie. :)

Here's how I've been approaching it. Maybe it's all wrong, though it seems to be working okay for me so far.

1. Save off a copy of colour map, desaturate, and get contrast and brightness where I want it.

2. With white brush (varying opacities): Neutralize spots that are dark that shouldn't be - e.g. nipples, lips, eyebrows. (Actually, in these cases, I'm going a lot further than neutralizing, as I want them visually raised, not simply level with the surrounding skin.)

3. With black brush: Draw in wrinkle lines etc. and accentuate recesses/indentations not adequately provided contrast by the colour map. (Here again to me is the advantage of the colour map - it's easy to accentuate a surface your drawing on directly.)

All my work is on separate layers so that I can adjust the relative strength (via layer opacities, in particular) of everything until I'm happy.

Now, of course, if you're going to have a lot of freckles, it's best to add those to the colour map after you've already saved off the bump map, so neutralization is unnecessary. (Natch, if pasting from reference photos with tons of freckles, something different is probably going to be required by the approach.)

As you can see, this is a lot different than just plugging a colour map into some nodes and calling it a bump map - I've got a lot of time invested in manual tweaking and adjusting.

The thing is, before I started, I looked for some good tutorials for creating bumps... but I ended up pretty much developing my own workflow, because there really didn't seem to much available saying what the best practices would be. Mostly what I read gave the principles of how bump maps work (which is relatively straightforward, ISTM), not how best to create them step by step.

As I said, this method seems to be working for me, but if there's a better way (better results, quicker process), by all means, I'm happy to learn!

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Hardware: AMD Ryzen 9 3900X/MSI MAG570 Tomahawk X570/Zotac Geforce GTX 1650 Super 4GB/32GB OLOy RAM

Software: Windows 10 Professional/Poser Pro 11/Photoshop/Postworkshop 3