A very good artist on this website has graciously allowed me to color one of her works, confessing that she doesn't know much about coloring to begin with. This is a tragedy as her images are absolutely gorgeous. This is the piece
that I am coloring, and I decided to throw together a quick tutorial on how I did it, since it is incredibly easy. (you could probably even do this with a mouse) What makes art most visually interesting in my opinion is the range of light used, so I want to keep the original lighting intact as much as possible.
Tutorial uses Photoshop CS6, but no specific brushes and the layer types often have equivalents in other programs.
So the first step is to make a new layer above the original image and put in the "flats" or basic palette colors.
And you're done! Just kidding. Anyway, this typically works a little better if the colors chosen are more saturated than what you would see on the anime palette. I personally darken Usopp's skin to make him look more black, but avoid leaving any gray in any of this color palette, regardless of your skin headcanons. Basically, stay on the right side of the color selection square.
There's a bit of red on the skin to emphasize natural blush, and I used green to highlight the signature and make it stand out.
Next we change the layer type. Multiply and Overlay both work well for this, and if you're coloring over a lineart or a drawing with minimal shading I'd say go multiply every time. However, I want to preserve the lighting qualities, so I went with overlay. If you haven't messed with layer types, I'd personally recommend taking a look at what the rest look like sometime.
Also, with Multiply, you have to be a bit more careful coloring in the lines, so to speak. In fact, I picked the layer type before I colored so I'd know what areas I could be lazy with. Overlay changes nothing in pure black and pure white areas, so I didn't need to add color there at all.
Now this looks pretty good(referring to upper left image), I could even stop here. However, I still think the image looks a little too gray to be a proper color image. Make a new layer above the original image but below the color/flats layer, since we want to affect the original monochrome lineart, not the already bright and colorful colors. Set the new layer's type to "soft light" (though you can mess around once again with the different layer options to pick what you like best). Then fill the whole layer one color. Any color. Seriously. Here's a couple of shades of green:
I tested these two just so I could decide whether I wanted to work with a lighter color or a darker one. I went with the darker one (since I'm adding light later), but I wanted to change the color. You can do this easily by making sure you are on the layer you want to change, then going to images -> adjustments -> hues/saturation. Here are some examples of the box that pops up and the different colors I messed with:
On the left is a darkish red, and on the right is a light blue. Gives the image a different feel, depending on how you want it to look. To keep things simple, I settled on a medium brown, since that's Usopp's default color. It brings his palette together and worked well with my future lighting plans.
With lighting and color, always keep in mind complimentary colors. If I had chosen a blue hue, the best lighting choice would be orange. Red and green. Purple and yellow. You do get a bit of leeway, in that while a blue shadow could be complimented by orange, you can also branch out to orangey-red or orangey-yellow. Brown, my chosen shadow color, is a shade of dark orangey-red, so I could use any color on the scale between green and blue and get away with it. I liked the green look from before, so I went with it.
This time I went with a Lighten layer with lowered opacity. It's only a mild tinge to emphasize the lighting that's already present in the picture.
That's essentially the complete image, which i posted here
. Last thing to keep in mind I guess is layer order. Lighting layers only affect what is below them, so use wisely.