How to Colour Your Grayscale Drawings (Student Photoshop Rendering Tutorial)

Hi Steemians, I'm back with a chunky tutorial!

Have you ever watched online tutorials where the artist will colour in grayscale (using only B/W), then suddenly 5 minutes into the video COLOUR comes out of thin air?
I have. And I have always been so confused how they did that because they never showed you exactly how. A few days ago while I was doing some concept art I have discovered the secret, the secret on how to colour like a professional artist.... And I will show you de way.

STEP 1 : INITIAL SKETCH

This is a view from inside a destroyed living room. The walls and ceilings are broken, furniture is old and dusty, and the only light is coming from the open window.

STEP 2 : COLOURS

Usually in a drawing with this kind of lighting, objects are darker as they are nearer to us. In this case, the pillars and couch is the darkest, compared to the other objects behind.

STEP 3 : BACKGROUND

The wall needed to have a gradient of black the farther it is from the open window. I also added scratches on the wall for a bit more storytelling and history behind the drawing ;) Here we can also see better that the highlights we added on the tin cans really shine against the darker background.

STEP 4 : ADDING A SUBJECT

The drawing lacked a focus, and its important that a drawing can tell a strong story. I added a rat character at the window there, looking inside the house and thinking of going inside. I also added light rays passing through the objects for a more realistic look.

STEP 5 : COLOUR OVERLAY

Ok here we're gonna get a bit technical with the Photoshop effects. But don't worry, it's really simple steps. Initially, it's going to look like this without applying the right effects. Flat colours over everything.

Aftewards go to your Layers window and select the layer with the flat colours. Make sure that layer is on top of everything else. Change the type to OVERLAY and set the OPACITY to 60% (or however much you want to put). I found 100% opacity to be too strong so I lowered it to the amount I thought looked best.

Afterwards, it's going to look like this!

STEP 6 : TINT COLOUR

Then, if you'd like a nice overlay tint to your environment drawings, you can always put a tint colour over it. Create another layer over the colours layer and fill up with the colour you want. As in, paint the whole canvas that colour (just select the paintbucket tool and click on the canvas). Put it to OVERLAY again and play around with the opacity.

And there you have it! I realized colouring this way was a huge time saver. Now you don't have to go through the whole process of selecting different colours and different hues for the colours for each object. You can just paint everything in grayscale first and put the flat colours in later. Its also a good way to understand shadows and light and how they work for different materials.