The author of this example is Jean-Claude Grégoire. You can colorize this photo yourself using the half-finished materials that we give you. Download an archive containing the original image and the file with the strokes (*.strokes). Read the instruction here to see how AKVIS Coloriage works.
Jean-Claude Grégoire tells us how to achieve natural colorizations.
For this tutorial I used Adobe Photoshop and the AKVIS Coloriage plug-in.
This tutorial assumes you already are familiar with the AKVIS Coloriage plug-in, for having tried it out on a few black and white photos, because it applies to a somewhat difficult case (swimmers in a pool), and demonstrates the use of several rather advanced techniques for getting better results.
Most often, the main color of the water in a swimming pool may be blue or turquoise, depending on the color of the walls and the bottom of this pool. But, actually, there are many reflections and refractions of the light in the water, which slightly modify this main color. Furthermore, the color of the water and of the reflections and refractions modifies the color of the swimmers' skin in a variable and very subtle way. And all those color variations are a source of some definite difficulties when you're trying to colorize swimmers in a pool.
If you load several color photos in a photo editing program like Photoshop or Paint Shop Pro, and use the eyedropper tool, you'll see that the hue of one person's hair or skin isn't the same everywhere - i.e. the place of these shades on the chromatic wheel (often given in degrees from 0° to 359°, as in Adobe Photoshop, but there exist other systems) is not the same: here the hair (or the skin) will have a yellower shade, and there a redder one, etc.
So if you want to colorize hair or skin in a very realistic way, you'll have to use various hues for the hair, various other ones for the skin, etc. For example, if you download the strokes file for this tutorial, you will be able to see - when using the Color Selection Standard Dialog (see below) - that I used two different hues (H = 4° and 25°) for the hair of the child, and three (H = 0°, 15° and 22°) for the man's hair. Ditto for the skin, etc.
Some years ago I was taking color photos of some friends and of my family playing in a swimming pool. But I came to the end of my film and I had to continue my shots with a black and white one. So now, I find myself at the same time with black and white and color photos of this nice summer afternoon.
Fortunately, AKVIS Coloriage makes it possible to colorize one of these black and white photos, drawing my inspiration from the color ones. Now let's start.
The Red-Green-Blue values don't interest us for the moment, but look at the other ones, particularly the Saturation and the Value (here "Value" means "Brightness" or "Luminosity").
So, theoretically, this Color Selection Standard Dialog should help us to very easily correct a stroke which should be too little saturated (too gray), or too colored, or too dark, or to light, simply by modifying the digits in this window. The Hue is easily changed too by working on its value in degrees.
This is the theory, but in the practice, with AKVIS Coloriage, it's another story. Actually, if you read the Coloriage userguide carefully, you should have noticed the following sentences: "A light grey object from the original image can not be painted in a dark color [...] The same is true with dark areas: it is impossible to change the color of a dark area in the original image into a lighter color". It clearly means that, if you change the Value (Brightness) of the color choosen for a stroke, you won't modify the brightness of this color in the final result. But, then, what will change? Well, actually, reducing the Value of a pencil stroke will have about the same result on the colorization as reducing the saturation.
Fig. 7 demonstrates that very well.
On the left side you see red, pink and darker strokes on a grayscale in AKVIS Coloriage. The Hue is always the same: 336°, which defines a bluish shade of red.
As you can see, the Saturation and the Brightness (Value) of the strokes decrease alternately from top to bottom, and by the same value, while the other parameter remains at the highest value, on the following way:
On the right side you see the result of the colorization: it's the same for 2 and 3, 4 and 5, 6 and 7, 8 and 9. This proves that, in AKVIS Coloriage, reducing the Saturation or the Brightness (Value) has exactly the same effect.
Fig. 8 shows another interesting phenomenon: from darker to lighter, the Hue does not remain the same with every color. Particularly red (Hue 0°) and orange (Hue 30°) show some color sliding from red to yellow. Yellow (Hue 60°), green (Hue 120°) and cyan (Hue 180°) strokes give nearly black on the darkest gray stripes and cannot reach the white color on the lightest one.
These peculiarities are a very intelligent feature of AKVIS Coloriage, the result of which is the realism of the colorization.
The result is shown on fig. 10: the color of the trees, the grass, the pool and the water are not too bad. But the skin and the hairs have to be ameliorated.
As you can see on fig. 11 and yet better on the zooms on fig. 12 (both show the final stage of the strokes), the strokes in the water remind of the way the French Impressionists painted the water at the end of the XIXth century, of which I give you an example on fig. 13, which shows a fragment of a painting after the renowned work of Claude Monet "Bathing at La Grenouillère". In this work, the alternation of very contrasted colored brush strokes for painting the water is very characteristic of the style of the Impressionists.
It should be noted that one has to grope a bit for finding the best settings for the opacity of the layer in Overlay mode and for the Adjustment Layer Hue/Saturation, which can vary from one photo to another.
Fig. 17 shows the result at this stage.
If you have the possibility of working with two photo editing programs (e.g. Adobe Photoshop and The Gimp) you can open both at the same time, load the black and white photo in the first one and one (or more) color photo(s) in the other one - or vice versa. This can be useful for colorizing very large photos.
Then you'll use the Eyedropper tool for picking colors in the program which contains the color photo, and you use the Color Selection Standard Dialog in the second program for reproducing these hues by copying the digits you got in the first one.
But beware! The Hue/Saturation/Value digits are not the same in all graphic programs (*), so you have to refer to the Red/Green/Blue digits, which are always the same, from 0 to 255 for each color. Another possibility is to load AKVIS Coloriage in both programs, so you can easily use exactly the same Color Selection Standard Dialog for the black and white and for the color photo.
(*) For the Hue, some programs use the degrees (from 0° to 359° or 360°), some others use values from 0 to 100 or from 0 to 255.
For the Saturation and the Brightness (=Value), Photoshop gives percentages, so the digits go from 0% to 100%, while other programs give values going from 0 to 240 or from 0 to 255.