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The author of the example is Jean-Claude Grégoire. He writes:
This tutorial was written to demonstrate the use of the AKVIS Sketch plug-in.
However, besides Adobe Photoshop, I used the AKVIS Enhancer and the AKVIS Noise Buster plug-ins.
Sometimes the photo for starting off from isn't indeed quite excellent and we first need adjustment with some AKVIS plug-ins. Yes, if the initial colors are not good enough, the final water colors won't be OK and, if there is too much noise in your photo, the sketch will not come out neat.
So I chose a bad photo to show at the same time the extraordinary photo enhancement possibilities of two other AKVIS plug-ins: AKVIS Enhancer and AKVIS Noise Buster.
This summer (2006), I took several shots of my grand children with my digital camera. Unfortunately one of them was seriously underexposed. I decided it was an ideal starting point for this tutorial.
Preparing the Photo for Conversion to Sketch
- Step 1. I load the photo in Adobe Photoshop - its size is 1600 * 1200 pixels and the resolution is 300 ppi.
Now a tip of good practice: I choose Image > Duplicate in the main menu, for getting a copy of my photo, on which I'll work, and I close the original, so that there's no danger of corrupting the original any more.
- Step 2. I call the AKVIS Enhancer plug-in (main menu: choose "Filter -> AKVIS -> Enhancer"). I get a new window with the default settings of the plug-in. I already can see an improved image but I find that it's still too dark.
So I increase the Shadows and the Lightness onto the maximum (Shadows: 100 - Highlights: 0 - Level of Detail: 5 - Lightness: 100).
I've tried to increase the Level of Detail, but I got too much noise, so I didn't. Increasing the Shadows lightens the image. On the contrary, increasing the Highlights darkens the image; so, I didn't increase the Highlights at all.
I find this image is OK. I click on the apply button what applies the correction to the image and closes the plug-in.
- Step 3. As you can see on the zoom of fig. 05, there is too much noise in the darkest parts of the picture.
It's now necessary to reduce this noise. The easiest and best way is to use the AKVIS Noise Buster plug-in. So I call this plug-in (main menu: choose "Filter > AKVIS > Noise Buster").
- Step 4. I start with trying the default settings (Automatic Filtering).
There is still too much noise, particularly on the waist of the girl.
So I modify the settings several times until I get a satisfactory image.
Then I click successively on the "Run" and the "Apply" buttons - Caution! You have to wait some time between these clicks.
I save the image under an appropriate name: it will be the base of my work with the AKVIS Sketch plug-in.
I begin the work with AKVIS Sketch
- Step 5. As I'm a cautious man, I start with duplicating the background (Ctrl+J), and activate the "layer 1" in the layers palette, so that I can work on the duplicate without loosing the original.
Now I can call the AKVIS Sketch plug-in by choosing in the main menu "Filter -> AKVIS -> Sketch".
This open the AKVIS Sketch window in which I click on the "Run" button without changing the default settings - in this plug-in, the "Run" and "Apply" buttons are exactly the same as those of AKVIS Noise Buster. As it is a big image already, it takes 1 or 2 minutes (depending on the power of your computer) for getting the result of the processing.
To compare the result with the original it's enough to left-click on the "before" and "after" tabs - the same thing if you press the tab key on the keyboard. Then you still can click in the big picture for quicker switching from one image to the other (in the small picture on the right top, this action moves the place you're looking at in the big picture). For zooming and unzooming you just have to move the slider under the small picture -you can use the usual Photoshop commands Ctrl++ and Ctrl+- too (+ and - in the numeric keypad)-, so you can easily examine the details in every part of the image.
The conclusion is that there are much too much details, particularly in the background, for a good sketch. Actually, the plug-in doesn't make the difference between what's important (the girl) and what's not (the details of the background).
- Step 6. I start with searching the best settings for the girl, without too much looking at the background.
- For getting thinner and harder strokes, I reduce the parameter Size of the strokes to the minimum.
- For getting very light midtones, I reduce the parameters Midtones Intensity and Midtones Hatching to the minimum too.
I click on the "Run" button (the processing time is much longer than the first time).
There is still too much noise, particularly about the waist of the girl (1) and on the background (2).
- Step 7. For getting rid of this noise it's necessary to introduce a bit blur in the sketch. The parameter Watercolor can easily do that, so I push its slider onto "11": the result is much better.
- Step 8. And finally I put the Coloration on "80".
I notice that the main strokes The image below shows an unaesthetic brown drawing on the lower lip and some hatching on the jaws, the upper lip, the eyes and the eyebrows, which aren't very beautiful either.
- Step 9. For getting better main strokes:
- I increase the length of the strokes to 10-17. As the drawing on the lower lip is made of short strokes, this could be a solution to this problem.
- I put the angle of the strokes to 130° and the slider Sharpen to "88".
The background isn't better at all, but the zoom confirms that the face of the girl is much better.
I apply the plug-in by clicking on the "Apply" button .
- Step 10. Now you'll soon see the advantage of having worked on the duplicate only (remember step 5). For getting the best results I'll apply a different treatment on the background than on the girl. So:
- I give this "layer 1" an evocative name: "settings OK for the girl";
- I duplicate the background layer again.
- Step 11. I now have to rework the background a little for getting a better floor. So I create on top of the duplicate an empty layer (right arrow), on which I will work.
With the Clone Stamp Tool, I copy the boards on the shadows of the floor (left arrow) and on the edge of the pool, reducing the opacity of the stamp in the right top corner. If the stamp goes too far (e.g. onto the girl's shoulder or hair), I can easily correct it with the Eraser tool, because I am working on a previously empty layer.
When this job is over, I link both layers and merge them (Ctrl+E). I give this layer an evocative name: "corrected background", and I activate it.
- Step 12. I call the AKVIS Sketch plug-in and apply the same settings as before: as the last used filter is AKVIS Sketch, I just have to type Ctrl+F and it's over (the processing can take a few minutes). The result is seen on fig. 23: the girl is still OK but the background isn't yet. So I don't apply the plugin.
- Step 13. I verify that the layer "corrected background" is still activated and apply on it a Gaussian Blur filter (main menu > Filter > Blur > Gaussian Blur) with the radius "7" pixels.
- Step 14. I call the AKVIS Sketch plug-in once again. But the settings are now the default ones (because the last used filter is another one). It doesn't matter: I try it so by clicking on the button "Run" and I finally add a bit color. Now you don't have to look at the girl, but only at the background: I find there is too much noise yet. So I put the sliders Size, Midtones Intensity and Midtones Hacking on the minimum, and push the Watercolor one onto "43" for getting more blur. I click "Run" again. The result is good but still better if I reduce the color to "29".
I click the button .
I find convenient to modify the name of the layer "settings OK for the girl" into a more simple one "girl OK".
- Step 15. Now I have 3 layers "Background", "corrected background" and "girl OK".
The question is: how shall I put the good girl on the good background? Very easily, actually. I type D to get a black foreground color. I activate the layer "girl OK" and I add a layer mask (I click on the layer mask button as shown on the picture below).
- Step 16. I type Alt+back space, and the layer "girl OK" becomes transparent (because this command calls the foreground color, which is black). Now, with the Brush Tool (default brush, opacity 100%), after typing X for getting the white color on the foreground, I make the good girl reappear. Should I go too far, it's easy to correct it by typing X for erasing my work with the Brush. If I erase too much, I type X again, and so on (look at the mask in the layers palette below).
When it's over, I flatten the image.
- Step 17. The result may seem excellent, but I find it still has a too "photographic" and quite impersonal look. I'd like to give it a more artistic and more personal look. The simplest trick is to give it more color in some places.
So I duplicate the background, I put it in Color Burn mode, with an opacity of 50%,
and add a layer mask to the duplicate, as explained in steps 15-16. Then I type Alt+back space: the color fades and, with the brush tool (after typing X as in step 16), I get some more colored areas on the drawing. I reduce the opacity of the brush for this work, here 30% (if it's too strong, I type X and erase what I've just done - see step 16). This gives nearly the same effect as adding some color in a water color, with the "wet in wet" technique (i.e. painting on wet paper).
I flatten the image.
Note: You could get the same result with the Burn Tool on the original layer, but this is more difficult, because the corrections are uneasy.
- Step 18. Now the cherry on the cake: I duplicate the background again. I activate the duplicate. From the main menu, I choose Filter > Artistic > Cutout, and I play with the settings until I get something I find beautiful. Here I chose:
- No. of Levels: 8
- Edge Simplicity: 7
- Edge Fidelity: 3
Then I click OK. I name this layer "cutout".
Note: If this filter gives an unsatisfactory result, you'll just have to try it on a bigger image. For example, if the image is 800*600 pixels, you enlarge it to 1600*1200 pixels, or more. Coming back afterwards to 800*600 pixels is always possible.
- Step 19. Now the problem is to combine this layer with the previous one. After some tests, I chose:
- Layer Mode: Overlay
- Opacity: 80%.
The final result is amazingly beautiful: I got an authentic work of art, which doesn't look like a photograph any more.
Important note: Some malcontents will probably say "You don't even need the AKVIS Sketch plug-in for getting such a beautiful image". To be honest, I've tried. Starting from the enhanced photo of step 4 I tried several Photoshop filters and merging modes on a few layers, but couldn't get the delicate result: all I was able to get was a violent image with a look of a "Photoshop processed image", unless I started a long a difficult brush work. The biggest differences of the AKVIS Sketch plug-in with the built-in Photoshop filters lie:
- in the very precise way the plug-in processes the pencil strokes for getting a realistic hand-made drawing and
- in its speed, compared with the long and numerous manipulations which are necessary to obtain a nearly similar result with the standard tools.
In any case, you don't have to be able to draw for getting an even good result as I did with the AKVIS Sketch plug-in, whereas it's quite another story with the classic filters and brushes.