Tutorial Gmic- Colored Pencils

Colored Pencils effect with Gimp 2.8+GmicBy: Ramon Miranda

Colored Pencils effect with Gimp 2.8 and G'MIC 2 de 9

Index of contentsChoosing the right photo or illustration......................................................................................3

Part 1...........................................................................................................................................4

Part 2...........................................................................................................................................5

Presets.........................................................................................................................................8

TIPS............................................................................................................................................8

G´MIC intro................................................................................................................................8

Conclussion.................................................................................................................................9

LicenseThis work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.

http://creativecommons.org/licenses/by-nc-nd/3.0/es/

© 2012 by Ramón Miranda. This document may be reproduced in whole or in part without permission from the author. Feel free to use this tutorial for any and all educational applications. I enjoy emails from other painters and gimp users, so please let me know if you find another uses for this tutorial.

Inquiries and comments can be directed to [email protected] This document, and other information, can be found at my webpage. Www.ramonmiranda.com

http://Www.ramonmiranda.com/

mailto:[email protected]

http://creativecommons.org/licenses/by-nc-nd/3.0/es/


We see very often that digital computer done works tend to be “too much digital” with perfect gradients and no textured look. Often, this perfection can make our works less atractive. But ,Can we have the better of both worlds? Yes, thanks to Gimp and one of his plugins G'MIC. So now we are going to simulate a very cool effect. It will produce that people feel more interested in our work.Let's get started!

The effect has two parts.

1. The Texture pass. It mimics the grain or color pencils strokes. It is made of two layers in softlight mode with 100% opacity. This way we have more control over the effect intensity. This pass musn´t be too dark or too bright. This pass makes the image usually darker.

2. Contour pass. Helps to define better the strokes and edges. We use one layer in softlight mode with 100% opacity. This pass control the overall image exposure or brightness.

Choosing the right photo or illustrationFirst of all, we need a photo or illustration to apply the effect. But What type of photo will produce better results? That is a good question, because sometimes we don't get the best results and we can´t say that the photo or illustration is the reason of that. Maybe we have choosen a “bad” photo for the effect. In this case, we get better results with not too much contrasted photos because the softlight mode changes the local contrast. Also, if the photo has too much detail we can apply a light “blur” with Filter/Blur/Blur

The photo used here shows the tipical “still life” with warm tones. These type of images are very useful to study the light behaviour and are very easy to compose with basic stuff like drapes, fruit and cans. I tried to use old fruit because it has more texture and more colors, This is a more real approach and is beauty.

Figure 1.1


Part 1.The first step is to apply a “texture pass”. We duplicate the background layer. This way we have a back up of the image. We select the menu Filter/G'MIC. We find it at the end of the filter list. Once selected, G'MIC opens a new dialog where we can see different areas with lot of parameters. If you never have used G'MIC you can go to the G'MIC intro section for a quick intro. If you know how to use G'MIC you can continue reading.

We search the Black & White / Hard Sketch filter and Adjust the settings as in figure.

We click on Accept to apply the filter and we see an image like this.

Figure 1.2

Figure 1.3


At first view is something weird, but we can fix it easily changing the blending mode from normal to softlight. We duplicate this layer to increment the effect. Now we see a texture that covers all the image.

We may think.. Why we duplicate the layers if they share the same blending mode? Wouldn´t be better to combine both layers and adjust the overall effect using curves? Not in this case.And what if we duplicate the layer again? Well, we'll get an incremental effect.(possibly too much)

Surrounding the glass-can we see radial lines that maybe you like or not but they are inherent of the use of G'mic filter hard sketch. These radial lines appear when there are long lines in the main image. Sometimes contribute to the image improving it. sometimes not. We can control a bit this “artifact” using layer masks.

Part 2.The next step is create a contour pass. This will help to balance the contrast and brightness on the image. Also makes the edges more visible.We duplicate the main layer, the layer with no effects and we put it over the rest of the layers. We go to Filter/G'MIC. There we select again the hardsketch filter. We need now to adjust the parameters to obtain edges so we put the values as we see in the following figure.

Figure 1.4


We click on Accept and we change the blending mode from normal to softlight. This makes the contours more marked and also generates an outline in the highlights as we see on the figure. Darker parts now tend to be brighter washing the blacks in the image.

Figure 1.5

Figure 1.6


Tip: If you apply a contour pass and you see image becames too bright go to Colors/Curves and adjust the graph as you see on the following image.

Now we have all the layers available to be tweaked. This give us a lot of control. We can change each layer opacity and blending mode to see different effects. For example we can make another duplicate from the contour pass and change the blending mode to “grain extract” . This way we can remove the outlines or create interesting creative effects.

Figure 1.7

Figure 1.8


PresetsWe can store presets inside G'MIC. This way, we can create presets for the “texture pass” and “contour pass” Once created, they will appear in the favourites section in the upper part of filter list. To create a preset we need to adjust the filter parameters as we want and then click on “+” symbol. This icon is placed on the bottom part of the filter list.

TIPS• Works better with not too much sharpened images.• Works better (faster) with image size about 1000 px (the longer side)• Don´t use the magnifier inside g-mic for this filter in the preview window

G´MIC intro Basic explanation of G'MIC plugin

1. Preview area for the selected filter.2. Input/Output area . This tells G'MIC where to apply the filter. And which layers are taken

into account to compute the effect.3. The filter list.It has several cathegories.4. Filter parameters area.5. This is the place were we choose between some options related with the selected filter:

◦ Quits G'MIC without applying the filter◦ Reset the selected filter◦ Maximize the area that G'MIC ◦ Apply the filter without quiting G'MIC. This allows us to select another filter and link

filters without quiting G'MIC◦ Accept the selected filter and quits G'MIC

Figure 1.9


ConclussionIs that all? No way, we have only explored a filter and a blending mode. Possibly all this process can be converted into a new filter with some options. So i encourage you to share your experiments and improvements by mail or in my blog. It would be nice if you thank also David Tschumperlé for his work with G'MIC.what a great project, to be suported! I hope you liked this tutorial. Bye and see you next time.

Documents

Tutorial Gmic- Colored Pencils