gimp part6 jan 2009

8/8/2019 GIMP Part6 Jan 2009

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ver since the invention o thecamera, people have beeninquisitive about photography.

However, not even the bestphotographers get the results they aim or,every time. o err is human, isn’t it? Tus, inorder to achieve a perect blend o lightingand range, photographers thrive on photomanipulation sotware. Te GIMP providesa wide range o tools and utilities to x yourphotographs and you will be enthralled withthe results. Te only downside is the lack o a32-bit high colour channel. Apart rom that,the GIMP is the perect tool to x images.

In this tutorial, we will work on some

cool techniques that are oten used by photographers in order to stun viewers. Teefects sure look gorgeous, while achieving

that look with the GIMP is child’s play. Inthis tutorial, we will explore three diferentefects—HDR (High Dynamic Range) efect,

Mask Isolation (a la the Sin City efect), andthe Stamp efect (I like to call it that). So, let’sget started.

The HDR effectTe digital rendering o HDR increasesluminance o the darkest and the lightestpart o a photograph or an image. Te HDRefect adds to the beauty o an image by providing more depth to it. But beore weproceed, we need to install a plug-in namedDodge and Burn. Grab the plug-in rom the

LFY CD and copy it in the ~/.gimp-2.6/scriptsolder. Restart the GIMP and you should havea new menu named Script Fu.

Welcome to the sixth instalment of tutorials on the GIMP. In this article, we will

focus on improving photographs and images by using an array of effects.

GIMP for Beginners, Part 6

Souping Up Photos

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8/8/2019 GIMP Part6 Jan 2009


o begin with, open any image you want to beautiy with the HDRefect. For this tutorial, I am usinga dull wallpaper o a pyramid that’sbeen languishing in my collection o wallpapers.

Step 1 Open the image in the GIMPand duplicate the background layer.

Step 2 Select the newly createdlayer and desaturate the layer usingColors→ Desaturate, with ‘Average’ asthe desaturation mode.

Step 3 With the same desaturatedlayer selected, invert the colour romColors→ Invert . Inverting the colour

gives a more striking appearance.

Step 4 It’s time to add moreluminosity to the image. Head to

Filters→ Artistic→Soft Glow . Withdeault settings, apply the efect.

Once you have applied the efect,the image turns bright and shining.Tis does hurt the eyes and is toobright or our HDR efect. So we willtone the efect down by reducingopacity and changing layer modes.

Note: Te efect or the top-most layer will be morepronounced. Tus, in order toshow/introduce an efect, move thedesired layer to the top position orchange the layer mode o the top-most layer.

Step 5 Once you have applied theefect, set the layer mode to Sotlightand reduce the opacity to 50.

Step 6 Duplicate the same layer andset the opacity to 75.

Te lighting is still too bright andthere is no sign o dynamic darknessin the image. Since HDR is about bothdarkness and luminosity, we need tocast a spell o some dark magic as well.

Step 7 Duplicate the bottommost/source layer and drag it abovethe rest.

Figure 1: HDR effect in action

HDR Effect (High Dynamic Range)

Figure 2: Isolating using mask

Isolating object using Mask tool

Step 8 Navigate to Color → Levels and set the rst output level to 100(as shown in Figure 1). Tis turns the

image to severe black, which is notour cup o tea either. So, we will tonethis down as well.

Step 9 Set the layer mode o thetop-most layer to ‘Darken Only’ andreduce the opacity closer to 45.

We are almost done. Just rightclick on the layer and select ‘Merge all

visible layers’. With deault settingsselect ‘OK’. Now, here is when theDodge and Burn plug-in comes into

play. We will be needing it to addmore depth and make the imagestand out rom the background.

Step 10 Head to Script-Fu→

Enhance→ Dodge and Burn. Changethe thin amount to 10-15 depending

on personal taste and apply it.Notice that the efect adds twonew layers to the image. We don’thave to bother about them. Just selectthe base image and its time to add thenal ingredient.

Step 11 With the background layerselected, navigate to Color → Hue

Saturation. Increase the saturationway up to 50-60, depending on thebrightness you are looking or.

Tat’s it! We have created acool efect, making the image more

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8/8/2019 GIMP Part6 Jan 2009


around stamps have alwaysattracted me. Ever since I laid my hands on the GIMP, this was theeect I tried to come up with.

For the stamp efect, we will beeyeing the Quick Mask tool. You can

activate Quick Mask rom Select →Quick Mask.

So, let’s gets started. As always,open an image, select the rectangleselection rom the toolbox and createa big selection.

Step 1 oggle Quick Mask by pressing Shift+q.

Step 2 Navigate to Distorts→ Ripple,with Period, Amplitude and Phase

shit settings as 15, 3, 0, respectively. Apply the efect, both horizontally and vertically, one by one.

Step 3 Undo the ‘Quick Mask’ by pressing Shift+q. Notice that as soonas you remove the Quick Mask, theGIMP rames the selection into anactive selection.

hus, rom here, you caneasily make a postcard or stamp.

Just copy and paste in a new template. Change the transition to‘permanent’.

Once done, right click on thenew layer and select Alpha toSelection. Navigate to Select →

Borders and, with 1 as radius, apply the border. hat’s it — just add theblack colour to the border! Add aew other eects here and therei you want to and you will havecompleted the stamp eect as well.

Phew! Tat sums up the sixthinstalment in our series on the GIMP.In the next tutorial, we will unravelthe wallpaper using the Path ool.Tis is one o the most versatileefects that gels with various shapesand is used oten by many graphicgiants. ill then, stay tuned and haveun GIMPing.

Step 4 Add a mask to the layer.

Right click the ‘Mask Layer’ and adda white mask ( ull opacity).

Notice that any drawing orediting done rom now on appendsto the Mask Layer.

Step 5 Grab any brush and, withblack as the FG colour, apply thebrush to the part that you want toisolate.

Zoom in, and increase/decreasethe brush radius in order to achievea perect efect with no distortionor abnormalities. Now apply thebrush only to the object you want toisolate/colour rom the desaturatedbackground.

I you erred and coloured theouter periphery, then you caneasily undo it by pressing Ctrl+z orchange the oreground colour towhite and use the paintbrush inthe undesired area. White restores

and black erases the portion whenapplied in the mask. Another cool efect completed in

a ew steps!

The stamp/postcard effectI always had an ainity towardsstamps and postcards. heirdesigns and the zigzag edges

pronounced by eliminating dull and

imperect lightning. What are youwaiting or? Give it a try :-)

The Sin City effect With reference to what we learntin the fifth assignment in thisseries on the GIMP, this effect isin its own league and has nothingto do with any selection tool. Thename ‘isolation’ is a bit odd for thiseffect since we are not actually extracting any part, in any way. Tobe precise, this tool makes a partappear more highlighted, like inthe Sin City movie.

Although the Sin City eect is alittle diicult and complex, the pathis the same. Grab any image andopen it (in the GIMP, o course!). Forthis tutorial, use objects like a car,truck or any thing big that can behighlighted.

Step 1 Duplicate the backgroundlayer by right clicking and selecting‘Duplicate Layer’.

Step 2 Rename the layer to ‘Mask Layer’ by right clicking and selecting‘Edit Layer Attributes’.

Step 3 Select the newly createdlayer and desaturate the layer romColors→ Desaturate, with ‘Lightness’as the desaturation mode.

Once you have desaturated thecloned layer, it’s time to get movingwith the mask.

By: Shashwat Pant

The author is a FOSS/hardware enthusiast who likes to review software and tweak hishardware for optimum performance. He’s interested in Python/Qt programming, and

fond of benchmarking the latest FOSS distros and software.

Figure 3: The stamp effect in GIMP

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gimp part6 jan 2009

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