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from Maximum PC by Paul Lily

10 Sweet GIMP Photo Editing Tricks to Wean You Off Photoshop

from Maximum PC by Paul Lily
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You could buy a used car -- albeit not a very good one -- for the same scratch it takes to pick up a copy of Adobe Photoshop, the de facto standard in high-end photo editing software. Or a pair of GTX 285 graphics cards for that killer SLI setup you've always wanted. We could go on, but at $700 for a piece of software, Photoshop's MSRP hardly needs put into perspective. In short, it's expensive.

It's also powerful, but don't worry if you don't have a handful of Benjamins lying around. Thankfully, you can perform a lot of the same photo editing tricks for free with GIMP. Short for GNU Image Manipulation Program, GIMP is the open source (and no-cost) equivalent to Photoshop, and like it's paid counterpart, GIMP can be a little overwhelming at first. That's where we come in.

Like swimming, it's best if you just dive in. To help give you that push, we waded through the gazillion tutorials floating around the Web and brought back a sundry collection of groovy tips and tricks that, along with some touches of our own, will have you learning the ins and outs of GIMP while having fun doing it. We'll show you how to make lifeless photos pop with detail, how to tap into the Force and add a lightsaber to any pic, make your own custom brushes, and much more.

Be More Efficient with Batch Processing

After spending hours resizing and making minor adjustments to each of the hundreds of photos you took on your last vacation, you vowed to be much more seletive in what shots you take the next time you go on a trip. But you knew it was a promise you'd never keep, and that's okay, because even though GIMP doesn't come with a built-in batch editing feature, there's a plugin available that will add that functionality.

The plugin you're looking for is called David's Batch Processor (DBP), which you can download here. Scroll down to the Windows Users sections and grab the latest download (dbp-1.1.8.zip). Extract dbp.exe from the ZIP file and place it in C:\Program Files\GIMP-2.0\lib\gimp\2.0\plug-ins. That's all there is to it!

The next time you fire up GIMP, you'll find the Batch Process feature under the Filters menu. If you don't see this option, make sure you put the plugin the correct folder and reload GIMP.

The Batch Processor window contains several tabs, but the first thing you need to do is click on Add Files and select the photos you want to alter. You can remove individual files if you accidentally add one or change your mind, or clear the entire list.

We tend to take high resolution images, which gives us the flexibility to come back later and edit them for different projects. But this also makes them unwieldy to send to friends and family who have no interest in downloading a 10MB attachment. We can rectify this by selecting the Resize tab, clicking on the Enable checkbox, and then choosing whether to downsize by Relative or Absolute.

Other options include the ability to turn, flip, and rotate images, blur photos, adjust the color (including auto adjustments), crop, and sharpen. We can also choose to rename our snapshots and output to a variety of file formats, such as BMP, JPG, PNG, and several others.


Sharpen (Literally) Your Photo Editing Skills

Ever wonder how pro photographers manage to make their photos look better than the real thing? Part of the answer lies in post processing. Of course, adequate lighting, a good camera, and experience all play a part as well, but you can clean up almost any photo with just a few simple steps.

Snapshots of electronics clean up particularly, allowing you to post lust-worthy pics of your setup on your favorite computer forum or auction site. For this example, we're using an image of an EVGA X58 Classified motherboard. The colors appear a little dark and lackluster, so we're going to address that first.

Navigate to Colors and select Levels. You'll notice a histogram, which tells you how the pixels are distributed. If most of the action in the histogram is to the left, then your image is probably dark and underexposed. If they're to the right, then the picture may be too bright. A perfect shot will show most of the action in the middle.

What we want to do with this photo is lighten it up and get rid of the haze. Click the triangle on the right side of the graph and move it left. Keep doing this until the colors start to go out of whack, then back off slightly. When you're finished, make sure the image is noticeably brighter than when you first started. For this example, we decreased the white level from 255 to 222.

Now that we've lightened the image, it's time to make it pop. To do this, navigate to Filters>Enhance>Sharpen. The more you sharpen the image, the more lively it will look, but be careful not to overdo it or you'll end up with a swirl of colors. We settled on a value of 60, which over exaggerates the details - just the effect we were going for!

While this trick doesn't always work well with text-heavy photos or screen grabs, it does do a good job with outside scenes, especially where vibrant colors are involved, like a blue sky or lush vegetation. Notice in the above photo of our workplace how the right side -- the side we cleaned up -- looks much less blurry and vibrant than the untouched left portion. If you look close enough, you might even spot Wil giving an intern a verbal lashing - a typical Monday morning!

Make Your Own Custom Brushes

GIMP comes with a variety of brush styles to choose from, including various sized circles, splatters, and even a green pepper, but you can create any style brush you want. Here's how.

First, create a new transparent image sized to however large you want the brush to be. In this case, we're going to create a 70x70 image. Paste or draw whatever you want the brush to be (we used a cat's paw). Duplicate the layer (Layer>Duplicate Layer) one time for each color you want to use, then use the Paintbrush or Bucket Fill tool to make the image a different color in each layer.

Now comes the semi-tricky part. Because we're using four multicolored layers, we want to save our image as an animated brush. Save your image using the .gih file format, and in the 'Save as Brush Type' dialog box that appears, change the Ranks number to 4, or equal to however many layers you created.

Save or move your newly created brush to C:\Program Files (x86)\GIMP-2.0\share\gimp\2.0\brushes. No need to close and reload GIMP - just click the Refresh brush button in the lower right corner of the brush menu and you're good to go!

(Credit: Gauntam Lad


Wield a Lightsaber Like Luke Skywalker

In a perfect world, we'd all have lightsabers and settle our disputes like they do in Star Wars. While technology is probably still a few years off from perfecting the lightsaber, we can at least fake it in our photos, and all it takes is a little bit of editing..

It's helpful if you start off with a picture that already has a sword, stick, or other similar object in it, though this isn't required. For our example, we're going to alter a snapshot from Medieval Times.

After you've selected and opened the photo you want to modify, create a new layer with a black background. To do this, select Layer>New Layer, or press Shift+CTRL+N. Where it says Layer Fill Type, select Foreground or Background color, depending on which one you have set to black.

Highlight the new layer in the Layer Console window and change the Mode to Screen, as shown above. Once you do this, you should be able to see your original photo. This begs the question, 'why not just create a transparent layer?' We tried doing that, but were unable to change the color of the lightsaber (which we'll get to in a bit). For an in-depth explanation on the different layer modes, see here.

With the black background layer still highlighted, click on the Paths Tool in the Toolbox window (second row, third icon). Use this tool to create a selection around the object you want to transform into a lightsaber (you may find it helpful to zoom in on your image while doing this). In our example, we're going to outline the sword's wooden blade.

Once youv'e made an outline, navigate to Select>From Path, or hold Shift+V to activate your selection, then use the Bucket Fill Tool or Paintbrush to completely fill in the selection with white. When you're finished, deselect the object by going to Select>None.

Next, create three duplicate layers (Layer>Duplicate). You should now have five layers total - your original picture plus four black layers.

Highlight the top layer, then navigate to Filters>Blur>Gaussian Blur. Change both the horizontal and vertical values to 5. When you're finished, repeat the same step for the second layer, but change the values to 10. Repeat again for the third layer and change the values to 20, then one more time on the fourth layer and change the values to 40.

By this point, your object should look like a lightsaber, but we're not finished yet. Right-click the top layer, select Merge Down, then change the Mode to Screen. Repeat this step two more times so that all you're left with is the original picture (bottom layer) and a black background layer with a white lightsaber (top layer).

At this point, you're ready to customize your lightsaber. With the top layer highlighted, go to Colors>Color Balance and adjust the sliders until you're happy with the result. For an added effect, click the Shadows radio button and adjust the sliders some more.

(Credit: gimpology.com)


Create a Swirly Wallpaper or Water Drop Effect

Grown tired of the stock wallpaper that ships with your OS? You can hit up Google Images until you stumble upon one that fits your mood, or better yet, create your own one-of-a-kind wallpaper. Forum member acm321 on CrystalXP.net came up a easy-to-learn technique for making swirly wallpaper using GIMP, and we want to expand on that. Here's how you do it.

Decide what resolution you want your wallpaper to be. For this example, we're going to create a background that measures 1680x1050. Open a new image (File>New) sized to whatever resolution you're running, or go even larger if you think you might upgrade to a bigger LCD down the line.

Pick out a color and then choose a dark shade for the foreground and a light one for the background. You can change these by clicking on the two squares in the middle of the Toolbox window (if you need help choosing contrasting dark and light colors, see here). In this example, we chose Firebrick3 (#C11B17) for the foreground and Red1 (#F62217) for the background.

Click on the Blend tool in the Toolbox and verify that the Gradient is set to FG to BG (RGB) and the Shape set to Linear. With the Blend tool, draw a line from the top to bottom, bottom to top, or from corner to corner.

Change the foreground to white, then draw a swirl in the middle of your image using the brush tool. Don't worry if the swirl isn't perfectly uniform.

Next, navigate to Filters>Blur>Gaussian Blur and set both values to 40, then hit OK. You should have an image that looks similar to the above.

Navigate back to the Filters menu and select Distorts>Whirl and Pinch. Crank the Whirl angle slider all the way to the right and the Pinch amount slider about three-quarters to the left. Leave the radius at 1.00..

Go back into the Filters menu and select Distorts>Waves. Make sure that the Smear radio button is selected. Play around with the amplitude, phase, and wavelength sliders until you're happy with the result (for our image, we set the amplitude to 75, phase to 140, and wavelength to 45).

We're almost finished, but first, we want to make the ripple effect stand out a bit more. Go to Filters>Artistic>Softglow and adjust the sliders to your liking. For our finished image above, we set the Glow radius to 1.00 (move the slider all the way to the left), Brightness to 0.25, and Sharpness to 1.00 (move the slider all the way to the right).

And that's it! If you're not happy with the color, there's no need to start over. Instead, go to Colors>Hue-Saturation and adjust the Hue slider.

When you're finished, play around with the other filters and see what different effects you can come up with (Hint: Go to Filters>Render>Clouds>Difference-Clouds).

(Credit: CrystalXP.net: acm320)


Create an Explosion in Outer Space

With a little bit of creativity and experimentation, the sky's the limit with GIMP. And so is outer space. By using a pre-rendered scene included in GIMP, we're going to create a galactic explosion.

Create a new image any size you want. Navigate to Filters>Render>Fractal Explorer. Click on the Fractals tab, highlight Snow_Crystal, and click Apply.

We want to blur the image so it no longer resembles anything like a snowflake. Go to Filters>Blur>Motion Blur. Change the Blur Type to Zoom, check the Blur outward checkbox, and adjust the Length slider all the way to the right. Click OK. On older machines, this may take awhile to process, so be patient.

Duplicate the layer (Layer>Duplicate Layer), then flip it vertically (Layer>Transform>Flip Vertically). Change the Blend mode to Burn.

We now have the basis for our explosion, but we still need the bright burst of light. Create a new layer with a black background, change the mode to Addition, then navigate to Filter>Light and Shadow>Lens Flare. Place the flare square in the middle, then repeat this step and place another flare slightly off to the side.

Create a new layer with a black background and change the mode to Addition. Change the foreground color to yellow, then click on the Paintbrush tool and select the Galaxy brush. Add several splatters in an uneven circle around the bright flares.

Now go to Filters>Blur>Gaussian Blur and change the values to 15. We now have a realistic looking explosion! Splatter the scene with different sized stars using the brush tool, and add whatever else into the scene you want (planets, asteroids, spaceships, etc).

(Effect Credit: gimp.pixtuts.com)


Convert Photos to Sketches (without a Plugin)

Not all of us have an inner Rembrandt to work with, but we do have a PC. As it turns out, that's all you need to make realistic looking sketches, which you can then hang on the wall and dupe visitors into thinking you're a virtuoso with a pencil, or print out for your kids to color. But be warned - we've added some steps that were left out of the original tutorial and there isn't much room for error, so follow along closely.

Pick out a photo and open it in GIMP. Try to avoid overly cluttered backgrounds, as they end up difficult to discern when converted to a sketch.

Navigate to Filters>Edge-Detect>Sobel. Make sure all the checkboxes are selected and hit OK. It may look like we just irreversibly ruined the image, but rest assured, we're just getting started.

We need to highlight the details, and to do that, go to Colors>Auto>Equalize. Because we want a black & white sketch, we now need to get rid of the colors that were just drawn by converting them to gray. To do this, click on Colors>Desaturate and hit OK.

Create a duplicate layer (Layer> Duplicate Layer, or press Shift+CTRL+D). To make things easier as we go, double-click the original layer (the one in the bottom on the Layers panel) and rename it 'Equalized Layer.' Now double-click the layer you just created (the one on top) and rename it 'Highpass Filter.'

Nw we need to bring out the details of our sketch-in-progress. Part of this entails darkening the blacks and lightening the whites, and there's two ways you can go about doing this. The first is by going to Colors>Levels and adjusting the Input Level sliders until you're happy with the results. Alternately, you can apply a high-pass filter using GIMP's Curves tool (Colors>Curves).

No matter which one you use, the finished product should look the same, as depicted above.

Here's where things get a little tricky. Make a duplicate of the Equalized Layer by clicking on it and selecting Layer>Duplicate Layer. Move this layer to the top (click and drag), double-click, and rename it 'Masked Layer.'

We need to invert the colors on this new layer. Click on the newly created masked layer (which should be on top), and select Colors>Invert.

Next we're going to apply our highpass layer as a mask. Highlight the Highpass Filter layer and select Edit>Copy. Now highlight the Masked Layer that you just inverted, right-click, and select Add Layer Mask. In the dialog box that pops up, check the Selection radio button, then press Add.

If you followed the steps correctly so far, your Layer box should look like the above. Select the Masked Layer you just created and click Edit>Paste. Right-click the 'Floating Selection' layer that appears in the Layer box and click Anchor Layer.

You're almost finished! For the last step, you need to create a new, white layer (Layer>New Layer), then drag it underneath the Masked Layer. If you didn't make any mistakes, your sketch should look similar to our example.

If you want your sketch to show more details and shading, play around with the input levels or curve tool when manipulating the high-pass filter and lessen the black level, allowing more highlights to show.

(Credit: Dave Neary)


Mix B&W with Color

Some of the best looking effects are also the easiest to pull off, and that's definitely the case with this one. All that's required is a bit of patience and a whole lot of experimentation.

There's no hard and fast rule that says one type of picture will end up looking better than another, but generally speaking, you want to start with one where the main character or object is vibrantly colored.

Once you've selected a photo and opened it in GIMP, duplicate the layer (Layer>Duplicate layer). We need to remove the color from this duplicate shot, and do that, navigate to Colors>Desaturate. You have three options to choose from -- Lightness, Luminosity, or Average -- each one representing a different shade of gray. We chose Luminosity for our example, but use whichever one you like.

Now you should have a black and white layer on top of the original color photo. Right-click the top b&w layer and select Add Layer Mask. Select the White (full opacity) radio button and hit Add.

Now you're ready to start restoring color. One way to do this is by simply grabbing the brush tool and going to town willy-nilly, but we found it easier to zoom in and create a selection path around our area of focus. Once you're zoomed in, select the Paths Tool and create points all around the area you want to color. Then choose Select>From Path or press Shift+V to make the selection active. Now you can restore color using the paint brush without fear of accidentally spilling into other objects.

How much or how little of the picture you want to restore is up to you, but it doesn't hurt to play around (just keep pressing CTRL-Z to undo each step if you don't like the result). In our example, we partially restored an outline in the grass for a natural border..

You'll often see this trick applied to flowers and plants, but don't be afraid to experiment with different types of photos and see what you can come up with!

(Credit: Eric R. Jeschke


Convert Photos to Neon

There are a billion and one tutorials on the Net that show you how to convert text into neon in GIMP, but not many tell you how to convert an image. In fact, we only found one, and it was missing some critical steps. Here's how you can create a neon effect from any photo without pulling your hair out.

This works best if you pick out an image where the person you want to crop isn't just standing upright. Once you've found a suitable candidate, zoom in, select the Paths Tool, and create an outline around the subject. Don't worry about making it perfect, we just need a general outline. Click on Edit>From Path to activate the selection, then copy it to your clipboard.

Open a new image with a black background, then select Edit>Paste as>New Layer. Now click on Layer>Transparency>Alpha to Selection. If it isn't already, change the background or foreground to white then click Edit>Fill with BG Color (or Fill with FG Color, whichever one is white). You should now be left with a black background and a white image of your selection.

Now click on Select>Grow and choose the value 1 where it says 'Grow selection by.' Click OK to get rid of the dialog box, then hit the DEL key. Next, navigate to Edit>Stroke selection (make sure white is selected as your foreground). Chose 2.0 for the line width and make sure the Solid color radio button is selected, and then click on Stroke.

Next, click on Layer>Transparency>Alpha to Selection, then duplicate the layer (Layer>Duplicate Layer). Now click on Select>To Path, then Select>None. Duplicate the layer again, then go to Filter>Blur>Gaussian Blur and input 10 for both the horizontal and vertical values.

It's starting to look like a neon outline, but we need to give it some color. Click on Colors>Colorize and adjust the Hue left or right to change the color. For an added effect, Duplicate the layer, change the Mode to Addition, change the Hue just as you did before, and move the layer slightly off of the original. Rinse and repeat as many times as you want, and feel free to add some flair with the different brushes.


Draw Graffiti without Being Harassed by the Five-O

We don't condone tagging (or whatever it is kids are calling it these days), nor would we want to explain to the local cop on duty or wandering gang banger why we're leaving our mark on a perfectly good wall. Luckily for us, neither of their jurisdictions extends into the virtual world.

A prerequisite for this effect is a good graffiti font. There are a ton of free ones floating around the Web (see here), and the one we're using is called Nosegrind. You also need a good backdrop, like a brick wall. Once again, the Web proves invaluable

Open the image in GIMP that you want to tag, then select the Text Tool in the toolbox. Choose your font and desired size, then click on the image and begin typing.

Next, right-click the text layer and select Alpha to Selection, then create a new transparent layer drag it and under the text layer. Click on Select>Grow. How large you decide to grow the selection will depend on how large your image is, but we recommend starting with a value of 10 and seeing how it looks.

Now we're ready to add color to our graffiti. Pick a light and dark color for your foreground and background. Make sure the new layer you created above is highlighted, then select the Blend tool with Mode set to Normal, Gradient to FG to BG (RGB), and Shape to Linear. Draw a straight line up or down on your selected text. Click Select>None.

Right-click the top black text layer and select Alpha to Selection, then Select>Grow. Grow the selection by about 25 percent of the original value you grew it by previously (so if you grew it by 20 before, grow it by 5 this time). Make a new transparent layer and move it beneath the black text layer. Pick a different color than the one you used before and select a light (foreground ) and dark (background) shade. Select the blend tool and draw a line down over your text. Merge the layer down.

Now we need everything to blend into the brick background. Right-click on the top layer with black text and select Alpha to Selection. Change the foreground and background to a dark and light gray, respectively, and draw a line from the bottom to the top of your text with the Blend tool. Now go to Filters>Map>Bump Map. In the top pull-down menu, select your brick layer, change the depth to about 10, and hit OK.

We also need to change those gray colored bricks back to black. Go to Colors>Brightness and Contrast and decrease the brightness to about -115 and increase the contrast to around 35.

In our example, we used green and pink colored graffiti. To make these also blend in with the brick wall, go to Select>None, then right click the green text layer and select Alpha to Selection. Apply the bump map filter as you did before, only this time you don't need to follow that up with a brightness and contrast adjustment. When you're finished, click Select>None and repeat this step for the pink text layer.

Use different brushes to sprinkle in some paint splatters and other effects to make it look more realistic.

(Credit: GimpTV.net)

Additional Resources

www.ghuj.com
Gimp.org/Tutorials
Gimp-Tutorials.net
Gimp-Tutorials.com
Gimper.net
Gimpology.com
Pixel2Life.com

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