Editor's note -- One of the fun things about running the Inside Aperture site is receiving reader contributions. Every now and then a clever new technique shows up in our Aperture mailbox, many of which I try. But why should I get to have all the fun? So, this week I'm sharing a handful of reader-submitted techniques. My guess is that you'll find one or two particularly useful.

Removing Selective Color

by Gary O'Kane

Another reject from iStock. My quad bike image didn't made the grade. But I must admit, the guys at iStock are respectively sharp-eyed. The shot failed on two points. The logo on the back of the bike and the chromatic aberration -- the purple fringing on the chrome shock.

The shot was captured in the private grounds of Skibo Castle, Inverness, Scotland. The lens was an EF 85mm (f1.8) the shot was at f-2.2 to minimize my D.O.F.

The logo was easily removed. With Aperture 2.1, a trip to Photoshop was avoided by using the Repair/Retouch tool. The purple fringing, due a lack of not stopping down and bright highlight, was a different matter. For this I used the Color option from the adjustment HUD. Instead of enhancing and pumping more color into the image (as is often the case with controls in the Color brick), I decided to remove color instead. By desaturating the purple, I was able to remove the severity of the fringing. Of course, I observed the entire image to make sure that there was no unnecessary alteration to the rest of the composition.

Motorcycle Before Image
Here's the "before" image showing the purple fringing.
Color brick adjust
Now, just a quick adjustment in the Color brick.
After image
And finally, the "after" image showing the desaturated purple fringing.

I've been an Aperture user since December '05. Aperture has improved my game and has made me a more proficient photographer. My work covers wedding, portrait, creative, and corporate. I also teach Digital Photography and Photoshop for the local college. Originally from Ireland, I'm now based in Manchester, England.

Use Aperture Watermark to Make Baseball Cards

by Jim Westveer

I was asked to photograph a T-Ball game for my grandson last week, and I showed up with a couple of lenses and no real idea of what I was in for.

First, I should say that, if you've never attended a T-Ball game, you've missed out on a bunch of good belly-laughs while watching five year olds trying to remember all the "rules" (like run to first base after you hit the ball, not to third base).

Tball Photo
Watching kids play T-Ball was as fun as photographing them.

When I returned home, I was pleased that I actually did capture a bunch of good shots of everyone at bat, and a few of them in the field. I then thought that it might be a good idea to turn the photos into baseball cards for each of the players. A quick search with Google turned up a Creative Commons Public Domain License Baseball card template by Creative Creature.

The template is available in .psd format, and after a few minutes of adjusting/changing/ customizing, I had a template that I could use for the photos I took that afternoon. The .psd template has a background layer that you can simply use in Photoshop or gimp, replace the background with your photo, and presto/chango one has a rookie baseball card. Well that wasn't too hard, but now I was looking at exporting 25 photos, importing them into my graphics program in the correct layer, saving them to disk, and re-importing them into Aperture.

Blah! I hate mindless repetitive work. There must be some easier way.

Baseball Card Template
My baseball card template

After a bit of thinking, I came up with the idea of just saving the template as a PNG to preserve transparency, and using that image as my cookie cutter watermark to simply lay over the top of all of the images.

The only "trick" to this approach, is to save the .png template with the background set to transparency, and save it the same physical size as my original photograph. This way the Watermark fits nicely over the entire image, and the photograph is only minimally cropped by the border.

I set my export settings to use a watermark. I didn't scale the watermark, as I have already saved it the same size as your camera originals. Then, I exported the photos using my saved watermark. The rest is easy: print and I'm done.

Baseball Card
And the finished product: a cool looking baseball card.

Here's what it looks like when exported with the watermark over the photograph. And the bottom line: making 25 photo baseball cards with Aperture is a snap.

Aperture Levels Adjustment Layer

by Jordan Nielsen

There are a lot of powerful image adjustment tools in Aperture, but one of the most over-looked is Levels. It's an extremely versatile control that can turn a flat image into a wonderfully contrasted image, and it can also be used with the monochrome tool to create punchy black and white images.

There are many different aspects to the levels adjustment. You can control the luminance levels in an image (blacks, whites, quarter tones, three-quarter tones, and midtones), as well as change the red, green and blue tones in the image with the black, white, quarter tone, three-quarter tone, and midtone sliders. If this sounds interesting to you, I'd like to take you on a brief tour.

Luminance Channel: Color Images

Baseball Card
Luminance adjustment in Levels

First, let's look at a color image and see how we can use the levels adjustment. When I work with this adjustment for an image, I often start in the luminance channel. Lots of people might use the contrast adjustment to create a stronger image, but contrast not only changes the punch of an image, it also changes color values. That is why using levels adjustment in the luminance channel is better, changing only the luminance levels of the image rather than the color values.

Luminance Channel: Monochrome Images

Just like with color images, the luminance channel can work wonderfully for monochrome images as well. Lots of people enjoy looking at high-contrasted black and white images, and using the luminance channel to produce this effect is a great option. (However, using it along with the red, green and blue channels is even better, as I'll describe in a minute.)

RGB Channel: Color Images

Baseball Card
RGB adjustment in Levels

Yes, I know we now have the advanced Color brick in Aperture. But you might be interested to read that you can also use the red, green and blue channels in levels to desaturate or saturate. Just drag the black point slider to the right to desaturate the channel or the white point slider to the left to saturate the channel in the image. Interesting, huh?

RGB Channel: Monochrome Images

Using the RGB Channels along with the monochrome mixer can create much more dynamic black and white images in Aperture than just using the luminance channel. In the Monochrome Mixer, for example, you can adjust the mix using the red, green and blue sliders. You can make similar changes using those controls in Levels too. Play with the red, green and blue channels in the levels adjustment to see how you can further alter the look of your black and white images.

Even though this was just a quick overview of the Levels adjustment, it should get your creative juices flowing. If you have questions or comments, please post a comment at the end of this article.

And That's a Wrap (for now)

Feel free to add your ideas to these tips by placing a comment. And if you have a new tip all-together, then send it to us. See you next time!