Curves for Photoshop Elements 4 and Above
The free Earthbound Light Curves solution for Photoshop Elements works great up through Elements version 3, but Adobe decided to change things in the newer versions. I've been looking for an affordable Curves solution that works in Elements 4 and above for some time now and I know many of you have been too since I've read your emails. Of the options I've looked at, the one that stands out from all the others is easy.Filter SmartCurve by Alois Zingl in Vienna, Austria. It's free, and it works in Elements versions 1 through 6.
Installing SmartCurve is easy. Just download it and unzip the file to reconstruct the folder hidden inside. Drag the folder into your Photoshop Plug-ins folder and restart Elements. This will usually be located at "C:\Program Files\Adobe\Photoshop Elements 5.0\Plug-Ins," or a similarly named folder if you are running an earlier version of Elements or installed Elements on a drive other than C:. Once installed, you can restart Elements and you will be good to go.
Open your favorite image and you will find SmartCurve under easy.Filter on the Filter menu. Select it, and the SmartCurve dialog will open. There you will find a preview thumbnail of the image you are working on together with a lot of great features. Let's look at a few.
Next to the preview image you will see the standard default "non curve" diagonal line. Click on it and drag the line around as you would Photoshop's own Curves dialog. You can adjust the curve for each individual channel if desired by selecting Red, Green or Blue from the dropdown Channel list. Checkboxes are provided to turn on highlighting of any Shadow or Highlight areas that you may be clipping. You can change the color used to highlight each by clicking on the corresponding color sample small square.
SmartCurve also provides eyedroppers for Shadow, Midtone and Highlight adjustment. To make correction of color casts easier, you can set as many Midtone points as you need by holding down the Alt key while clicking with the eyedropper. After using the eyedroppers, you can continue to adjust the curve by hand if you want to fine tune things. By default, the eyedroppers sample the color of individual pixels when clicked. If you hold down the Shift key while clicking though you will get a 3x3 averaged reading. Clicking with the Control key held down will give you a 5x5 average sample. Right-mouse clicking on an existing point will delete it, or you can use the Reset button to start completely over.
There's an autocorrection feature as well that will automatically adjust the shadow and highlight points for you. Hold down the Shift key while clicking on Auto to adjust all channels together to adjust contrast only. Without the Shift key each channel is adjusted individually. By right-mouse clicking on the Auto button you can alter the percentage of clipping of shadows and highlights that will occur. Higher values will result in more contrasty images.
Below the preview image is a histogram display which is based on whatever the preview is showing. If you have zoomed into only a portion of the image, the histogram will reflect only that portion. The histogram normally shows as what SmartCurve calls a "smart histogram," which uses a higher accuracy method to smooth out any peaks and gaps that may have resulted from the curve adjustment, a common problem when editing 8-bit images. Single-clicking with your mouse on the histogram graph will turn on grid lines over the histogram. Clicking again will switch to a normal (non "smart") histogram. Clicking one more time with your mouse will display a normal histogram with a grid, and clicking one more time will get you back the default smart histogram. You can cycle through all four views by just repeatedly clicking.
You can save and re-load curves as standard *.acv files that are compatible with Photoshop's Curves feature. If you adjust one image and save its curve this way, you can then apply it to a batch of images since Elements will list the last filter used as the first entry on the Filter menu. After manually adjusting one image, you can apply the same curve to other open images by selecting SmartCurve at the top of the Filter menu or by using the keyboard equivalent Control-F.
While you won't need them much for photographic adjustments, the SmartCurve control can be changed from being a smooth curve to one that allows for sharp turns or one that allows you to hand-draw any shape you like. Not my cup of tea, but fun for pop art experiments perhaps. You can use the Smooth button to progressively tone down the sharp corners as needed. When drawing with sharp corners, the Smooth button replaces the normal Auto button.
As an added bonus, the entire SmartCurve window can be resized as big as you want. The preview image will automatically resize with it to fit. If you have a big monitor, you will definitely appreciate the ability to have a big preview image since the main image isn't a live preview as it is for the most adjustments built into Elements. You can also zoom in or out on using the controls underneath the preview image.
Unfortunately, due to how it was written SmartCurve runs on Windows only, so you Mac OS users will have to look elsewhere for Curves. It also won't run as an adjustment layer, so once you apply the curve you are committed to it unless you resort to the Undo History palette. It does support both 8-bit and 16-bit images which is great now that Elements has improved support for 16-bit mode. If you want, it will also work with Element's big brother Photoshop CS2. Most users of the full version of Photoshop will find all they need in the built in Curves capability, but if you use both Elements and Photoshop, having the same Curves feature in each may make sense for you.
Curvemeister works too, but at $79.95, it's a bit much for many Elements users. If would be great if Mike Russell would release a Curvemeister Lite version to better satisfy this need. If the price of the full version does fit your budget though, the program has many unique features that make learning Curves easy and downright fun.
And yes, Elements 5 does have a Curves feature built-in, but it's limited to a small number of predefined curves, so I can't recommend it for much.
Update 2008-01-08 - It's worth mentioning that SmartCurve works in the new Photoshop Elements 6 as well. Good news for those upgrading.