Start with Good Resolution

• With digital photography, you need good resolution if you want photo quality prints sized 8 x 10 inches or higher. A 4-megapixel camera may be good for casual snapshots, but if you plan to hang prints on a wall, Consumer Reports in its online buying guide recommends a camera with at least 6 megapixels. If you're looking to produce posters, you better have an 8-megapixel camera.
  The number represents the number of pixels the camera captures in an image. More pixels means finer resolution amd sharp detail. The more information you capture in the image to begin with, the better results as you apply effects.
  
  

Select High Contrast Images

• Any effect you edit into an image will cause some loss of detail, for in essence, you're digitally painting the image with a broader stroke. Photos that may be intricate in detail, but do not have a wide range of color or a great difference between highlights and shadows, may yield poor results when you select a filter effect. Simply raising the contrast could reduce that detail into a black blob.
  Shoot images that have high contrast before editing: a face lit from the side, leaving half in shadow; backlit subjects; stark architectural details. Images that already stand out in shape and color, rather than subtle gradations, are prime subjects for special effects.
  
  

Adjust the Basics

• Moving the sliders adjust highlights, shadows and midtones in the image
  
  Before you select the filter effects gallery in Photoshop, or the equivalent in other photo editing programs, see what you get by adjusting brightness and contrast, or color saturation and hue. In Photoshop, you can adjust the exposure by a brightness/contrast menu, or you can use the levels menu for finer adjustment of highlights, midtones and shadows. Adjusting the levels, for instance can give you an until-high contrast image.
  Adjusting the hue and saturation levels can make the colors stand out brighter than they are naturally, or you can make the colors more subdued. You can also supersaturate the image to give you a false color image for dramatic effect.
  
  

Sampling Photoshop's Filter Gallery

• Selecting the Glowing Edges filter turns a tranquil roadside scene into a bizarre, nightmarish image
  
  Photoshop gives you a range of filters that greatly alter an image, sometimes in unexpected ways. Using the filter gallery lets you sample the effects quickly. You'll discover some of the effects don't work at all with the image you have, even if the same effect worked great on another photo. The gallery lets you experiment.
  But don't decide just on a click. Each effect has its own controls. Adjusting the sliders in the effects menu can greatly alter how an effect is applied. You can also add one effect on top of another, to create a unique image.
  To create the effect you want can be a process of trial and error. Just keep trying, and you may discover a result that will surprise you and amaze others.