If you're going to attempt this Quark effect to an image for monitor display only or for use on the internet, go ahead. But if your design is used in a Quark document destined for printing (ink on paper), then using Quark's built-in contrast controls are NEVER recommended and you should find another method of creating the illusion of transparent text. This is practical advice from a service bureau professional who knows from experience that any "tweaking" of images using Quark's built-in controls can sometimes get you very unexpected results. At the very least, you should warn your service bureau that you have modified the image in this way, and definitely request a high-resolution proof (MatchPrint, color key or blueline) before going to press.
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