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			<title>Macintosh: Startup Screen Color Shifts Caused by CLUT Matching</title><body class="ac-gn-current-support">
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<h1 id="main-title">Macintosh: Startup Screen Color Shifts Caused by CLUT Matching</h1>
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<div id="intro-container"><div class="truncate"><div class="attr SYMPTOMS"><div class="attr TOPIC"><FONT SIZE=4><BR>
<BR>
When the startup screen on my Macintosh appears, it is first dark and then<BR>
seems to lighten in tone.  Why is this happening?<BR>
<BR>
</FONT></div></div> <!--  attr Symptom  --></div> <!--  truncate --></div> <!--  intro-container --><div class="clear"> </div>
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  <div class="attr SUMMARY">
The changes to the display of your startup screen are caused by the color<BR>
look-up table (CLUT).  The Macintosh has many color combinations available.<BR>
For example, on an 8-bit system, there is a choice of 256 colors out of 16<BR>
million possibilities.  The computer stores a color look-up table for a<BR>
startup screen graphic, and what you're noticing is the time it takes the<BR>
Macintosh to match the graphic to the CLUT.  During this matching, there is<BR>
also a shift in the intensity of colors displayed in the graphic.<BR>
<BR>
<BR></div>
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<div class="mod-date">Published Date: Feb 18, 2012</div>
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