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<h3><img alt="" src="../sun.png" align="middle" > Binning</h3>
<blockquote>
<p>To create an image from a FITS Bin Table, the user needs to specify a binning factor, binning buffer size, and the binning function.<br></p>
<p>The Binning (or Block) Factor is defined as the following: A value greater or equal to zero. This value indicates the number of pixel values that will fall into a particular bin.<br></p>
<p>The Bin Buffer Size is overall size of the image generated. This has no relation to min and max values of the columns used to create the image.<br></p>
<p>The Bin Function is defined as the following: Average - all pixel values that fall into one pixel bin are averaged. Sum - all pixel values that fall into one pixel bin are summed.<br></p>
<p>Bin to Fit Frame will calculate a bin block factor as a power of 2 that will allow the entire data space to be displayed in the current frame.</p>
<p>By default, DS9 will bin about the center of the image. To determine the center of the image, DS9 will look for the following keywords in order:</p>
<blockquote><tt>TDMIN/TDMAX<br>
TLMIN/TLMAX<br>
TALEN<br>
AXLEN</tt></blockquote>
<p>If no valid keywords are found, DS9 will define the center as the middle of the possible data space based on the coordinate data type.</p>
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