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Дата изменения: Unknown Дата индексирования: Mon Oct 1 23:12:41 2012 Кодировка: Поисковые слова: ngc 5128 |
The threshold and saturation values are not automatically set well for most x-ray data files since the software samples a few pixels only and x-ray data has few photons. It is possible to set them by hand for an individual image:
tv> display ``xdata$rp110590.qp[block=30]'' 1 zscale- zrange- z1=0 z2=30
This turns off the default mapping of intensity to color (zscale-) and sets 0 counts/pixel at color-scale minimum and 30 counts/pixel at color-scale maximum.
or try
tv> display ``xdata$rp110590.qp [block=30]'' 1 ztrans= ``none''
This sets the z value = the number of counts in each pixel.
Another technique is to use the task xdisplay which is identical to display except that z1 and z2 are scaled appropriately for an x-ray image.
xr> xplot # load the relevant package xp> xdisplay ``xdata$rp110590.qp[block=30]''