The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2 QOS 
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Fig. 1 scatter-plot result 
Figure 7. Non-linearity in Butting zone 
The butting zone has the difference in grey level, contrast, 
clearness, discontinuity, etc. between each CCDs, and strong 
non-linear CCD response (Figure 7). To reduce the butting zone 
issues, the relation, the scatter plot between PAN2 / PAN4 and 
PAN3 / PAN5 has been searched for all grey level possibly 
with so many KOMPSAT-2 image data (Figure 7 right). In 
Figure 7, if KOMPSAT-2 MSC be perfect system, it should be 
red line, but we got the blue line of the non-linearity depended 
upon the grey level., The right image in figure 8 is corrected by 
the result of the scatter plot between PAN2 and PAN4, but there 
is still remnant in butting zone. 
PAN2 PAN4 
Figure 10. The principle of Dispersion method 
In Figure 11, the left image is only corrected with LF NUC + 
Scatter Plot, the middle image is corrected with LF NUC + 
BSM + Scatter Plot, and the right image is corrected with LF 
NUC + BSM + Scatter Plot + Dispersion method. The right 
image can be clearer than the left and the middle. If LF NUC + 
BSM + Scatter Plot + Dispersion method can be applied to the 
KOMPSAT-2 image data, there are no more butting zone issues. 
Figure 8. Up: Raw image data, Bottom: corrected by the scatter 
plot 
To remove the butting zone issues in all case of the 
KOMPSAT-2 image data, two more algorithm has been 
developed; BSM (Butting zone Smoothing Method) and 
Dispersion method. To fully remove the butting issues, do the 
next sequence; LF NUC —*■ BSM -*■ Scatter Plot -» Dispersion. 
In figure 9, the principle of BSM is the smoothing of the middle 
DN value of all lines at the butting zone. The weak point of the 
BSM is the case of the right of Figure 9. 
PAN 2 
PAN4 
After LF NUC 
* Mean value 
Figure 9. The principle of BSM 
LF NUOScatterPlot LF NUC+BSM+ LF NUC+BSM-r 
ScatterPlot ScatterPlot+Dispersion 
Figure 11. The result of BSM + Scatter Plot + Dispersion 
method in butting zone 
3. MTF AND MTFC 
3.1 MTF Value 
Lines/m 
Figure 12. The beginning MTF value of the KOMPSAT-2 with 
Siemens target at Stennis Space Center in USA