Dear Fellow remote sensors, Running ENVI 4.3 on WinXP service pack 2 I am currently trying to fuse a RadarSAT-1 image (res 6.25m) to an ASTER MX (res 15m) data set. Essentailly the SAR image is acting like a pseudo panchromatic band where it is used to inject texture and improve the spatial resolution of the ASTER data. I have used the brovey and HSV approaches with no problems, however, when I attempt to use the PC sharpening approach I run into problems. Following the completion of the module the resulting imagery looks okay but when I look at the individual bands it is clear that there are problems with the fusion. Basically, SAR texture has been added to the NIR band but the green and red bands have merely been replaced with the SAR image resulting in severe spectral distortion. I would like to know if anyone else has had this problem, I have repeated the exercise using the resolution merge application in ERDAS with similar results. The literature indicates that PCA is a fairly good fusion procedure and this is unexpected. Does anyone have any suggestions? (both images are integer 0 - 255) Regards, Wesley