对比于fangcr，俺这就是小儿科了。。。

(1) Image Adjustment->black and white
(2) adjust the grey scale of each color through color channel, i.e., adjust the blue channel can turn the blue boat to black or white in the BW photo.
(3) increase contrast of the BW photo
(4) create an adjustment layer from the middle icon in the lower right corner of the PhotoShop with "Hue/Saturation"
(5) in the hue/saturation panel, adjust the Lightness all the way to right, and Saturation slider all the way to the left, now this adjustment layer looks pure white
(6) From the tool icon panel (usually in the left),select the "gradient tool"
(7) draw a vertical line in the middle of the picture,
(8) check the effect of (7), if not satisfied, undo and trial-n-error multiple times until satisfied with the fog effect.
(9) Click the icon in the lower right corner of the photoshop to add a "vector mask"
(10) Use the "Brush tool" on the left panel, adjust the size, adjust the Opacity of the brush (10%), then lightly brush on the tall tree to recover the tall tree a little bit.
(11) Crop the photo in whatever way you want (i,e., remove the unnecessary components such as the pole on the lower left corner of the photo.