[Canon beginner]

講質素邊支好d, thx

[ACanonGuy]

I have the 17mm and played with 20mm for a little bit. They are both very nice lenses. If cost difference is acceptable I would go with the 20mm given aperture advantage and longer focal length. Many others said 20mm has a better image quality but I didn't play with it enough to tell the different. Check out these pictures. They are from the 17mm and E-P1.

http://dcfever.com/forum/read.php?f=16&i=3107&t=3107&phorum_auth=3a5e0b915b85903e9914f7020d9b528f

[c6005408]

20mm f1.7
用過你就會知點正。
得閑去相機店討試下。