I Was Reading A Post Yesterday That Spoke Of A Len' Sweet Spot. I Feel Like Im Constantly Trying To Squeeze Every Bit Of Available Light I Can Get Just To Make A Shot, Hence Im Always Shooting All The Way Open And Still Getting Under Exposed Shot That I Feel I Need To Lighten In Photo Editiing Software. I Dont Like The Grainy Look I Get When I Use Iso 800 But What's My Alternative. I Use A 20d With The 17-85. It's Like I Shoot Shoot Shoot And Once In A While I Get A Good Shot. But I Really Feel Lost Most Of The Time.