I like the composition and panning on these. You also have some nice wheel blur too. I love the wheel off the ground, I think it adds a sense of excitement and danger. I think the cars look a little soft, compared to your previous attempts, but I think that is a function of this 28-135mm lens that you used this time as compared to the 70-200mm last time. Last time the cars were much sharper. I realize that it was a dreary day, so that can certainly have an affect on the outcome. If it's cloudy and gray I would not use the polarizing filter, because it just further darkens the photos and you loose 2 f/stops. Stick with the UV filter on days like this. You may get some glare on the windows though, but since you're shooting from the side, it may not be an issue.


I think you are doing better with your background blur too, but I would still open up the lens a couple of f/stops. Perhaps, consider a slightly faster shutter speed (note the slightly blurred numbers and letters on the red porsche) and maybe that will yield sharper images of the car, but you may just be at the limits of your lens.


Since the weather wasn't cooperating you should also consider some post processing, by trying to improve the red color of the porsche and the green grass.


I hope you find this C&C helpful.


Rich