Some constructive criticism INCOMIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIING:
http://farm7.static.flickr.com/6019/6319859235_af5e1edddc_b.jpg
http://farm7.static.flickr.com/6043/6320380442_5999d9fa69_b.jpg
http://farm7.static.flickr.com/6056/6319857413_13da3d738f_b.jpg
In these, the massive yellow reflection on the side draws a lot of attention and kind of "ruin" the shots, as they would be very nice without it. The composition is great in the last two, nice colouring etc. So they're all good except for that damn reflection. Invest in a good polarizing filter and Bob's your uncle.
http://farm7.static.flickr.com/6227/6319854065_767cbe6a24_b.jpg
Good shot here, only thing that springs to mind is that window reflection.
http://farm7.static.flickr.com/6117/6319860865_3bd90580ba_b.jpg
Should have moved the cars further to the right to make the background "one" instead of the disturbing break in the background on the left side.
http://farm7.static.flickr.com/6037/6320384274_665bb84c13_b.jpg
Same goes for this, only that the car should've been moved left to avoid the disturbing parts. If you end up having only the sign in the frame, try cloning it out.
http://farm7.static.flickr.com/6057/6320386088_171e4c2cd5_b.jpg
I like this one, only thing to point out is the boot handle. Maybe crop it or twist the camera a little to remove it from the frame.
http://farm7.static.flickr.com/6105/6320386780_69a616a543_b.jpg
Try to remember to always align the car towards the sun so that you light the part of the photo you are trying to enhance. A few disturbing elements in the background here too, but seeing as it's a street shoot its not much you can do about it, except maybe shoot in bracket mode and blend in the car in a darker background to make the car itself stand out.
http://farm7.static.flickr.com/6215/6320388838_dc7905955d_b.jpg
Same thing about the lighting here, maybe you could also clone out the car in the far back and the sign on the wall to clean up a bit.
http://farm7.static.flickr.com/6222/6319863781_81b4388794_b.jpg
Good shot, this is the ideal background situation as I've mentioned further up. The only thing to point out is the damn reflection in the windows again. Get a polarizing filter and it'll be great.
http://farm7.static.flickr.com/6040/6320389614_348ec32c86_b.jpg
Good shot, but again the background is a bit disturbing - although I'm being very picky. The "work containers" on the left doesn't flow with the rest of the pic, and you should've picked a background that was more symmetrical (i.e. graffiti on the left side too, or the same "containers" on the right side.)
http://farm7.static.flickr.com/6235/6319861437_75bec04141_b.jpg
See of the Lupo from the same angle for what you should do, but also it should only be that one car in the frame, as the other one doesn't "give the picture any more meaning" if you understand where I'm going at.
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Don't be offended or anything about what I've written, just some pointers to make you a better shooter
