how do i take pictures of cars like this?

DoP? I think you mean DOF or Depth Of Field. That is achieved by using a low f/ for the situation. I think you are meaning like the image in the middle of the wheel shots? He used f/2.8 for that shot which would give him a shallow/short depth of field. His focal point was about 2meters from the lens. The closer you are to your subject the shorter your depth of field will be and the lower your aperture the shorter your DOF will be. He is also using a pretty outstanding lens that will produce some nice sharp results. There is not any special lighting used and his camera indicated that no flash was fired at all.
that particular shot was taken with a Canon T2i with a 17-55 f/2.8 lens on it. the shooter was in aperture priority mode and shot at f/2.8, shutter of 1/500 and ISO 100. He or she used an exposure compensation of -2/3 of a stop and shot in raw. What does that mean and why did he make those decisions?

The aperture priority was decided to keep his depth of field shallow or short. He knew he had more than ample light to get proper exposure and the most important thing in that particular photo was blurring what was not his main focus-so he chose the aperture to be his priority. The ISO-again he had ample light, so he knew he didn't need to bump up ISO to keep a safe shutter speed.
He/she also used a custom white balance so that he didn't have to mess with color casts later.


HOWEVER it was then edited and that is where he got much of his "Look." That and many of his choices in exposure and WB weren't so great. Especially the -2/3 exposure compensation because he raised the exposure 1.25 stops and changed the white balance to 6750 and the tint to +2.
Here is where he got his "look:" He shot it in raw and in Adobe camera raw he did the following:
Color temperature 6750
Tint +2
Exposure +1.25
blacks +5 (this will add contrast and will also saturate your colors a bit more when they are faint)
Brightness +50
Contrast +58
Boosted the vibrance +15
Clarity -2 (I have no idea why)

He used the medium parametric curve split and didn't use the curve at all as well as his sharpening being the camera raw defualt-which suggests to me he doesn't know how to finish an image in adobe camera raw/lightroom. He edited in CS4 and his colorspace is Adobe RGB which means what he is seeing and what the world is seeing on the internet is not the same. There was then some work done in photoshop which I cannot read from the exif data.

In short? It's fairly heavily fixed in post processing. He made sure he had good lighting for the vehicle, a good, un-cluttered and simple background to shoot in front of and paid attention to the light and dark on his subject. He then fixed what wasn't quite perfect using Adobe Camera Raw and Photoshop CS4 to get the contrasty look he has there.

Does that help you some?

ETA- I am browsing through some of the shots you have. Step away from the tinted editing and the fake vignette. You have the right idea. Be COMPLETELY aware of the background and what may distract your viewer from the vehicle-or may merge with it and not look right.
the convertible in the garage was a good thought, edit out the exit sign, stairs sign and the sign on the post to the camera right. Those things are drawing from your basic good image. Pay attention to the lines of the lights and the ceiling in that one. Had you moved so that the exit sign was behind the roof of the car the lines in the lights and ceiling would have been amazing leading lines leading right to the car. You were shooting a very symmetrical shot there, however the parking garage isn't symmetrical. You have one brick wall to the right, but a cement pillar to the left. Copy the brick wall and create one to the left or copy the blackness and cement pillar and create it to match to the right.
Paying close attention to those details would have made that shot.
The caution tape on the line of cars-edit it out. Details details details. It's all in the details.
Your blacks are so black in that one that the wheels have lost detail. I know from being a car dealer all my life and having race cars that rims are one of the BIG details of a vehicle.
The pink toned one of the black Kia. Remove that license plate. Very detracting. And the pink tinge. Not a bad shot!

I second steve's recommendation on the 50mm. You will get much sharper details with it also!

Depth of field (I assume that's what you mean by DOP) is affect by two main factors:

Camera to subject distance-The closer the camera is to the subject, the shallower the depth of field.

Aperture-The larger (smaller number) the aperture, the shallower the depth of field.

Focal length affects it to a degree, but only tiny amounts that are relatively insignificant.

Below are the settings used in the first photo.

Camera Maker: Canon
Camera Model: Canon EOS REBEL T2i
Lens: EF-S17-55mm f/2.8 IS USM
Image Date: 2011-09-04 20:49:38 -0700
Focal Length: 17.0mm
Focus Distance: 1.72m
Aperture: f/2.8
Exposure Time: 0.0008 s (1/1250)
ISO equiv: 100
Exposure Bias: -1.33 EV
Metering Mode: Matrix
Exposure: aperture priority (semi-auto)
White Balance: Manual
Flash Fired: No (enforced)
Orientation: Normal
Color Space: Adobe RGB (1998)
GPS Coordinate: undefined, undefined
Software: Adobe Photoshop CS4 Windows

Ok, first of all, your photos cannot be viewed on FB. Second, I don't really see such astounding shallow DOF on the Miata photos. But to speak generally about obtaining shallow DOF, your lenses are not helping you one bit. They are too wide angle, and your apertures are too small.

There are a few things that contribute to shallow DOF. One is focal length. All things being equal, an 85mm lens will have much less DOF than a 24mm lens. Another factor is aperture. The larger the aperture, (smaller fstop number), the less DOF. You need to be working with a lens with at least an aperture of 2.8. Something in the range of 1.8 or 1.4 would be even better. Your lenses are fighting you at every turn. When you zoom into a more telephoto focal length, your aperture closes down on you. Result, a deeper DOF. If you stay at the wide angle focal length, your aperture is marginally better, but the wide angle makes a shallow DOF almost impossible.

Here is the lens I suggest you get and use if you want a shallow DOF. The 50mm 1.4. There is also a 50mm 1.8 which is FAR less expensive if that is a concern, but the 1.4 is the better lens. At any rate, with the crop sensor on your camera, the 50mm lens will give an effective field of view as an 80mm lens. Work at the larger aperture. I suggest you stop the lens down a couple of stops for the sharpest photo. So with the 50mm 1.4 lens, you could shoot at 2.0. With the 50mm 1.8 lens, you could shoot at 2.8. Be aware, you will have to be further away from the vehicle, but you WILL have a shallow depth of field. You should also manually focus as focus is critical when using such large apertures. If you ever want more of the car in focus, simply select a smaller aperture, such as f8.

SLR cameras have the ability to change lenses for a reason. You just have to understand when and why you need a certain lens.

steve

PS... the negative camber on that Miata is horrid. The tires will wear on the inside tremendously and handling will be very compromised.

see how your maximum apertures for all of your lenses are like 3.5.....welll they might be shooting with a 1.4 or something...also no doubt they are using pro lighting, and they understand how to pose a car for pictures...even still, i didn't see anything overly spectacular they were doing.