Originally Posted by Lillebror
Woah dude! How do you take those pictures of cars and moving objects, where its in focus, but everything around it is blured out? Ive always wanted to learn!
The technique is easy to learn but depends on your handholding technique can be very difficult to master.
The photos shown are nice and I imagine the shutter speed is down to around 1/1xx or so to achieve the look he has. Maybe the speed is even higher than that as I don't know the available light on that day.
Anyway in order to achieve an effect like that you would be using a technique called "panning" which is simply achieving focus on whatever you want to shoot and following it with the camera.
In order to get a proper pan shot you need to decide first on what shutter speed you will use by figuring out how much speed/motion you want to portray. For something moving very fast it's easier to do because you can use a higher shutter speed. The slower the object the slower the shutter speed you'll need to use and the smoother you'll need to be panning the camera to follow that object.
For best results you will be using a small f-stop of say something like f/16 so that you will be able to use the slowest shutter speed possible without overexposing the photo.
Here is an example of a shot I snapped a long while back.....
Weather Conditions: Sunny without any cloud cover at around 1600hrs (4pm or so).
Car: Mazda RX-8 Metallic Blue in color extremely reflective
In order to get the shot I knew I'd need a very small aperature to keep the photo from overexposing, of course I'd also be using a relatively slow shutter speed because my position on the track was very close to the starting point so the car wouldn't be going hugely fast.
I decided that I'd be using 1/90s shutter speed because I was using a digital body and thus my lens was more like a 315mm lens meaning I'll need a higher shutter speed since I'm hand holding the camera. I have pretty good hand holding technique so it makes it easier holding at slower speeds (I was down to around 1/60s for a while shooting at 300-400mm) especially while standing unbraced.
I prefocused on the car well before the point I wanted to actually shoot the car at which is CRUCIAL otherwise you may never achieve focus anyway. As soon as I achieved focus I panned my body and the camera at the same speed the car was going as smoothly as possible. Making sure to keep the car in the frame where I wanted it to be once the car was in position I released the shutter and snapped a few shots (3-5 was plenty) making sure to keep following the car PAST the point I want to shoot at.
You have to remember that doing this is just like a sport or thowing a punch ALWAYS FOLLOW THROUGH! You will get much better shots and have less mistakes because you're following through. You'll also likely see things you wouldn't have seen if you just snap a single shot and put the camera down.
As for technique that's it, you're done.
If you want more motion then slow the shutter speed down even further, and make the aperature larger. In plain terms that would be say going from 1/90s @ f/16 to something slower like 1/60s @ f/24.
The above shot was at 1/90s @ f/24 at 315mm with no photoshop or editing. You don't have to worry about having a large aperature like f4 in order to get the background details to blur because you're panning and the background is stationary. If I was to do the car sitting still with the exact same settings then every little drop of that photo would be RAZOR sharp because the aperature is so small (f/24). In order to get the background to be out of focus I'd have to change the aperature to around f/5.6 using that same 315mm lens. I'd have to then change the shutter speed up to say 1/250s to get the photo exposed properly. However the motion would be perfectly still which would be very boring at this angle.
I hope this helps you understand how to perform shots like these. If you want practice then I suggest finding somewhere discrete and maybe shooting cars at a distance. If not you can also try shooting birds in flight which less people will be suspicious of. If you do shoot cars driving by make sure to be discrete but don't hide completely because then you will look 100 times more suspicious and could run into trouble.
Why not have a friend drive back and forth for you to practice?