mcrow5 wrote in post #16020003
MassiveSi wrote in post #16016281those are pretty slow speeds, what is likely to be sharp at 1/30 ?
you can get the whole car in focus, but you wont get it all the time. im comfortable doing shots at 1/60. its all practise, practise and practise some more! if you cant get speeds that slow, find one you can get sharp shots at 50% of the time. and practise on that speed, and make your shutter speed slower as you get better.
MassiveSi wrote in post #16020094the OP specifically said he was having difficulty getting sharp images, I just didnt think going to 1/30 will help him in this instance
I have to agree with MassiveSi here, that using slower shutter speeds isn't going to help the OP get sharp shots, if they aren't sharp now at 1/160th plus.
Yes, slow shutter speeds are best for motorsport, but what is "slow" depends on a number of factors, the decision as to which speed to set needs to allow for focal length, distance from the subject and their angle of approach. A car driving in a precise arc around the photographer, staying at the same distance the whole time, can be shot at a much slower shutter speed than one approaching along a straight and being shot as it approaches quite close to the photographer. Panning the first scenario at 1/30th should (skill permitting) give a result with the car sharp from end to end. The second scenario would result in a sharp image at the point you are tracking on, but the ends of the car (if tracking on the driver) would be blurred as they are moving at a different relative speed to the camera pan. That can be used to good effect for artistic results of course.
It is easy to say "shoot at 1/30th or 1/60th", but without describing the parameters of the scene it is not necessarily right. A car passing some distance away, at 70 mph as it comes around a corner that you are on the inside of, can be fine at that speed. One passing 15 metres away, on a straight, at 180mph won't. You can shoot the latter at 1/200th and still get plenty of background blur, due to the much greater angle of rotation as you pan.
I shoot motorsports, mostly at 300 or 400mm, and use shutterspeeds between 1/30 and about 1/160th usually, depending on the angle and speed of the cars or bikes.
mcrow5 does make a good point about practicing at a relatively "safe" shutter speed, and gradually bringing it down as you get better. Personally, I deliberately aim for a fairly low keeper rate. I work on the principal that if I am getting a fairly high proportion of sharp shots, then I am not "pushing the envelope" enough. I prefer to have a few shots with great blur than hundreds with good blur. I am happy to have to delete hundreds of shots that vary from slightly soft to very obvious camera shake, where the pan was less than great, so long as there are some sharp shots too. I can shoot each car / bike several times during the day, I only care about getting one really nice shot of it.
Going back to the OPs problem, the 7D has a much more complex AF system than you are used to, it needs to be set up more for specific situations to get the best from it, and if you have it set up totally wrong for what you are shooting it could even make things worse than the basic "Jack of all trades, master of none" system on your old camera. I haven't used a 7D, so can't comment specifically on fine tuning the AF for motorsports, but a couple of other posters above seem to have dealt with that.
Yes, also practice your panning technique, keep your focus point on one specific part of the car (the driver for example) in order to be sure that you are keeping your pan dead on, if your AF point is wandering, then you will see blur from camera shake at slower speeds. Remember to start tracking the car from some distance before you want to shoot, in order for the AI servo to get a good idea of speed and so be more accurate with it's adjustments, and follow through with the pan for a moment or two after you take your finger off the shutter button.
