predicting shutter speeds to freeze the action without over doing it.

[fasteddiehawaii]

Is there a way to predict shutter speeds at a set aperture of a car going 300 miles left to right at a race track without over-setting the shutter speeds and ending up at highest ISO or a maximum aperture.  Its like is there a formula that you can calculate shutter speed without going to low and blurring the motion.  camera is on a monopod and we are panning. Is this same setting good for day or night shots, too?  thanks in advance.

[Skirball]

There are no formulae that would be of practical use.  It will matter how fast the object is moving, how far you are from it, camera sensor size, and the focal length you use.  If you pan the camera it gets even more complicated.  Too much for practical use – though I suppose a phone app could do it.  But then you have to add in artistic considerations – do you really want to freeze everything?  Shooting a car race with 1/8000 shutter speed will make it look like the cars are parked on the race track.  I usually want to at least see motion in the wheels, or better yet pan the camera so that the background is blurred.

As far as shutter speed: Most people just learn some rules of thumb based on experience (posing person, moving person, athlete, moving bike, car race/plane, etc) then estimate the numbers based on their situation (i.e. if they’re using a longer lens they know they need to increase the speed a bit).  The great thing about digital photography, you can just have a look and adjust as necessary.