At the back of my mind (from some 25 years ago) I recall blurry water 1/4 second. But as you say it all depends on the rate of flow, and the amount of blur required. Go back a month later and the flow rate will have changed, the light and mood will be different and a different length of time will be optimal for the moment. So you bracket on length of time, you're not going to set up camera and tripod dial in 1/13 second press the shutter and pack up.
I don't know, perhaps there are novices that look at EXIF data to use as a starting point, but I suspect they're more likely to have got a book on photographic technique out of the library, which has told them: blurry water long shutter speed.
I suspect they are also more likely to read "landscape photography: set white-balance to cloudy" than to ascertain that from EXIF data.
|