Long Exposure shots by Tim Hall

Thank you so much everyone, I love this group !!

Shoot at dawn or dusk or a cloudy day, I always use a polarized filter it does better with preserving color and not adding a blue cast to the water. You definitely want a sturdy tripod, wide angle lens and wireless remote. The lowest ISO you can get helps as well and F stop of f/16-f/22

Scott pretty much nailed it,
That being said, I know NOTHING about long exposure other than what I have learned experimenting myself... and Scott covered that and then some. :) Good luck! Let me know what you come up with!

Great question.

First and most important thing is a tripod. It doesn't have to be a $300 ball-head, just strong enough to hold your camera perfectly still.

Second most important thing, is either using a timer or a remote shutter release. Any movement of the camera ruins long exposures.

If possible, go wireless shutter release. Under $20 on Amazon in the US for most cameras.

Third - mirror lock - you want your mirror locked, instead of the typical state where the mirror is passing light through to the viewfinder. The movement inside the camera can cause more shaking and vibrations than you think when that mirror slaps up and down. In most cases, "Live View" will lock the mirror up, so I almost always opt for Live View when shooting LE's. Otherwise look for a mirror lock setting in the menu's. A "silent" shooting mode like my 5DMkIII has is somewhere between mirror lock and no mirror lock.

Stop down that aperture. You want long exposures, so don't bother shooting at f/4 or even f/7.1. Jump up to your lens's sweet spot for sharpness, which is usually f/11 to f/16. If you need make your exposure longer without overexposing, you can go higher, f/18 or f/22, but you'll start to lose quality in that range and higher.

Lastly - experiment with exposure. Go to M mode, set your aperture where you want it, then play with shutter. Drop your ISO to 100 if there's any light - and if there's too much to get more than a second or so, you might need to look at ND (neutral density) filters to drop the amount of light coming in. A polarizer will give you a half stop or more less light too.

Be patient, take your time, and take lots of shots with different settings.

Some waterfalls look great with a couple seconds. Some less than a second if the water is moving super fast. For smaller, slower moving water, you can go much longer, 4, 6 or 8 seconds to smooth out the water. It's all about what kind of smoothing effect you want, but also how fast the water is moving.