Waterfalls, streams, etc. are fun to shoot… There are numerous options to do. One is that silky affect that makes the water so soft. The trick is a slow shutter speed. No surprise there. Even a point-and-shoot and some cell phones can be adjusted, so even if you don’t have a dslr you can still make adjustments.
A tripod is a must for keeping the image from blurring. Also, a shutter remote (or cable if that’s what you need) helps. Another option is to use the timer function so that the camera is still when it takes the picture.
Now for the experimental part. The speed, aperture, and ISO options.
Speed: try 1/5 or slower, it’s ok to try out 1s, 2s, 3s, etc. But be prepared to adjust aperture too.
Aperture: the more open it is the more light goes in, so here is a chance to use those higher numbers to reduce the light to get those desired results. A f9 or f16 may work, but adjust as needed. Remember, the lower the number means more open the aperture is. The higher number results in closing the aperture more. If in doubt, set to speed priority and let the camera figure out a starting point.
ISO: try starting with 100 or 200. Remember this will give you the best quality. But that can be changed as it gets late in the day or down in a valley. Hopefully you practiced these adjustments.
Insights: Add a neutral density filter to your lens. This may help with those longer exposures. In a photo editor you can use the blur tools, but you can do a lot while shooting. Take shots at different settings so you can get what you want.
If you get a dark photo, adjust the aperture down a few stops to open it up. Also, slowing the speed will do the same thing.
With the aperture being open, like f3.5 (the low numbers), the focus point is affected. If you’re shooting a stream, you may need to pay attention to where it is focused on. You may have to refocus to get the exact image you want.
Just take your time to make adjustments as you are learning…
If you want the droplets and water to freeze in midair then think fast speed. This means a faster speed and lower f-stop.
Related Project Ideas for slow speed or long exposure: Photograph Lights at night- that can be train crossing arms, airplanes, cars, trains, boats, glow sticks, flashlights, northern lights, stars, carnival rides, etc. Photograph moving water like waves, you may need several neutral-density filters depending on the time of day. The ideas are limitless.