Photo by Peter Bargh.
Check the weather
If you want to shoot mirror-like reflections you need to head out on a very, very still day. It isn't particularly important if it's sunny or cloudy but you do need as little wind as possible to be blowing. Watching the weather and doing your research to find lakes that are sheltered by hills etc. will help but if you do have the unfortunate luck of having several windy days in a row head to your chosen location any way and take a walk round it, checking the direction the wind is blowing from. By doing so you may find part of the lake that's still as it's sheltered when other parts aren't. Also, set your alarm clock to go off early as winds are usually lighter in a morning. Of course, for more abstract work when you need ripples, you don't need to sit at home waiting for the wind to settle down.
Use a ND Grad filter
When you check your shot on the back of your camera you may find it doesn't look quite right and that's because the reflection on the water is usually darker than what's being reflected. To fix the image so you get something more like what the eye is used to seeing, use a ND grad filter
and line it up so the darker part sits over the sky and finishes at the horizon, where the sky meets the ground. This will balance the exposure, darkening the light sky so it matches the reflection in the water. Be careful with the strength of the filter
though as if it's too strong the image will look false.
Lighten an image
By placing water in the foreground of the shot it will lighten the image which is useful when you have an interesting, bright sky and need to give the foreground of your shot some punch. If you find the sky's a little too bright, you can, as above, use a ND grad filter
to bring a little balance to the shot.
Even on still days you can get a little movement on the water's surface but you can smooth out a few ripples by using a longer shutter speed. You may need to take one with a quicker shutter speed too then combine it with the longer shutter speed shot in your editing software as if the trees, grasses etc. around the water are moving, they'll be blurry in the longer shutter speed shot.
On windy days, don't think you have to put the camera away as you can spend a few hours shooting distorted ripples and reflections. All you need to do is find something interesting (colourful too if you can) that can be reflected in the water and you'll have a collection of abstract, surreal looking shots in no time. As the wind direction can change quickly so too can the shapes the ripples form so just shoot lots and worry about editing them down once you're back home in front of your computer.
If you don't live close to a lake just wait for it to rain and head out once it's stopped falling to photograph the reflections you find in the puddles dotted around the streets. In fact you don't need a puddle, as a damp pavement, in the evening will reflect neon lights and signs. If you're focusing on a puddle make sure it fills the frame or try using a slightly larger aperture on a wider shot to throw the pavement surrounding the puddle out of focus.
Glass and other reflective man-made objects
Many modern surfaces such as steel and glass are great surfaces to shoot reflections off. You may need to boost the contrast of the shoot slightly in your editing software though as the reflection is often darker than the subject that's being reflected.
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