We've all seen the long-exposure shots of waterfalls where the water's silky smooth, or the clouds just streak across the sky.
The technique can also help eliminate crowds from pictures, especially if they move fast enough.
The problem is, if you try to do them in daylight, you can't stop down far enough to get the really smooth effect. Even if you set your ISO as low as the camera permits and use the smallest aperture, you might be able to get a second, at most.
One way to reduce the amount of light coming in is to use a variable neutral-density filter, which allows you to dial in the amount of light-blocking you need to lengthen out the exposure.
But if you can't find one, or afford one, there are a couple alternatives. This time we'll talk about using a pair of polarizing filters to do the job.
As you know, a polarizer works by blocking light coming from particular angles. Normally, photographers use the filters to darken the sky, increase contrast or eliminate reflections.
But if you put two of them together, you wind up blocking most of the light coming into the camera. Try looking through a polarizing filter while wearing polarized sunglasses, and you'll see the effect.
To do this with a camera, you need two polarizing filters screwed together and then placed in front of the lens. By turning one of them, you can darken the image to the point where you can get a long exposure.
Here's a photo taken without the filter in place. It's about 1/25 of a second.
The technique can also help eliminate crowds from pictures, especially if they move fast enough.
The problem is, if you try to do them in daylight, you can't stop down far enough to get the really smooth effect. Even if you set your ISO as low as the camera permits and use the smallest aperture, you might be able to get a second, at most.
One way to reduce the amount of light coming in is to use a variable neutral-density filter, which allows you to dial in the amount of light-blocking you need to lengthen out the exposure.
But if you can't find one, or afford one, there are a couple alternatives. This time we'll talk about using a pair of polarizing filters to do the job.
As you know, a polarizer works by blocking light coming from particular angles. Normally, photographers use the filters to darken the sky, increase contrast or eliminate reflections.
But if you put two of them together, you wind up blocking most of the light coming into the camera. Try looking through a polarizing filter while wearing polarized sunglasses, and you'll see the effect.
To do this with a camera, you need two polarizing filters screwed together and then placed in front of the lens. By turning one of them, you can darken the image to the point where you can get a long exposure.
Here's a photo taken without the filter in place. It's about 1/25 of a second.
You can see the water in the pond doesn't look smooth, and the water cascading down the rocks has some detail in it.
Here's the same shot at 81 seconds.
Now, we have the smooth water and the streams almost look like a mist. The only drawback to this method is the blue cast from the filters. But I was able to fix that by increasing the color temperature.
You'll need to lock the focus in before you darken the filters, and it may take some guestimating on the exact exposure, but the effect works.
Next time, I'll show you a way to do it without a filter, even in broad daylight.
Next time, I'll show you a way to do it without a filter, even in broad daylight.
