There are times when you’ll have correct exposure in only parts of your image. Others will be lighter than you want them to be.
This is where we use neutral density filters, or the graduated version (GND filters), to bring out detail in those areas.
Read on for all the information you need on how and when to use them.
What Is a Neutral Density Filter
An ND or Neutral Density filter stops light from entering the lens and hitting the sensor. These fit on the front of the lens with the help of an adapter.
Or you can buy these neutral density filters that clip on the inside of your camera body. The adapter that holds your ND filters needs a ring to fit onto your lens.
Most manufacturers provide these rings, ranging from 49 mm to 82 mm. The neutral density filter looks like a square of dark glass.
You can buy graduated ND filters, but these are for sunsets, and bring down the light from only part of the scene.
Many companies sell packages. You can buy adapters and rings, and a whole range of ND filters and graduated filters together. Your parents might even have some Cokins lying around.
The ones I use are from Rangers. They provide 4 ND filters and 4 Graduated Filters (2, 4, 8, 16), 9 Filter Adaptor Rings (49-82mm), ABS adapter. And they all come in a nice pouch.
ND filters are quantified by their optical density. Or a little simpler, their f/stop reduction. An ND16 filter will lower your f/stop by 4 stops. Instead, you can lower your shutter speed, which is more beneficial for long exposures.