Good quality digital photography accessories can easily make a photograph look different. After tripods and flash units, one common accessory that can completely change the look of a DSLR photo is filters. Filters can be considered as a fairly good option if you are looking to improve your photography skills. Various types of photography filters include polarizers, infrared, neutral density and UV filters. To maintain the simplicity of this post, we will focus on neutral density filters only.



A neutral density filter is nothing but a piece of dark glass. The purpose of a neutral density filter is to reduce the amount of light entering the camera lens and thus hitting the sensor. ND filters with a constant density of darkness throughout are known as constant ND filters whereas ND filters with variable density of darkness are known as variable density ND filters. The density of darkness offered by a variable ND filter can either be smooth or hard.







Let's focus on the shapes of ND filters. A neutral density filter can either be circular or square in size. Some ND filters come in a rectangular shaped glass too. Circular ND filters are also known as screw on filters as they can directly be screwed onto the lens thread. Square shaped filters do not have any thread, and therefore need a filter holding unit that gets attached to the lens. The filter glass along with light leak gasket can be pushed into the slot offered by lens holding unit. The image below shows my ND 3.0 filter from Haida. ND 3.0 means it is a 10 stop neutral density filter. If you want to know more about ND filter naming, here is my previous post about the



Let's focus on the shapes of ND filters. A neutral density filter can either be circular or square in size. Some ND filters come in a rectangular shaped glass too. Circular ND filters are also known as screw on filters as they can directly be screwed onto the lens thread. Square shaped filters do not have any thread, and therefore need a filter holding unit that gets attached to the lens. The filter glass along with light leak gasket can be pushed into the slot offered by lens holding unit. The image below shows my ND 3.0 filter from Haida. ND 3.0 means it is a 10 stop neutral density filter. If you want to know more about ND filter naming, here is my previous post about the naming nomenclature of neutral density filters