Neutral Density Filter or ND Filter
Ahmadzargon. Neutral density Filter (ND-Filter) is famous landscape filter which is used to reduce light intensity trough the censor and decrease light exposure. This characters may cause a long exposure when we capture an image. Please read also Long Exposure Photography.
A good Neutral Density Filter should not remove light characteristic such as does not give any color fill but some of ND filter gives a fill color into your photo. The color fill sometimes Soft color such as magenta, cyan and red. It depend on ND quality. I suggest to use B+W(trademark) filter. This filter does not give any change of light characteristic and color fill but you have to prepare more budget to get this one.
How to use ND Filter?
The first thing we have to know about ND filter before we use it is “How Strong ND filter Reduce Light Density”. ND filter is signed with a number of it stop. Actually there three kind of stop units of ND Filter. One of them use logarithmic series such as ND-2, ND-4, ND-8, ND-16 and ND-32. The others units use high number such as ND-400 and ND-1000 or ND-0.6 etc. The sign depend on ND Filter trademark.
ND-2 reduces 1 stop of light exposure. It means if you capturing a photo without ND-2 Filter in 1/30 second, you have to reduce one stop if you use ND-2 filter and capturing your photo in 1/15 second. Each number increased, light stop increase one stop. ND-2 for 1 stop, ND-4 for 2 stop, ND-8 for 3 stop, ND-16 for 4 Stop, and ND-32 for 6 stop.
ND-400 and ND-1000 generally used by B+W filter trademark. ND-400 reduces light density until 8.3 stop and ND-1000 reduce almost 10 stop. Do not be worry about ND filter stop number. Manual guide always include in to your packet when you buy it. so, you just need to read it.
Frequently Question:
Question: what should I do to get a normal exposure photo?
Answer: Aperture priority mode make your camera calculating time exposure manually. In term of high number stop such as 8 until 10 exposure stop, you need to calculate it manually. DSLR Camera time shutter is limited to 30 second. It means: you have to choose bulb mode and cable shutter release to help you capturing image in 30 second or more.
read also! Tips For Long Exposure
read also! Tips For Long Exposure