Are you addicted to long exposure shots? don't limit yourself only to night time. This guide will show you what you need to take those blurry motion pictures even on bright day.
You’ve all been reading lately tipsters about how to take long exposure pictures at night, how about taking this knowledge a step further? let me introduce you to ND filters.
ND (Neutral Density) filter reduces the light entering the lens, and requires use of longer shutter speeds or larger aperture to obtain same exposure, there are different strength of ND filters available from ND2 (0.3) up to ND1024 (3.0) which means ND2 reduces 50% of light coming trough lens while 3.0 only allows 0.098% of available light trough lens, If you are shooting at 1/250 of second, this is reduced to 1/125 with ND2 filter and 4 seconds with ND1024 filter so you will have to choose correct ND filter for your needs, if you want water falls to look like milk and blurry sky clouds go for strong filters like 3.0 but if you only want to use large aperture on bright day than 0.3 and 0.6 should do great work.
If your camera has filter screw mount you’re lucky, you can get screw-in filter or holder and get square filters like show on picture above. I’m using Lee Holder Adapter with HiTech ND 3.0 filter for easy put on and off, don’t expect the camera light meter to work correctly with 10-stop filter (ND 3.0) you have to as well compose the scene before putting filter on because you cant see trough it so the work flow looks something like that
- manually focus
- Take meter reading
- put filter on
list below should give you idea of how much ND 3.0 filters reduces the light:
Camera reading without filter / shutter speed need for correct exposure with 10 stop filter:
1/500 / 2secs
1/250 / 4secs
1/125 / 8secs
1/60 / 16secs
1/30 / 32secs
1/8 / 2mins
1/4 / 4mins
1/2 / 8mins
1 / 16mins
2 / 32min
There’s also iPhone and iPad application called NDCalc. This will do the calculations for you and provide you with a count-down timer
Of course you will need the basic stuff like remote shutter release and good tripod as well if you want steady shots