Nano IR Neutral Density ND 4 Filter (0.6) 2 Stops for Camera

ND filter is the abbreviation for neutral density filter It is a filter that reduces or modifies the intensity of all wavelengths or color of light equally. The function of this filter is to reduce the visible light at equal proportion but it won't change the brightness and color contrast of the scene.
ND filters prevent overexposure (blown-out highlights) when taking photos with a slower shutter speed in a bright place to enable a fantastic expression of waterfalls and streams. Our ND filters control the amount of light without interfering with the colors of the subject and is available in various levels to allow the selection of filters suitable for the shooting conditions or desirable finish.
Function of ND filters
1. Using ND filters in bright light environment it can enhance the subject and blur out the background through enlarging the aperture and reducing the depth of field.
2. Low shutter speed photography: ND filters can help to express the motion of moving objects through a long exposure time (e.g. to make the flowing water looks smooth and to show the trace of clouds).
3. ND filters help to eliminate moving objects in a scene (e.g. to make the crowded street looks lonesome).
4. The exposure time will be extended.
From the outward appearance ND filters are grey or black. The darker they are the more light can be reduced. Rollei Filters have a anti-reflective coating on the inside surface to reduce stray light and glare. Thanks to the harden waterproof coating the filter is scratch-resistant and easy to clean.
ND Filter's Specification
Optical Density F-stop Reduction Transmittance %
ND8 0.9 3 Stops 12.5%
ND64 1.8 6 Stops 1.56%
ND1000 3.0 10 Stops 0.1 %
ND2000 3.3 11 Stops 0.05%
ND4000 3.6 12 Stops 0.025 %
Example calculation: Shutter speed 1 second without Filter -> With ND1000 filter shutter speed = 17 minutes/4 seconds
 
1. For our ND filters high quality optical glass is selected. Both sides have a precision polishing to ensure low color shift and high definition. The color of ND filters made  of resin material can easily fade and there will be color shift. Moreover ND filters out of resin material cannot reach HD standard. Our ND filters are multi-layer coated on both sides to avoid corrosion.
2. The Nano AR coating will reduce glaring. Amazing oil repellent performance allows easy wiping, which makes daily maintenance easier. Smudge on the surface of the glass adhered during photo shooting can be wiped off easily. Static contact angle of ND coating Multiple layers of nano-coating technology are applied to glass surfaces.
Like all our photography filters, PFPE nano-coatings are applied to the optical surfaces of the filters to repel water, oil, dust, and dirt.
 
Perfluoropolyethers (PFPE) are used as hydrophobic and oleophobic coating agent. The end result is that water droplets on the surface of the filter can maintain a static contact angle of 110 degrees. Untreated glass can barely maintain 15 degrees. Even a well-known brand's 10 stop filter keeps less than 40 degrees and their 6 and 15 stop filters do not even have water repel coating.
 
3. IR ND filters are made of colorless optical glass which reaches to optical lens standards. Each glass is coarse grinded, accurate grinded and optical processing polished on both sides. Furthermore the filters have an attenuation of coating, a nano optical coating and a water & oil coating on both sides. Double-sided precision polishing helps to reach high definition effects and ultra low color cast. The transmittance curve is rather flat from the visible light to near infrared light and the color reduction is more accurate once compared with AR ND filters. It won't cause vignetting from large angles of light coming inside accidently. The ultra low reflection on the surface can eliminate glare.
Available formats:
- Φ37mm, Φ39mm, Φ40.5mm, Φ43mm, Φ46mm, Φ52mm, Φ55mm, Φ58mm, Φ62mm, Φ67mm, Φ72mm, Φ77mm, Φ82mm, and Φ95mm
 
- 100 x 100 x 2mm/ 150x 1500x2 mm:  compatible with Mecorex, Rollie, Cokin, LEE and other 100mm/ 150mm filter holders
 
- Overview:
Nano IR Nd 4 (0.6) 2 stops
Nano IR ND8 ( 0.9) 3stops
Nano IR ND 32(1.5) 5stops
Nano IR ND64 (1,8) 6stops
Nano IR ND 512 (2.7) 9 stops
Nano IR ND1000 (3) 10 stops
Nano IR ND2000 (3.3) 11 stops
Nano IR ND4000 (3.6) 12 stops
Nano IR ND32000 (4.5) 15 stops
Nano IR ND 65000 (4.8) 16stops