Whis a ND Filter

norgeanders

norgeanders

Active member
what is a ND filter or fader filter or whatever i here people talking about it all the time but i don't understand what they are and why there so expensive

Thanks
 
thanks a lot!! i have googled it but it was cool how it did it for me!!..not

i understand that its essentially just a filter but i don't understand why they can be so expensive and they look like a polarizer filter?
 
Neutral Density filter. as eheath said.. it's like putting sunglasses on your camera.

you can then film at f/8.0 in full sunlight while maintaining a proper exposure.

Or if you're using it for photography, you can do long(er) exposure shots during the daytime/under bright light conditions.

....which is pretty much exactly what Wikipedia says it does. And Wikipedia was the first thing that came up when I Googled it.
 
Okay...

When you're shooting video with an HDSLR you have three variables that control your exposure

ISO

Aperture

Shutter Speed

These all control both exposure and have a seperate effect on the image.

ISO - if you raise the number you get more digital gain in your image or "noise" it also increases the exposure

Aperture - When you set it to a lower number and open it up you increase the exposure and earn a shallower Depth of Field, essentially the shallower the DOF the faster things fall out of focus as they move away from the optimal focal plane.

Sutter speed - when you use a lower number you increase the exposure. The shutter speed also controls motion blur in your image. A slower shutter speed has more blur and a faster shutter speed has less blur as things move through the frame.

People like to have control over all of these elements and that's where an ND filter comes in.

Say you're shooting in bright sunlight. Without an ND filter your image is properly exposed at ISO 100, F/16 (aperture), and 1/125 (shutter speed).

Now you have a very busy background and it's distracting. You want to isolate your subject and can only use available light. Naturally you'd opt for a shallower depth of field.

However, when you open up your aperture in order to narrow your DOF your image gets over exposed. You're ISO is already as low as it can go so your only option to properly expose your image is to increase your shutter speed.

Unfortunately this increase in shutter speed makes your footage look very choppy, you get strange artifacts when your subject makes quick movements. When the shutter speed was at 1/125 the image looked much better.

So what you do is slap on an ND filter. This filter darkens the overall image so you can bring that shutter speed back down to 1/125th or something close to that and your shot looks exactly the way you wanted.

Does that make sense?
 
- They're expensive because quality products are.

- And they look like a polarizer because they don't. Just because it's dark too doesn't mean it's a polarizer.

For gods sake, do some research on your own.
 
highjackin this thread. What do you guys recommend getting first, ND or Polarizer?

If ND which level?

Thanks, +k for hep
 
completely depends what you shoot

want to do a lot of long exposure photos? get a 9/10 stop ND

want better colors for filming/general photos? CPL
 
The purpose of an ND is to make the image darker without effecting the colors, hence the name "neutral density." The purpose of a polarizer is to polarize the light as it enters the lens, boosting contrast and colors. It can also be used to see through glass reflections. Two completely different tools.

If you simply need to darken the image so that you aren't stopping your lens down all the way, then you need an ND. Polarizers are useful too, but even with a polarizer you will need an ND if you're outdoors. In my opinion, any ND less than .09 is worthless for video. Tiffen makes a decent one.
 
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