ND filters

[Rick50]

Great explanation. Can't get much clearer than that...

 

[MitchStrp]

If I am going to spend money on something, I'd do enough research to know what I want to know first. That's just me.

So everything you HAVE and WILL purchased in your life has been well researched and thought out? Dont be that guy to harass the new guy.. I am trying new things, I am new to this hobby and am experimenting, dont take the fun out of my new hobby...
Thanks for not being THAT guy

 

[Majeed Badizadegan]

An ND filter changes your shooting circumstances. It alters the possible aperture & shutter speed combinations that you can use to take the shot.

There are a handful of ways to describe the same concept on an ND filter. Your filter is using density values. Each ".1" density is equal to 1/3rd of a "stop" of light. That means .3 is a full stop and .9 is 3 full-stops.

A "stop" is a term from the days of mechanically adjusted apertures that had "clicks". In the industrial revolution, lots of machines had mechanical levers and dials. To hold the lever in place you would have some mechanism for the lever to click into teeth or indentations as you adjusted it. Those teeth or indentations were called "stops" because they stopped the lever from moving. Since that's when cameras came into their own, the term was adopted and even though it's all electronic and there are no mechanical indentations or teeth, we still call them "stops".

The "stops" were set up so that each time the size of the aperture increased or decreased in area enough to exactly "halve" or "double" the amount of light that could pass through, it was regarded as a "full" stop. We do the same for the shutter speed... each time the shutter speed either doubles or halves we also call that a "stop".

A 1-stop ND filter (0.3) is allowing exactly HALF of the light to pass through and blocking the other half.
A 2-stop ND filter (0.6) allows HALF of that HALF... or a grand total of ONE QUARTER of the light to pass through and blocks the rest.
A 3-stop ND filter (0.9) allows HALF of the HALF of the HALF (notice I said "HALF" three times) or a grand total of ONE EIGHTH of the light to pass through.

Since you're blocking the light optically using a filter (rather than the shutter speed or the aperture) you're free to use slower shutter speeds (you can leave the shutter open eight times as long to compensate for the filter) -OR- you can open up the aperture on the camera more to create a narrower depth of field.

Most of the time when we use an ND filter it's because we're outside in bright sun. Even at ISO 100 and f/16 (a fairly narrow aperture) we still have to keep the shutter speed at 1/100th or we'll have an over-exposed shot. But if we use a 3 stop ND filter we can cut the shutter speed down to about 1/15th or even 1/10th (since there is no 1/12th shutter speed). This means that if you were shooting a photo of a waterfall, rather than a frozen waterfall where you can see every drop in mid-fall you get nice blurred effect. If you went even slower you could get an even smoother effect, but you'd need a stronger ND filter to do that.

There are ND filters so dense that you can't really see through them for purposes of focusing the camera or framing up the composition of your shot. You have to setup the shot with the filter off the camera, then put the filter on the camera to shoot.

Right. This filter is called a 10 stop filter, and it cuts out ten stops of light. It is also called "black glass" and has increased in popularity in the recent years for the effects it can give photos. Some popular effects are turning a tumbling sea into a soft, flat plane or making clouds appear to be streaking through the air, likes strokes of a paint brush.

Personally, I own the 10 stop filter but OFTEN wish I had a two or three stop filter. 10 stops is often far too much stoppage for normal situations.

There's a constant battle of the moving parts to maintain the best image quality and also reach the desired effect in the image. If you want to shoot a waterfall in the afternoon at 1/3 sec, to give it a silky look, without filters this is often impossible. If you shoot at very narrow apertures, such as f/22, you are introducing lots of diffraction into the image, which results in reduced image quality.

The filter you have now allows you stay within a range of sharp apertures, and attain the shutter speed you want for the desired effect. That battle is for the best image quality is still going, however, because now you've introduced a new piece of glass. Your image quality is only as good as your weakest piece of glass! So that's why it's a good idea not to skimp on filters. They are a lifetime investment.

Although all filters will degrade image quality to some extent, the high quality ones like B+W, SinghRay, and LEE, will impact the image quality the least.

Having this filter should give you a lot of flexibility to expose the way you want to for the effects you want.

 

[Majeed Badizadegan]

So everything you HAVE and WILL purchased in your life has been well researched and thought out? Dont be that guy to harass the new guy.. I am trying new things, I am new to this hobby and am experimenting, dont take the fun out of my new hobby...
Thanks for not being THAT guy

Well since you're flipping off the world in your avatar, and you're the "new guy", the responses you've received in this thread are pretty mellow relative to what the norm is around here.

 

[ph0enix]

Why did you buy it if you don't know what it does? What do you want to use it for?

ND filter reduces the amount of light entering the lens given the same amount of time, without affecting image quality or color.

Usually it's for shots that want to use long shutter speed. For example, if you want to shoot moving cars or pedestrian(motion blur) in the day, the day light is too bright to have long shutter speed without over exposing the shot. Using a ND filter will allow longer shutter speed given the same aperture setting. So you don't need to do any adjustment to your camera. Just set it in Aperture mode, set it to your desired aperture and observe the shutter speed. See if that will get you the effect you want. Usually, this is done on a tripod.

A 0.9 ND filter reduces the exposure by 3 stops. So for example, in day light, a setting of F8 @ 1/250 will become F8 @ 1/30.

Never said I didnt know what it was for.. Wasn't quite sure of the adjustments required to get full effect.

Clearly you're trying to run before you know how to walk. You may want to start here:
http://www.thephotoforum.com/forum/...-forum/267492-info-those-new-photography.html

 

[Vautrin]

Fun things to try with ND filters:

1. Get a tripod and screw on your ND filter
2. Go somewhere busy... Lots of people
3. Frame your shot. Set iso as low as she'll go, and your aperture as small as it gets (maybe f22, or f16)
4. Take your shot -- even in bright daylight you can get 30 second exposures or more, if you're lucky
5. Look at the shot. You'll notice people have disappeared from the photo even if they walk in front of the camera. Or, if you set it up for a faster shutter speed (say 1 second) maybe they'll just be a blur

 

[ratssass]

Fun things to try with ND filters:

1. Get a tripod and screw on your ND filter
2. Go somewhere busy... Lots of people
3. Frame your shot. Set iso as low as she'll go, and your aperture as small as it gets (maybe f22, or f16)
4. Take your shot -- even in bright daylight you can get 30 second exposures or more, if you're lucky
5. Look at the shot. You'll notice people have disappeared from the photo even if they walk in front of the camera. Or, if you set it up for a faster shutter speed (say 1 second) maybe they'll just be a blur

what exactly causes that?I was playing around w/long exposure one night a few years back,trying to get streaky tailliights of passing cars.....in some images (the longest ones) the streaked taillights were there but no car.

 

[480sparky41 40]

what exactly causes that?I was playing around w/long exposure one night a few years back,trying to get streaky tailliights of passing cars.....in some images (the longest ones) the streaked taillights were there but no car.

The taillights are a lot brighter than the cars. The cars were so dark, they didn't register an image on the film/sensor.

 

[ratssass]

here are 2 of those shots..both 2 second exposure...

actually,i'm more interested in the people disappearing in long exposures.Is there a name for this effect/technique,that I might be able to research,so as not to ask too many questions,before I've done my own research?

 

[480sparky41 40]

here are 2 of those shots..both 2 second exposure...



actually,i'm more interested in the people disappearing in long exposures.Is there a name for this effect/technique,that I might be able to research,so as not to ask too many questions,before I've done my own research?

if you look close, the cars ARE there. But they're 'smeared' across the image just as much as the taillights. If you look, you'll see the image is darker where the car passed through.