Neutral Density Filter

[echoyjeff222]

Hi all! I am finally getting back into photography now that it's summer and school's out. I had a pretty lame question, but it's worth a shot ... is it possible at all to use a film camera neutral density filter on a digital camera? My digital camera doesn't come with any filters at all (can't even change lenses!) ...

I'm trying to do some long exposures of water in the daytime, so that was the reason. Are there any alternative ways to go about reducing the light hitting the lens (besides the usual setting changes?)

Thanks!

 

[Light Guru]

is it possible at all to use a film camera neutral density filter on a digital camera?

They don't make ND filters for film and ND filters for digital, they just make ND filters.

 

[Centropolis]

First off, like what Light Guru said there are no different ND filters for film and digital. Same stuff.

As for other alternatives to what you're trying to do, there isn't anything that I can think of at all. You'd have to reduce the amount of light that is hitting the sensor so some kind of filter is needed. The only thing I would mention is that if you already own a circular polarizer for the lens you're going to use, it does reduce light by about 2-stops. But 2-stop may not be enough for what you're trying to do.

 

[Gavjenks]

Circular polarizer + variable ND filter will not only reduce reflections and make skies prettier and such, but combine to up to 12 stops for your average models. + a tripod, you can go a good solid 7 stops slower on shutter speed than the metered exposure. And probably another 7 stops slower in ISO + aperture than you might normally use to take a non-intentionally-blurred photo in the same conditions.

So the filters will give you twice as much flexibility, and ~4,000x less actual light than the other tools at your disposal alone.

The combined 26 stops is... a lot. Several stops more than the difference between Bright sunlight shining on snow versus pitch black asphalt under starlight.

 

[Helen B]

High end ND filters for digital also cut infrared. Film ND filters don't need to do this because most film isn't sensitive to IR, so they didn't necessarily cut IR. Many digital sensors have some sensitivity to IR despite the IR-blocking filter, so when light is heavily attenuated by a filter but IR radiation isn't there can be a problem with IR 'pollution'. Best thing is to try it and find out if it is a problem.

 

[Helen B]

Circular polarizer + variable ND filter will not only reduce reflections and make skies prettier and such, but combine to up to 12 stops for your average models. + a tripod, you can go a good solid 7 stops slower on shutter speed than the metered exposure. And probably another 7 stops slower in ISO + aperture than you might normally use to take a non-intentionally-blurred photo in the same conditions.

So the filters will give you twice as much flexibility, and ~4,000x less actual light than the other tools at your disposal alone.

The combined 26 stops is... a lot. Several stops more than the difference between Bright sunlight shining on snow versus pitch black asphalt under starlight.

How do you get 26 stops?

 

[echoyjeff222]

Wait, so should I just go and try on the ND filter for film and hope it fits the digital lens that I have?

 

[480sparky]

Circular polarizer + variable ND ..........

I would hate to see the weird exposure variances you get across the frame with that set-up.

 

[TCampbell]

Circular polarizer + variable ND ..........

I would hate to see the weird exposure variances you get across the frame with that set-up.

A variable ND is really two polarizers stacked together. When you add a third polarizer, they can actually cancel each other out (depending on the angle) and let light pass as though you don't have any filters at all.

Here's a video demonstrating the effect:

 

[Helen B]

If the extra polarizer is circular polarizer the effect of stacking it with a VND will be different from that of a extra linear polarizer. The VND may itself use two C-Pols, with the polarizer foils facing the centre and the delay plates outside. You are still asking for trouble, of course.

 

[480sparky]

Circular polarizer + variable ND ..........

I would hate to see the weird exposure variances you get across the frame with that set-up.

A variable ND is really two polarizers stacked together. When you add a third polarizer, they can actually cancel each other out (depending on the angle) and let light pass as though you don't have any filters at all.

]

I'm referring to the X-effect you get when you dial down a VND to maximum.

 

[Gavjenks]

Circular polarizer + variable ND filter will not only reduce reflections and make skies prettier and such, but combine to up to 12 stops for your average models. + a tripod, you can go a good solid 7 stops slower on shutter speed than the metered exposure. And probably another 7 stops slower in ISO + aperture than you might normally use to take a non-intentionally-blurred photo in the same conditions.

So the filters will give you twice as much flexibility, and ~4,000x less actual light than the other tools at your disposal alone.

The combined 26 stops is... a lot. Several stops more than the difference between Bright sunlight shining on snow versus pitch black asphalt under starlight.

How do you get 26 stops?

10 from a typical variable ND filter set to max
2 from polarizing filter stacked
okay more like 10 at least from from shutter speed due to a tripod (can go from 1/20th or so handheld at best to 30 seconds with no remote)
4-5 or so from ISO and aperture. if one assumes a boring/average f/8 and ISO 400 or so, you could go down to 100 and f/4.

4 + 10 + 2 + 10 = 26

 

[Gavjenks]

A variable ND is really two polarizers stacked together. When you add a third polarizer, they can actually cancel each other out (depending on the angle) and let light pass as though you don't have any filters at all.

Did you actually watch the video?

When he added another linear polarizer on top of the two that would be a ND filter, it did absolutely nothing. Only if he put it in between, which of course doesn't happen when stacking filters.

Furthermore, it's a circular filter, not another linear one, so who knows?

Well, I know. Because I just tested it 10 seconds ago, and adding the CP filter on top of a maxxed out ND filter did... something. In fact, it darkened the whole exposure by 2 stops. Ta da! They do indeed work additively.

 

[bratkinson]

In looking at the OP's gear list, he has a Nikon Coolpix P90.

I'm a Canon shooter. So I looked up the P90. It doesn't even look like there are any kind of filter threads on the lens of the camera. So, mounting a filter will be almost impossible unless there is some kind of optional accessory to mount a filter. Perhaps some square filter adapters exist from Cokin or other companies that use some kind of 'hose clamp' to attach the adapter. I don't know. While simply holding a filter in front of the lens might work, perhaps a separate tripod could be used to accomplish the same thing without the negative effects of long time (in seconds) for hand holding a filter.

 

[Helen B]

Circular polarizer + variable ND filter will not only reduce reflections and make skies prettier and such, but combine to up to 12 stops for your average models. + a tripod, you can go a good solid 7 stops slower on shutter speed than the metered exposure. And probably another 7 stops slower in ISO + aperture than you might normally use to take a non-intentionally-blurred photo in the same conditions.

So the filters will give you twice as much flexibility, and ~4,000x less actual light than the other tools at your disposal alone.

The combined 26 stops is... a lot. Several stops more than the difference between Bright sunlight shining on snow versus pitch black asphalt under starlight.

How do you get 26 stops?

10 from a typical variable ND filter set to max
2 from polarizing filter stacked
okay more like 10 at least from from shutter speed due to a tripod (can go from 1/20th or so handheld at best to 30 seconds with no remote)
4-5 or so from ISO and aperture. if one assumes a boring/average f/8 and ISO 400 or so, you could go down to 100 and f/4.

4 + 10 + 2 + 10 = 26

Sorry, I thought that you were on topic and talking about 26 stops of usable attenuation. By the way, I think that you might have got mixed up in your ISO-aperture figures. You've given equivalents.