Long Exposure Help

[JonathanGallagher]

Dont think im doing it right
Using a D90, Ive got M mode using ISO100 with F11 and 8secs
And the photos are just coming out with a white screen!

Also got a ND4 filter on

Hope someone can set me right :hail:

Jonathan

 

[480sparky]

Post an example.

 

[JonathanGallagher]

Just white. Nothing is showing in the image at all! Can upload tho!

 

[Light Guru]

Dont think im doing it right
Using a D90, Ive got M mode using ISO100 with F11 and 8secs
And the photos are just coming out with a white screen!

Also got a ND4 filter on

Hope someone can set me right :hail:

Jonathan

NOBODY here knows the light conditions of what you are shooting so it is IMPOSSIBLE for anyone here to say.

 

[gregtallica]

decrease aperture, decrease shutter speed until you're seeing your image




edit: increase/decrease aperture, w/e... just make the aperture number "higher".

 

[JonathanGallagher]

increase/decrease aperture, w/e... just make the aperture number "higher".

On to it now will report back!

 

[480sparky]

Camera Maker: NIKON CORPORATION
Camera Model: NIKON D90
Image Date: 2013-05-02 15:27:44 (no TZ)
Focal Length: 48.0mm (35mm equivalent: 72mm)
Aperture: f/11.0
Exposure Time: 10.000 s
Exposure Bias: none
Metering Mode: Matrix
Exposure: Manual
Exposure Mode: Manual
White Balance: Auto
Flash Fired: No
Orientation: Normal
Color Space: sRGB
GPS Coordinate: undefined, undefined
Software: Ver.1.00




OK, what are the lighting conditions? Sunny day? Dark room? Moonlit backyard? Using 12 1000ws monolights?

 

[o hey tyler]

Have you tried looking at your light meter?

 

[JonathanGallagher]

OK, what are the lighting conditions? Sunny day? Dark room? Moonlit backyard? Using 12 1000ws monolights?

Sunny trying to test it out, as you can tell first time trying it out

 

[Dao]

Set the camera on A mode instead of M. Dial the aperture to f/11 and ISO to 100 with the ND filter on. Half press the shutter button and note down the camera suggested shutter speed setting.

 

[JonathanGallagher]

Set the camera on A mode instead of M. Dial the aperture to f/11 and ISO to 100 with the ND filter on. Half press the shutter button and note down the camera suggested shutter speed setting.

Should'a known this 1/25s

Many thanks to all, Perfect now

 

[TCampbell]

OK, what are the lighting conditions? Sunny day? Dark room? Moonlit backyard? Using 12 1000ws monolights?

Sunny trying to test it out, as you can tell first time trying it out

If you "meter" your shot on a sunny day, the ND4 filter allows you to change the exposure by 4 stops.

Suppose we use the Sunny 16 rule (since you said it was sunny).

A "baseline" exposure would be ISO 100, f/16, and 1/100th (although that's just a baseline... you actually get to use any "equivalent" exposure using the exposure triangle. If you're not familiar with the exposure triangle, you might want to pick up a copy of "Understanding Exposure" by Bryan Peterson.) We know this without even using a light meter since the sun pumps out a _very_ consistent amount of light in the middle of a sunny day. So as long as we're not talking about early morning or late evening "golden hour" light or it's not a cloudy day, the sunny 16 exposure will be correct.

From that baseline, you may now slow down your shutter speed by four stops. Each "stop" of the ND blocks half the light. That means you're getting 1/2 of 1/2 of 1/2 of 1/2 of the original light (1/16th). You may now slow the shutter down by that much to compensate for it.

1/100th x 2 = 1/50th. 1/50th x 2 = 1/25th. 1/25th x 2 = 1/13th (I rounded that last one).

You didn't use f/16, however... you used f/11. f/11 is one "full" stop larger which means it let's in half the light. So now you have to back off the shutter by a full stop and return to 1/25th.

Your 8 second exposure was 32 times longer than needed... hence you got an all white image.

 

[SquarePeg]

OK, what are the lighting conditions? Sunny day? Dark room? Moonlit backyard? Using 12 1000ws monolights?

Sunny trying to test it out, as you can tell first time trying it out

If you "meter" your shot on a sunny day, the ND4 filter allows you to change the exposure by 4 stops.

Suppose we use the Sunny 16 rule (since you said it was sunny).

A "baseline" exposure would be ISO 100, f/16, and 1/100th (although that's just a baseline... you actually get to use any "equivalent" exposure using the exposure triangle. If you're not familiar with the exposure triangle, you might want to pick up a copy of "Understanding Exposure" by Bryan Peterson.) We know this without even using a light meter since the sun pumps out a _very_ consistent amount of light in the middle of a sunny day. So as long as we're not talking about early morning or late evening "golden hour" light or it's not a cloudy day, the sunny 16 exposure will be correct.

From that baseline, you may now slow down your shutter speed by four stops. Each "stop" of the ND blocks half the light. That means you're getting 1/2 of 1/2 of 1/2 of 1/2 of the original light (1/16th). You may now slow the shutter down by that much to compensate for it.

1/100th x 2 = 1/50th. 1/50th x 2 = 1/25th. 1/25th x 2 = 1/13th (I rounded that last one).

You didn't use f/16, however... you used f/11. f/11 is one "full" stop larger which means it let's in half the light. So now you have to back off the shutter by a full stop and return to 1/25th.

Your 8 second exposure was 32 times longer than needed... hence you got an all white image.

THAT is the most easily understandable explanation I have read regarding the direct relationship between aperture and shutter speed and the use of ND filters. All the others I have read made sense but didn't click. Thanks. Saving that one!

 

[480sparky]

........You didn't use f/16, however... you used f/11. f/11 is one "full" stop larger which means it let's in half the light......

F/11 lets in twice as much light as f/16, not half.

 

[TCampbell]

........You didn't use f/16, however... you used f/11. f/11 is one "full" stop larger which means it let's in half the light......

F/11 lets in twice as much light as f/16, not half.

Sorry and yes Sparky is right. My brain does that from time to time... you gotta watch me.

As the f-stop number gets smaller, the opening gets larger.

The full stops are f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, and f/32 (and you could go on but it's rare to find a lens that goes beyond f/32). You might wonder why they're not simpler sequential numbers. The numbers are based on the powers of the square root of 2 (approximately 1.41) That's because when the diameter changes by the square root of 2, the area changes by either double or half (depending on whether you're getting larger or smaller).

11 (for f/11) is a rounded value of the square root of 2 raised to the 7 (√2^7). 16 (for f/16) is √2^8. Notice the power changed from 7 to 8. That's one "full" stop... f/11 is twice the area of f/16.