Why wont my pictures work with slow shutter speed.?

Question

Whenever i take a photo with a slow shutter speed, anywhere from 8" to 30, all the picture is just white-out. I closed my apperature as much as i could but nothign but white photos. I'm trying to get cool effects from waterfalls and swaying long grasses and such. Anyhelp?

Answer 1

If you are getting a totally white pic it's because the shutter is staying open too long and washing out the photo with too much light exposure.  Try raising the shutter speed, one step at a time, till you get the effect you want.

Answer 2

You are over exposing. You have way too much light for the settings you have set on your camera.

You will need a neutral density filter to block out even more light.

Consider this, assuming the sunny-16 rule, if you had your film speed at 100 ISO (generally the lowest on a DSLR), at f/16 you would need a shutter speed of 1/100 sec. This, btw, is a reasonable exposure on a sunny day.

Assume you can stop down your aperture to f/32 - that is only two more stops. That means, at best you can slow your shutter speed to 1/30sec (two stops worth). And you can't lower your ISO any further.

So, if you shoot at 8 seconds, you are over-exposing by:

1/30

1/15 +1

1/8   +2

1/4   +3

1/2   +4

1      +5

2      +6

4      +7

8      +8

15    +9

30    +10

EIGHT stops!!

at 30sec, you are overexposing by 10 stops!

You need a ND400 filter: http://www.camerafilters.com/detail.aspx...

This is a great filter - I use it quite often.

Answer 3

Are you sure you're closing the aperture the right way? Remember, the bigger number is the smaller aperture.

Also, you may want to try using a smaller ISO as well (smaller number).

Another option you have is doing this in shutter speed priority mode. You set the shutter speed, the camera sets the rest.

Good luck!

Answer 4

You are overexposing the image.  You need to take at least a beginning photo class to learn all about exposure and reciprocity.  

The way to reduce the amount of light entering the camera during long exposures is to add enough ND to the front of the lens to allow longer exposures.  When shooting waterfalls, I shoot them when they are in the shade and using a 4ND filter and add a polarizing filter if I need to reduce the light a little more

Answer 5

For each doubling of the shutter speed, you have to close the aperture down by one stop. So if f/8 at 1/125th is the correct exposure, you need something like f/256 at 8 seconds. First, you don't really need more than about a second to get a nice blur on a waterfall. Use the lowest ISO you can,  add a neutral density filter to the front of your lens to reduce the light, and shoot early or late in the day when it's not so bright. Also, most cameras will indicate whether your exposure is correct, even in manual mode.