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View Full Version : Get a Flowing Cloud Effect?



cmaw63
05-18-2008, 08:59 PM
I've searched the forums and tried googling articles. I still do not have a clear idea on how to capture a soft cloud movement in my photos. I tried today and all I got was a completely white picture.

I set the shutterspeed at 2 seconds, played around with different apertures and had a polarizing filter on. All produced the white picture. Any ideas on what I did wrong?

Thanks

TheWengler
05-19-2008, 01:22 AM
You're over exposing the image. You'll need an ND filter to correctly expose with a shutter speed that long on a bright day. Stop down to f/16 or so, set your camera on the lowest ISO then see what shutter speed you get in the kind of lighting conditions you want to shoot in. Then use that to figure out how many stops away from you're desired shutter speed you are. Then get the appropriate ND filter. I imagine you'll need something like 8 stops to get a 2 second exposure.

cmaw63
05-19-2008, 07:01 AM
I already have a ND on the way so I'll wait for it to get here to try again. I appreciate your answer more than you know...you summarized in one paragraph, in a way I could understand, what others have put in articles and fluffed it so much I couldn't understand a word of it.

Thanks!

namesalex
05-19-2008, 01:44 PM
You're over exposing the image. You'll need an ND filter to correctly expose with a shutter speed that long on a bright day. Stop down to f/16 or so, set your camera on the lowest ISO then see what shutter speed you get in the kind of lighting conditions you want to shoot in. Then use that to figure out how many stops away from you're desired shutter speed you are. Then get the appropriate ND filter. I imagine you'll need something like 8 stops to get a 2 second exposure.

what do you mean by 8 stops?

TheWengler
05-19-2008, 02:04 PM
what do you mean by 8 stops?

Aperture...f/16, f/11, f/8, f/5.6, f/4, f/2.8...
Shutter Speed...1/100, 1/50, 1/25, 1/13, 1/6...
ISO...100, 200, 400, 800...

These are the three things that control the exposure of your image. Advance any one of them to the right and it doubles the amount of light your camera takes in. Move the other way and you cut the amount of light in half. By saying "8 stops" I mean that when the camera is set at ISO 100 and f/16 there's 8 increments (full stops) between shutter speed that would produce a correct exposure and the desired shutter speed. An ND filter can be used to bring these closer together.

namesalex
05-21-2008, 12:19 AM
i just read the first 45 pages of Understanding Exposure and now its all clear to me! :D