You want to have a light source that comes from below, either a high powered lamp, flashlight, or your flash (preferred)
Place it right underneath the subject's face so you get lots of creepy shadows, and get them to make a scary face.
If you are using Manual(M) shooting mode, make sure that you take your meter reading more from the brighter areas (zoom in on them or use your spot meter)
If you are using Shutter(TV/S) or Aperture Priority(A/AV) mode you will most likely have to set your exposure compensation(+/-) to the MINUS, probably -1 or -2. ( Remember to see it back to zero when you are done!)
If you are using your flash, you will need to use an off camera flash cord or trigger it wireless and hold it under the person's face. Try a manual setting of 60th/second at F16 or F22, and adjust the flash power as necessary!
You can also get interesting effects outdoors!
The first thing you need to do is get the subject backlit, or in the shade. That way they will be dark, and you can add the light with the flash. Check out this post about using more than one flash to overpower the sun for my series of Canada Games portraits
This is easier to do on an overcast day, as the light is lower.
You will need to use the follow settings:
MANUAL mode (M)
SHUTTER SPEED: The highest number your camera will allow you to shoot with when using the flash. For most cameras, this will be 1/200th of a second
APERTURE: If it's fully sunny outside, you will most likely end up shooting at F22, higher if you want to overpower and darken the ambient.
FLASH: Manual flash mode is better. You will most likely have to set the flash power to FULL since you are shooting at F22, and get the flash close. You could also use TTL.
FULL POST WITH MORE IDEAS AND ALL THE TECHNICAL CAMERA INFO NOW AT WWW.LEARNPHOTO365.COM
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