Did you identify anything about the picture? More information below the photo.
This picture was borrowed from the Lighthouse's web site.
Pigeon Point Light Station is a California State Historic Park about 30 miles south of Half Moon Bay. At 115 feet, it is one of the tallest light houses in the United States and the tallest on the California coast. It first went into operation on November 15, 1872 using a Fresnel lens comprised of 1008 prisms which projects light as in the above photograph. That lens is no longer in use and is only fired up for 2 hours each year on the Saturday closest to the aniversary date. On that night, hundreds (thousands?) of people show up to witness the event and take pictures. The deteriorating condition of the lighthouse may stop the display indefinitely and you can no longer tour the lighthouse tower itself. The grounds and museum remain open and there is a working hostel on site.
If all goes well, the next lighting will be Saturday, November 13, from 6pm to 8pm. Some tips if you plan to photograph the next event. Wear warm clothes. Get there early, before sunset, if you want to park close by. Take a tour of the grounds, the museum, the hostel and the local beach. After lighting the lamp, the lens remains stationary for 5 minutes for photographers to capture the star formation and then it begins to rotate. Hope for some moisture in the air. Fog helps to define the rays of light. You will meet lots of other photographers with tripods. Consider using a red flashlight when adjusting your equipment. It's kinder on the eyes and less chance of spoiling other's photographs.
For long exposure camera settings, I start with an F/8 aperture. That is about the best quality aperture for my D80 and gives a decent depth of field. Experiment from there. I use the lowest ISO, again for best quality. Even though it is a low light situation, the lighthouse is not moving. You don't need that wide open aperture or a high ISO. Go for better DOF and low noise instead and use a longer shutterspeed. Use a tripod. Turn off image stabilization, at least on Nikon lenses. Use a remote shutter release or time delay to reduce camera vibration. Focusing is always tricky in the dark, but the lighthouse is pretty bright, so autofocus should work. Be quick, the five minute grace period when the lens does not rotate goes by fast.
I'll probably be there, either to take pictures or as a docent. I recently volunteered to work there and begin training this Saturday.
Here is a link to their web site: The Pigeon Point Light Station State Historic Park
Thanks for playing the Friday Foto Quiz.