Bloody Marys, Camera Obscura, and Ocean Beach

This afternoon, I met my old friend, Lee, for a drink at the Cliff House. Lee and I go all the way back to 6th grade together! We reconnected a few months ago through the wonders of Facebook. We both live in San Francisco, and saw each other for the first time in over 20 years in April.

We had a nice visit today, catching up over Bloody Marys (well, a Virgin Mary for me, since I was driving, and I'm such a lightweight!). The Cliff House makes my favorite. Yum.

After we finished our drinks, we decided to go down to check out the Camera Obscura.

from wikipedia
The camera obscura (Latin veiled chamber) is an optical device used, for example, in drawing or for entertainment. It is one of the inventions leading to photography. The principle can be demonstrated with a box with a hole in one side (the box may be room-sized, or hangar sized). Light from a scene passes through the hole and strikes a surface where it is reproduced, in color, and upside-down. The image's perspective is accurate. The image can be projected onto paper, which when traced can produce a highly accurate representation.

Using mirrors, as in the 18th century overhead version (illustrated in the Discovery and Origins section below), it is possible to project a right-side-up image. Another more portable type is a box with an angled mirror projecting onto tracing paper placed on the glass top, the image upright as viewed from the back.

As a pinhole is made smaller, the image gets sharper, but the projected image becomes dimmer. With too small a pinhole the sharpness again becomes worse due to diffraction. Some practical camera obscurae use a lens rather than a pinhole because it allows a larger aperture, giving a usable brightness while maintaining focus.

I love the Camera Obscura, or the Giant Camera, as this one is called. The image is gorgeous, and totally memorizing. Lee and I stayed in there for a long time, staring at the image, and taking photos. (I'm sure he got some great ones. I only had my iPhone with me.)


Lee, taking photos of the image projected onto the screen

After we left the Cliff House area, we walked along Ocean Beach over the Beach Chalet, and the adjacent Park Chalet. I still can't believe I've never been to the Park Chalet! (my bad, Lee - next time!)


Ocean Beach

I had a really nice afternoon, catching up with an old friend. Thanks, Lee! I look forward to our next outing!