Re: Camera Obscura -- San Francisco

[Simon Nathan <simonwide@xxxxxxxxxxxxx>]

LOOK IN MARCO'S WONDERFUL INDEX OF THIS LIST.
THEN SAY "THANKYOU, MARCO." SIMON NATHAN

GAPiccagli@xxxxxxx wrote:

Hello Pinholers,

I have just returned from my first visit to the Camera Obscura in San
Francisco. I was interested in several aspects.

1) As the turret rotated, we saw both landscape nd the building behind us,
which was much closer. The building behind us did not seem as sharp as the
landscape. This surprised me as I thought pinholes had essentially infinite
depth of field -- though I am aware that optimization formulas for infinity
differ from those for "macro" pinhole work. Is it possible that the
building's size relative to its distance made it a "macro" object rendered
with less definition? Or am I simply imagining things?

2) had a nice chat with the ticket-taker, not the owner. He indicates that a)
traffic seems to be up as a result of media exposure and b) the saving of the
camera by relocation to the roof of a nearby building is not a done deal.

3) He asked a) how many camera obscuras there were in the US and b) their
location. I remember a posting with that information a little after the
brouhaha started. Could someone repost it?

Thanks.