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This wonderful shot, Kodachrome I assume, was posted on one of my aviation-related Facebook pages.  Amazing they were able to get a crisp and clear image from one moving aircraft to another.

42930676_741350066210007_483839511982243840_n.jpg

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That is so beautiful.  I wish I had a time machine to see the GGIE.

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According to Wikipedia, Kodachrome at the time was rated ASA/ISO 10. The "sunny 16" rule says that at f/16, the shutter speed would be 1/10 second (this shot was obviously much faster), or 1/320 second at f/2.8, or 1/160 second at f/4.

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https://www.thisdayinaviation.com/tag/boeing-model-314/

says that the Boeing 314 engines were rated 1200 HP at 2100 rpm, and drove the props through a 16:9 reduction gear. 

Prop speed was then 1181.25 rpm, or 19.6875 rps, approx 20 rps.

20 rps = 7200 degrees per second. 

Since the prop blur in the picture appears to be roughly 30 degrees, the shutter speed was approx 30/7200 = 1/240 second, if the engines were at full cruise speed. 

If the engines were running slower, the shutter speed was longer.

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6 hours ago, waynebretl said:

https://www.thisdayinaviation.com/tag/boeing-model-314/

says that the Boeing 314 engines were rated 1200 HP at 2100 rpm, and drove the props through a 16:9 reduction gear. 

Prop speed was then 1181.25 rpm, or 19.6875 rps, approx 20 rps.

20 rps = 7200 degrees per second. 

Since the prop blur in the picture appears to be roughly 30 degrees, the shutter speed was approx 30/7200 = 1/240 second, if the engines were at full cruise speed. 

If the engines were running slower, the shutter speed was longer.

Thanks for the information.  When I used Kodachrome, it was available in ASA/ISO 25 and 64.  I didn't realize the original film stock was that slow.

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This episode of the late, great Huell Howser's PBS program "California's Gold" features all kinds of cool film, photos, and facts about the Pan Am China Clippers and their regular landings at the GGIE. Highly recommended for both classic aviation and Treasure Island fans.

California's Gold - China Clipper

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There is something very special about a world's fair built on or near water.  The photo provides clear evidence.  The World's Columbian Exposition (1893), A Century of Progress (1933-34), Paris (1937), the GGIE (1939-40) and Expo 67 (1967) made magnificent use of the water features available to them.  There were a few others, but these expositions had a remarkable charm and quality because of their use of the lake or ocean features in close proximity.

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Thanks for the California Gold link - it's great!

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I second waynebretl; thanks for the like to California Gold.  Loved Huell Howser and this program.

 

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I may have mentioned that I spent almost a year at Treasure Island attending the Navy's electronic school in 1950. It was a superb educational opportunity. In 1953, if I extended my enlistment, I was offered a teaching position at my old school, but declined because I had had enough military in my career. Twenty-five years later I would return to the Bay Area. The old Administration Building was part of the environment, and some of the GGE statuary stilled survived.

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