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GH85Carrera GH85Carrera is offline
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Join Date: Nov 2007
Location: Oklahoma
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Quote:
Originally Posted by red-beard View Post
Part of the issue is the lens. How detailed do you think you can be at 100 miles versus 12 miles? As an example, people wonder why we can't zoom in to the Apollo 11 site. The entire site is more than a pixel wide for the best camera on the Hubble Space telescope.
That is a big part of it, you are right. We had the 3rd to the last Leica made RC30 film camera ever made. It sucked up 9 inch wide film ($2,750 per roll processing was additional). Each exposure was a 9x9 frame of film. The lenses had reached the limit of resolving capability to be both sharp and accurate. We had to spend 20 grand every three years to send the 500 pounds of camera and lens to be serviced, then send to the USGS to be "calibrated" and all they did was measure the resolving power of the lens and the accuracy. To be any sharper the lenses picked up distortions in other parts of the lens.



This is the lens. It was a 150mm lens, (6 inch focal length) that covered edge to edge of a 9x9 piece of film. It weight over 120 pounds and the entire RC-30 system was on bargain price move it out the door price for 490 grand. It went in a Cessna 206 with a 22 inch hole in the floor that was put in by Cessna when the airplane was made.

If we went up to 6,000 feet above the ground we could shoot one entire square mile at a time, and achieve a 6 inch pixel when we scanned the film at 12 microns (just over 2,000 PPI) with a scanner that cost 70 grand.
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42 Year member of the Porsche Club of America
1985 911 Carrera; 2017 Macan
1986 El Camino with Fuel Injected 350 Crate Engine
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Old 02-18-2019, 12:55 PM
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