Not an auction
However we should see a Dream
https://www.ebay.com/itm/22551625144...gAAOSwJmZikPdi
Not an auction
However we should see a Dream
https://www.ebay.com/itm/22551625144...gAAOSwJmZikPdi
Tin Can
It is a 'rectifying enlarger' for correcting perspective in aerial photography. Originally a Wild model, I think.
Good luck at that price. Aerial photography, like most professional applications, is almost entirely digital now. This thing is about as welcome as a process camera with an 8 foot bed - "Get this thing outa here..."
Darkroom Automation / Cleveland Engineering Design, LLC
f-Stop Timers & Enlarging meters http://www.darkroomautomation.com/da-main.htm
Does anyone have an explanation for the 9x9" format. If they made it ONE INCH larger it might have caught on!!!![]()
Aerial roll film. It could have had military surveillance or perhaps mapping applications post-WWII, black and white film only. Bigger and far more sophisticated color 9X9 enlargers related to U2 flights were being used by the NSA up to around 20 yr ago, or possibly even a little more recently. Actual film has real advantages over satellite imagery, including much higher detail and the ability for decision-making non-specialists to intuitively evaluate things for themselves. Also, anyone who has stereoscopically viewed sequentially aligned overflight images knows how much better they reveal 3d details than Google Earth, for example. But satellite and drone imagery can be conveyed almost instantly in real-time; and large film and sizable printing had an arduous workflow, including skilled maintenance of those big specialized enlargers, and a continued supply of necessary parts, neither of which exist anymore.
That's basically how the USGS had mere humans draw all those 7.5 TOPO maps -- by hand.
Those topo maps were all done machine-stereoscopically, a fairly old but highly accurate method provided the planes flew exactly straight at exactly the same speed. The handwork just filled in the outlines of natural features like glaciers, or artificial ones, or known trails, plus place names. The contour lines were all machine plotted using a parallax differential accentuated by distinct color filters, much like a 3D movie. Actual handmade topos? - that was ground-based, and what we had to learn in Geology and Archaeology classes using a transit. Nearly all the US topo maps were made at the USGS facility at Menlo Park. Then this data base get used to generate all kinds of private maps, including on navigation devices.
When I was young I'd borrow the oldest sets of overlapping 9 inch stereoscopic images I could find and view them through red and green filter stereoscopes. Hards on the eyes; but one can pick out geological and archeological details in an amazing way - or military ones if that is their job. Major battles in WWII were done by women doing that kind of thing all day long. But the problem is that is there was a cloud-free day ideal for this kind of mapping, the enemy could see the plane too and shoot at it. Of course, the Germans themselves were pioneers in aviation optics, so had a good reason to shoot at solo planes flying overhead.
One dirty little secret I learned when my nephew was earning his University expense income by being employed in both Fed and private mapmaking is that nearly all private companies add a few deliberate errors to their own maps to catch any plagiarism - streets that aren't really there, roads and lakes out in the desert. I'll stick with real USGS topo maps or maps which have licensed their own details. Less risky than using a navigation device which takes you on a "shortcut" route way out in the desert toward a lake that doesn't exist, to where the rutted road runs out, along with your gas too. Just remember that possibility if a bunch of vultures try to follow you on the left turn off the main highway.
Even Google satellite has anomiles as many have found
Also the wealthy get to hide their holdings
Tin Can
I'm not sure that all of the errors in modern digital maps are deliberate. It appears that now Google Earth and competitors use computer programs (AI?) to recognize roads etc. and to put in their road layers. I've been doing fieldwork in the Dominican Republic, have used maps from OpenStreetMap in my routing GPS and to find likely sites (access to rivers). Always check against satellite photos (Google Earth, planet.com) to make sure that a bridge crossing a river isn't a misidentified pipeline, have noted that even small roads clearly visible in satellite photos can't be seen when on the ground. Have found GE's river names unreliable.
Google Earth is a patchwork of satellite images, some over a decade old, and often taken over different seasons with bizarre interfaces of winter versus summer conditions. Right now, all kinds of roads and bridges in my hometown region of the Sierras simply are no more due to washouts the past few months. Likewise, it's fun to home in on backcountry trails on Google Earth 3D; but that doesn't tell one their current condition after a winter of severe avalanches and landslides. What's more up to date are the street address shots being taken by those little Google drive-by cars with their whirling cameras atop - the burglar's dream tool, along with little drones.
The stereo images were taken along a flight line with one airplane. They just over-lapped the images along the line about 60%. Images from parallel, adjacent flight lines over-lap as well (about 30%), but not for stereo purposes, just coverage. The USGS used a Kelsh plotter for the contour lines, and these were drawn by hand while guiding a point that looked like it was in contact with the ground at a given elevation. The USGS Circular 357 describes the method (see page 1, Chapter 3F5). I remember using a Kelsh plotter at the University of Idaho about 43 years ago, but just for training purposes. It is very tedious work.
Once they were standardized, aerial photos for most work were on 9 by 9 inch negatives, and contact prints were the norm. But agencies could order enlarged prints (I have seen them up to around 24 by 24", dating to the mid-1940's. I am working with some now, from the North West Rivers Survey by the US Army). The US Fish & Wildlife Service used color infra-red transparencies (9 by 9) for wetland delineation. Topography was not important, but detail on plant stress etc. was very helpful and the IR wavelengths picked this up (water-stressed plants are less red, or even green). The detail was amazing.
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