The USDA did a huge campaign in the late 30s. Many of the better parts of the collection can be found in locsl university libraries. The trick is finding someone who knows they have it and getting access..?ÿ
I'll check into that. I download the single frames from Earth Explorer and the oldest I've found for this area is 1956. Thanks.
Oh, I see what the confusion is. The link I posted just goes to the earth explorer web page. The page I was trying to link to doesn't seem to exist anymore.?ÿ
Any area that was mapped in the 30s should have photos from then.
I will try to find some contact information on Monday when I get back to my work computer.
I have an old aerial image from 1938, but the photo is not orthorectified and the relief in the area distorts the image quite a bit. Does anyone know of a way to orthorectify old photos? Is it even possible without the metadata of the old photo?
Not really. Even with all the metadata to enable you to orientate it correctly there isn't any way from a single photo to deduce the relative heights of objects and hence correct for any "lean" (unless you already have known dimensions on the objects).
If you can find an adjacent frame, or better still the frames before and after, it might be possible to form a digital stereo model. I've done that several times using Photoscan. Plan position and height would be OK, but you won't get much, if any, realistic rendering to vertical faces (because there wasn't much to see of those on the original images).
This is mainly California but it's handy for getting old photos (not orthorectified but still useful):
There are a few things you can try, but generally speaking you're still just trying to make yourself feel good about guessing.
If you can determine the elevation of the "corners" of the frame you might have a chance. Then attempt to estimate the altitude and position of the camera from the visible parallax of power poles, structures or something like a water tower. You can then build a mathematical model as to where you think everything was at and how tilted the plate really is. Then try and check some derived horizontal distances that might be possible to field check.
Like I said, it's all still just a educated guess...especially at something like 1"=400'.
talk to https://iwitnessphoto.com/
That software is used in forensics. If you can get a couple of known distances, you might be able to gain useful knowledge from a photo. I am not sure how much is needed, but he would let you know what can and cannot be done.
