Quote:
so I'm assuming that all the data contained within the file describes only the circle of radius 2.5 degrees from the south pole, rather than a rectangular swathe of geography centered on the pole, and therefore when we present it as a rectangular image, we're actually stretching it's true geography in the corners.
No
the corners are higher lat of the image
it is just NOT cropped
Quote:
I'm not trying to do a complete spherical moon, but rather the idea is to place a patch of geometry at the polar region. (Same idea as what Selden did with his Mt Palomar telescope, IIRC).
i would use isis , but GDAL should be able to crop it ( in isis it is putting a check in a check box and running it to crop out the extra px and make it a circle )
the curvature from the center to the edge is not going to be much
i am on my first cup of coffee for the day so -- no math
calculate the height of a part of the sphere with a plane bisecting at -87.5 and the center at -90
ad a burn mask to the image , add the two images together
and use the gmic to .off mesh code
in the very last post , right above this
Code:
MAP_RESOLUTION = 1516.17 <pix/deg>
when i was remapping it to work with a smaller image
at 128 ppd it is a image that is 641x641 px