Lunar rectified images / shifted perspective, Clavius

[Joseki]

I've been reading Charles Wood's "The modern moon", in which he describes a technique for shifting the perspective of features that appear distorted as they lie close to the lunar disc edge (they projected the image onto a plain white sphere and re-photographed it from a different perspective).  - This led to the recognition of the Mare Orientale.  This seemed like a pretty interesting idea which I wanted to be able to do (with software of course),  I then found examples of people doing just that on the web - though the examples seemed to be with an outdated version of some software.  Anyway, I had a go and although I'm still learning about how to get the best results I'm happy enough with my proof of concept results.

To do this I used blender v2.7 -  free 3d rendering software (2d/3d manipulation, very useful software which my summary of it doesn't appear to do justice to).  The technique is called UV mapping and there are plenty of example videos on the you tube on how to map a 2d image onto a sphere

(this one is a pretty good one I found https://www.youtube.com/watch?v=X3aLlpSAaH4 )

I assume it's not common knowledge as I haven't seen any lunar (or solar) images posted on SGL that make use of this to correct the effects of perspective.

I started out with this full disc mosaic I captured a couple of days ago: ( http://stargazerslounge.com/topic/218513-lunar-mosaics-6th-7th-june/ )

I was focusing in on a specific region close to the south lunar pole:

Note: Clavius is prominent in the image and even closer to the edge what I think is Moretus with it's central peak, plus Scheiner and Blancanus partially in shadow, all showing distortion because of perspective. 

I then mapped the texture onto a sphere in blender, rotated the sphere to re-position the camera angle above Clavius and re-rendered the image.  After that I got this result:

I cropped the image short of capturing all of Moretus as the distortion was getting bad at that point but I hope it's clear that this technique has had the desired effect.  btw, in blender it is straightforward to load an additional image as the background, add lighting effects and/or include several spheres within the scene to be rendered (Sun & Moon?)

[Landy Dave]

I need to give this a go as it looks very interesting

[todd8137]

Cool will give this ago as the moon is my main focus seen it before on another forum

Pat

[Knight of Clear Skies]

Very clever and nice result, thanks for posting.

[michael.h.f.wilkinson]

Very interesting. Nice result