Realistic Solar Sail in Lunar Orbit

So, I’ve set up a scene with actual starmap and moon maps, and have designed a solar sail based on this image - https://www.nasa.gov/connect/chat/nanosail_chat2.html.

I’m having some difficulty in getting the moon to reflect off the front of the sail. Its easy if I don’t try to include any serious texturing, as given by the first image. But when I include a wave texture to make the sail look less “cardboard-y” (second image) then my normals screw up reflecting the sail or any other light. If I tried to mess with the mesh instead, then I’d end up with a very high vertex count, just to avoid pixelating the large, flat sail.

Any advice on the above, or any other thoughts on how to improve the image are welcome. This will be part of an animation for YouTube.

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How are you applying this wave texture? The strength of the effect seems massively too high, or like you’re applying the texture directly to the normal input (it’s not meant for that, convert it with the bump node first).

In general, some other feedback about your image:

  • Your lunar surface map is noticeably pixelated, you’ll want to find a higher resolution one of make the moon smaller in the frame.
  • The milky way is MUCH too bright in the background. To be perfectly realistic you shouldn’t be able to see it without completely overexposing the lunar surface. In this case I think giving up realism to make it look cool is fine, but the milky way should be much dimmer than that. It will also help give the composition a nice negative space for your spacecraft to occupy
  • Add a bump map for the lunar surface (or make it much stronger if you’re already using one, I can’t tell). There should be some noticeably shadows from the craters and mountains along the terminator line, a bump map (ideally using a lunar elevation map if you can find one that lines up with your color map) will give you this effect in your render.

I’m not an expert but, I’d make 2 materials - - and, then I’d keep ’ specular ’ and, ’ roughness ’ so it’s non-reflecting on one and, another material, with high specular and, low roughness, so it reflects . . Then, go into edit mode, select the polygons ( faces ) you want to be reflective, add the reflective material ( using assign button, when selecting faces, in material tab ) and, other way for non - reflecting stuff - - that will give simple, good reflections, to some parts of mesh but, not others - - You can set ’ roughness ’ and, ’ specular ’ ( how reflective ) using standard ’ Principled Shader ’ - - Just move he sliders and, it will update in Viewport, at least in Eevee - - Good luck

Thanks for the comments J.

I am going through a bump.
So I’ve been thinking about how to handle the starmap. This is a video so I wanted to darken everything as the moon came into view, to represent the camera stepping up the filter. I was going to just put a plane in front of the camera and raise its opacity, is there a more direct way?
I’ll check when I get home tonight but I believe the moon had a bump map. (I built is a month ago) Going for realism I wasn’t sure that you would really see the crater shadows at this altitude, but maybe I should give myself some artistic license. I feel the moon looks pretty 2d in the images above.