0
$\begingroup$

First off I am very new to 3D modeling. So please forgive any glaring mistakes.

I am trying to create a scene that simulates satellite imagery using Blender render. When I render any thing but the simplest mesh object like a cube I get black chunks all over the object. However if I move the camera close to the object those spots disappear. The only difference between the cameras is location and focal length. What am I doing wrong. Any help would be greatly appreciated.

Here is my .blend file if it will help. Example

(150km) Camera Render of a UV Sphere (150km) Camera

(50m) Camera Render of a UV Sphere enter image description here

$\endgroup$
  • 1
    $\begingroup$ One suggestion would be to adjust your camera clipping settings. I'd be happy to take a closer look if you can post your file :) $\endgroup$ – moarorleslie Mar 27 '18 at 22:58
  • $\begingroup$ I made sure the clipping end was set to 600km. Here is a link to the .blend file link $\endgroup$ – hdbgdz Mar 28 '18 at 16:45
  • $\begingroup$ It's stranger than just black spots: if the world colour is changed to a brighter horizon value, the spherical hull seems to reveal the dashed pattern underneath. It would appear that a camera that distant, with the field of view corresponding to minuscule angles, is causing some errors, but I'm not sure as I'm not too familiar with the inner workings of the original blender internal renderer $\endgroup$ – Nicola Sap Mar 28 '18 at 17:32
  • $\begingroup$ How do I reproduce your error? I don't see the black spots, I tried moving the camera close and far, and it looks fine. $\endgroup$ – moarorleslie Mar 29 '18 at 3:30
  • $\begingroup$ Perhaps it is my computer, but when ever I place the camera more than 10 or so kilometers above the target the render looks like the first image. $\endgroup$ – hdbgdz Mar 29 '18 at 18:09
0
$\begingroup$

Adding the answer for completeness!

From the above comments, I compared the "Sat" camera object with a "good camera". The focal length of sat was set at 13 meters vs 3.8mm in the default camera. I think the largest focal length lens in real life is way smaller, so maybe that's why it got all screwy. Anyway, if you change the focal lens size to 3.8mm or some other realistic size, you should be good! You will also need to move the camera closer to the object.

$\endgroup$
  • $\begingroup$ That is indeed what I ended up doing. I think I was just making everything more complicated than it need to be. Since I am not simulating the curvature of the earth or the atmosphere between camera and target it is a lot simpler to shrink the focal length of the camera and move it closer. $\endgroup$ – hdbgdz Apr 6 '18 at 17:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.