I have read the Blender manual regarding bump maps and normal maps. But still it is not very clear to me when you would make or use bump maps and when normal maps. Who can explain ?


1 Answer 1


Bump maps and normal maps are essentially the same thing. The primary difference is that normal maps have more information in them(because they use an rgb input) to give a more accurate bump effect. The rgb information in the normal maps correspond to the x,y,z axis.

Bump maps use only a black to white map to understand the depth.

Both bumps and normals are essentially a way to cheat the shading to give the effect of depth...meaning no resolution is added to the geometry in anyway... to do that that we use displacement maps. Displacement maps unlike the other two actually modify the geometry at render time.

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    $\begingroup$ thanks. Could you maybe explain when you use normal maps and when bumps maps ? I guess there are reasons when you chose to use the one or the other ? $\endgroup$
    – user13877
    Commented Sep 15, 2016 at 13:28
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    $\begingroup$ @OldMan - it depends on the purpose of your model. Since normal maps hold more accurate information they are the preferred method of faking geometry light reflections. There might be some older or simpler real-time 3D engines which are not able to user normal maps. Other than that, you can always convert a normal map to a bumpmap without loosing information. $\endgroup$ Commented Sep 15, 2016 at 14:11
  • $\begingroup$ This short concise answer made things so much clearer for me than all the tutorials I've been watching. $\endgroup$
    – Iogictable
    Commented Nov 3, 2017 at 22:54
  • $\begingroup$ @metaphor_set I don't understand how normal map can be converted to bump map without losing information. Normal map has 24 bits per pixel and bump map has 8 bits per pixel (since bump map is black and white). Correct me please if I'm wrong. $\endgroup$ Commented Jan 11, 2021 at 19:09
  • $\begingroup$ @Cake_Seller - converting a normal map into a bump map gives you two textures, if you don't save over your normal map, that is. If you need bump maps for a niche solution, you can convert normal maps (and keep the originals) without loosing information for your niche solution. However, you are not able to convert bump maps into normal maps without loosing information. $\endgroup$ Commented Jan 12, 2021 at 7:03

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