Update: Ok the result is still the same. So i am unsure if the issue is my texture itself. I have no issues using diffuse but glossy bump gives the above.
Huh. It’s not just that it’s pixelly-- it looks like it’s bumping areas that shouldn’t be bumped.
I wonder if some kind of dithering in the image editor you used for the blur could be responsible.
The first thing I’d do is try to use the full range for the bump map-- just auto-levels in most image editing software should take care of that. That would make any artifacts in the image more apparent.
Then I’d be making a dummy material using it as an emission shader to look for any issues with uv, uv interpolation (sphere’s a hard thing to map). And of course just to rule out everything that’s not the bump map.
If you’d like, I just made an in-material node for a 5x5 convolve (incl. gaussian blur) at https://www.blendswap.com/blends/view/90979 . You could use that to run a gaussian or box blur inside the material instead of on the image and see how it affected things.
Have a look at this post. It’s synaglo0w’s procedural hexagons (and a heck of a lot more useful tiles) with a whole heap of useful outputs although I typically only utilize a few of them. One output that is missing is distance, but you can obtain that going "Tile Space - > Gradient Texture/Spherical). That is useful if you want a center bulge that is not shaped as a star which the top Gradient will give you. For bulge control you should use a spline color ramp (or a custom Smoothstep/Smootherstep function if you have it - I prefer this over color ramp).
Textured bumpmaps works best when they are small enough to hide the difference between each pixel value. For continuous gradients like this I much prefer procedurals to avoid those problems. Using normal map instead may be beneficial in this case.
if you are using a JPG!!! image as a height map then THERE WILL be issues
and you will still have those same problems if you try to convert a 8 bit jpg to 16 bit tiff
– that dose not work !!!
use the procedural hex above
or
make a real 32 bit float hex grid
– !!! without the jpg compression artifacts !!!
here is a shaded gray image using the image you posted