This plane I rendered is 2x2 blender units.
The camera is set to orthogonal, size is 2, so it renders the whole plane.
The plane only has 3 faces, with middle quad set to black material, the top and bottom quads are white material, both shadeless. No texture is used.
When zooming in on the sides of the rendered image I see this:
I understand why the white to black has a bit blurriness (well not really, cause the line is perfectly horizontal, not at an angle where antialiasing is needed), but not why the edges of the black are whitened (red arrow). Why? I made an array from the texture in another program and there was a visible thin bright line on the black lines where the edges met.
How to get rid of this blurriness on the rendered image? (in Blender)
This is rendered using BI, shadeless, Ortho camera, no lights in scene, no Antialiasing. http://www.pasteall.org/pic/85981
I don’t see any of you describe.
Zooming using what?
But why must I disable antialiasing?
I need it, check this for example:
I don’t want the edges of the frame to be “antialiased” though (red marked) when I enable it, that doesn’t make any sense and I don’t know any other tool which does that.
This is for patterns which are later imported in another program (Resolume Arena) where they are tiled and animated.
Not using antialiasing the texture will look like shit, enable and edges look like shit and have visible seam when tiled.
Scale the texture in the other program and you’re wasting time on unnecessary steps.
Your example had horizontal lines only, so i disabled AA. Ofc you are not forced to switch AA off.
Again, i don’t see anything like antialiased vertical lines and you do not say what is your viewer of choice. Never heard of Resolume Arena before unfortunately however there is what i see in Gimp: http://www.pasteall.org/pic/85990
from the 1k image rendered http://www.pasteall.org/pic/85991
You can clearly see the leftmost and rightmost pixels of the black area in the very first picture I uploaded is grey, not black.
I mean this image in the first post:
I see no reason why it should be so. Lowering the render resolution makes the grey pixel edge into several grey pixels edge.
The link to the blend file for rendering this image is in my first post. Please try it out and see if on your machine it is rendered the same way and if you can find any issue there. I see the image you rendered doesn’t have this problem so something either wrong with my scene setup or my pc.
I also don’t understand why theres a grey border between the black and white areas. It’s perfectly horizontal, why is Blender “antialiasing” that part? That also affects quality.
Thanks. but this is just a simple and exaggerated example to clearly show the issue.
Thank you. I checked the description of that option and don’t really understand what you mean when you say “tiny strip of the background flashing through”. Could you please explain whats going on? That would make it easier to remember. Thanks again.
The fact that the camera does not catch the background doesn’t mean it isn’t there:
Exactly at the frame borders of the rendered image you have a transition between the plane and the light grey background, which the anti-aliasing tries to balance out. As a result a tiny strip of greyish pixels will bleed into the rendered frame.
The “Transparent” option makes the background invisible to the camera and renders it as alpha value. No greyish background visible to the camera = no need for blender to anti-alias the transition…
I understand now.
But I don’t understand how they bg is considered by Blender to not be outside of the camera view when the orthogonal camera size is set to 2 and size of the plane is also 2.
It is outside of the camera frame. But you still have a color transition right at the image border. What you see there is not the background itself, but Blender’s compensation of the color transition:
Red line = camera border. Black = plane pixels. Light grey = background pixels. Medium grey = result of the AA.
Blender by default anti-aliases “per tile” and not “per frame”, so it also takes image data next to the tile borders into account. To stop that you can either turn the background invisible (as already stated) or switch AA over to “Full Sample”:
This will force Blender to render the complete render layer first and then do the AA based on the frame and not on each individual tile.
Now at the 32x32 pixel resolution i see this gray horizontal line on both sides of black like in IkariShinji post #10 and no option except disable antialiasing makes these go but there is nothing grey on vertical sides neither if black part is simple horizontal or v shaped.
Using your posted blend file any size rendered shows value 1 on white and 0 on black on any not antialiased black or white row of pixels in UV editor (mouse left hold and drag over image in UV editor; status line shows RGB values).
Depending on antialiasing method selected there is either one or two gray lines horizontally, nothing wrong on image borders:
Edit: turns out i had left Box option on during this. Mitchel Netravali creates border lines…
Edit 2: Box or Catmull-Rom does not paint borders.
