Flickering in bump map

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Old 03 March 2013   #1
Flickering in bump map

Hi everyone,
I have a problem with an animation.
It is a sunrise on planet earth, everything is fine until I put a bump map: I get a weird flickering at the area where the light ends and the shadow begins.
I tried many things: increasing AA, shadow map, raytrace, area shadows, tweaking bias, I even disabled receive shadows on the object; the flickering persists, and when I remove the bump, it's gone.
But the problem is that I want the bump effect, so...

Does anyone has a suggestion.
Help appreciated.
Thank you.
 
Old 03 March 2013   #2
Which renderer? Did you try to change the sampling?
 
Old 03 March 2013   #3
mentalray
Yes, I did try to change aa sampling up to 4/64, it did improve the situation by reducing the flicker but it is still very visible and annoying. I'm lauching a render at night with spatial contrast set to 0.03 to see, but render times will be long : (
 
Old 03 March 2013   #4
By saying "... the area where the light ends and the shadow begins." do you mean the light and dark side of the planet?

On that case you might have changed the contrast value of the light (more than enough) to get a sharper shadow edge and that might cause artifacts in bumps.

Also consider reducing the bump map amount.

I personally don't change the spatial contrast values first. Instead, If I need to see if any sampling value helps correct a certain case, I just make min and max values equal and increase together equally.

This way you'll be setting all pixels sampled at the same rate and be sure, that value helps or not. (Probably it didn't) Sampling Diagnostics in "Processing" panel of the render settings window also might help if you know how to read.
 
Old 03 March 2013   #5
Originally Posted by Byteman3D: By saying "... the area where the light ends and the shadow begins." do you mean the light and dark side of the planet?


Yes, this is the light and dark side of the planet.
I then examined the bitmap used for the bump (it is the clouds map), and saw that it is low definition, pixelized with awful jagged pixels when you zoom on th image. It's quite big size (8k) but pretty poor quality.
An other issue is that I get horrible big jagged edge also (like big teeth).

Perharps the low quality of the bitmap is the issue.
 
Old 03 March 2013   #6
I remember hi res planet images in NASA web page. Earth, moon, day, night, clouds etc. Not allof them this high but I remember one of them being 37500 pixels horizontal. Something around 200 mbytes. and others 15000 pixels or around 7000 pixels
 
Old 03 March 2013   #7
yes, I know about these maps, but the problem is that you must, in your final product, give nasa credits because of having use their assests. It's really an issue for me as I don't like to put some ugly text over the footage, or make end closing credits in a product where it's not appropriate, etc.
 
Old 03 March 2013   #8
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