Bump mapping help

# 1 30-09-2007 , 05:17 AM

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Hi,

just been experimenting with bump maps before starting for real. On my grey base image in photoshop, if I paint one white stripe and one black, in my renders, the white one appears sunken in, but the black one has no effect at all.

Have I got a setting wrong?

thanks,

gubar.

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# 2 30-09-2007 , 05:23 AM

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if youve got the grey set to mid greay then you need to change the colour gain to -0.5 in the file node

"No pressure, no diamonds" Thomas Carlyle

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# 3 30-09-2007 , 05:32 AM

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Hi,

do you mean the alpha gain? I've tried altering it, and the alpha offset values. It makes a difference to how the white is rendered, but the black still has no effect.

cheers,

gubar.

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# 4 30-09-2007 , 05:45 AM

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Ok, just tried it with a new scene and it is working now. Don't know why it wasn't in the previous scene.

Another question if I may - even using a fairly high resolution texture (1024 x 1024), after I blur my lines (to fade in and out of the shadow, I'm trying to do some inner chest muscles), the bumpstarts to look pixelated when I render. Are there any ways to avoid this, or are normal maps a better solution? I'm hoping there's a way to sort the bumps, since I've not looked at normal mapping yet.

thanks,

gubar.

Here's an image to show you what I mean:

Attached Images

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# 5 30-09-2007 , 11:01 PM

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No one able to advise on this bump mapping issue? Could it be that bumps are only suited to small wrinkles and creases, and not larger bumps?

thanks,

gybar

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# 6 30-09-2007 , 11:14 PM

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for something like that I would probably use a displacement map. as it looks loke your trying to get a lot out of the bump map.

I only use bumps for small/medium things, wood grain on a table top, brick textures etc etc.

A bump map alters the normal to make it look displaced where a diaplacement map actually creates geometry to give the detial.

You could try saving your map as a 2048 and give that ago to see if its any different.

"No pressure, no diamonds" Thomas Carlyle

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Bump mapping help

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