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Bump map values?
Posted: Tue Jan 15, 2013 3:07 am
by ASyme1
OK, seriously. I've had most of my shop looking into this and can't figure it out. When I assign a bump map to a texture it defaults to a value of .9 out of a value range o 0-1. So, right off the bat we're essentially at 90% of the maximum range for a bump. There's no over cranking this. What? That's ridiculous. I over crank bump values all the time.
Can someone please tell me how to get a more usable bump map value out of Octane? I MUST be overlooking something. This is big.
Thanks much! Help!!
Alec
Re: Bump map values?
Posted: Tue Jan 15, 2013 4:55 am
by face_off
From my limited understanding of this - yes, there is a limit to how "bumpy" a bump map will make a mesh look. You can increase the bump effect somewhat by reducing roughness and increasing specular and adjusting index accordingly. If you have a truely "bumpy" surface, it probably needs to be modeled as such with polygons (ie. use ZB to convert geometry + bump map into high density mesh).
Re: Bump map values?
Posted: Tue Jan 15, 2013 1:41 pm
by kavorka
not an ideal solution, but try taking the bump into Photoshop and adjusting your dark and light curves to get more contrast/make your darks darker and whites whiter so they have more of an effect.
Re: Bump map values?
Posted: Wed Jan 16, 2013 3:55 am
by ASyme1
face_off wrote:From my limited understanding of this - yes, there is a limit to how "bumpy" a bump map will make a mesh look. You can increase the bump effect somewhat by reducing roughness and increasing specular and adjusting index accordingly. If you have a truely "bumpy" surface, it probably needs to be modeled as such with polygons (ie. use ZB to convert geometry + bump map into high density mesh).
Sorry but this is not an acceptable workaround for decent bump maps. Just build it in geometry? That's retarded. I've been doing this for twenty years and I know the purpose of bump maps is to NOT have to model them. The purpose is in fact the exact opposite of modeling it.
This needs a fix, like sort of now.
Alec
Re: Bump map values?
Posted: Wed Jan 16, 2013 4:00 am
by FooZe
Hi Alec,
Try turning down the gamma for the bump texture, or running it through a color correction node. It could be that your particular map does not have enough contrast. What kind of lighting do you have as well? Bump/normal maps don't respond well to uniform lighting (ie directional lighting across the surface will show more detail than a light pointing straight at it, or a uniform environment map).
Perhaps some screenshots could help here?
Thanks
Chris.
Re: Bump map values?
Posted: Wed Jan 16, 2013 4:35 am
by ASyme1
FooZe wrote:Hi Alec,
Try turning down the gamma for the bump texture, or running it through a color correction node. It could be that your particular map does not have enough contrast. What kind of lighting do you have as well? Bump/normal maps don't respond well to uniform lighting (ie directional lighting across the surface will show more detail than a light pointing straight at it, or a uniform environment map).
Perhaps some screenshots could help here?
Thanks
Chris.
Thanks for trying to help FooZe. I appreciate it. It's not so much I need to change my lighting, of boost the contrast of the bump map. The problem is Octane just doesn't do much with bump or normal data. I can hardly tell I'm even using a bump. As would be the case if .9 is nothing and 1.0 is the max. Why is is the the range for the map? It's almost nothing. Do you not see this?
I would love to be shown I'm dumb and don't get it, and that it user error. That would be sweet.
In every other piece of software I've ever used, cranking a bump map really effects the look of the texture. In Octane, it's almost invisible.
Why? Thoughts?
Thanks-
Alec
Re: Bump map values?
Posted: Wed Jan 16, 2013 4:53 am
by roeland
What kind of scene are you rendering? Does it have the correct scale? Can you post a screenshot?
--
Roeland
Re: Bump map values?
Posted: Wed Jan 16, 2013 4:54 am
by face_off
This is a 1 min test of bump and it looks OK to me - it's a turbulence node and it's very pronounced. Are you looking for a stronger effect than this?
Re: Bump map values?
Posted: Wed Jan 16, 2013 5:00 am
by r-username
I have to agree and almost never use image bump maps, even with 100% black and 100% white areas.
Depending on the type of bump needed you can plug a turbulence texture generator into the bump node and it works quite well and can be quite rough.
The other texture generators work too depending on the type of bump needed.
Re: Bump map values?
Posted: Wed Jan 16, 2013 5:11 am
by ASyme1
r-username wrote:I have to agree and almost never use image bump maps, even with 100% black and 100% white areas.
Depending on the type of bump needed you can plug a turbulence texture generator into the bump node and it works quite well and can be quite rough.
The other texture generators work too depending on the type of bump needed.
Well, I use image maps almost exclusively. So these generators don't do anything for me. Think of a simple jpeg wood texture map. I'll need to bring in a corresponding greyscale version of it. This is the issue. That greyscale image does almost nothing currently.
I do this all the time. Is there a work a around?
Thanks guys
Alec