Attached Link: http://ectrr.com/Media/carraratire/

I made a tire, all nice and pretty, not I could go in and make each and ever knob on it with modeling but shouldn't it be easier to just place a bump map or displacement map over it?  I'm trying but I just can't get how to size it in Photoshop or even get it placed correctly...

anyway, any help would be cool!!

 if you want to se what I'm working with the files can be had at the above link....

I have to confess that I tend to use Hexagon for that one because I create my tyres using the full modelling process. Bump and Displacement maps work to a certain extent but never really hit the nail on the head. Sadly I have only just aquired Carrara7pro I am literally trying to learn the UV side all over again meanwhile I will have a look at the files and see if I can help you out in any way.

Quote - I have to confess that I tend to use Hexagon for that one because I create my tyres using the full modelling process. Bump and Displacement maps work to a certain extent but never really hit the nail on the head. Sadly I have only just aquired Carrara7pro I am literally trying to learn the UV side all over again meanwhile I will have a look at the files and see if I can help you out in any way.

ya, I loved Hexagon's way of working, but it doesn't work On macs at all.. very sad after I have purchased it now twice (version 1 and version 2) neither one is even workable.  I have seen that there is activity in the Hex section over at Daz so maybe after 2 years we may see some fixes!!  ya right..  :/

anyway, doesn't matter much which program, how do you create an image in Photoshop that will "fit" the item modeled?

The best way is creating a UVMap so using the generated map you can paint in Photoshop.

I just did the displacement here but didn't apply any of the color.

Mark

Quote -  Yes, you'll need to do a little UV work and shader domain work.  Create three seams, two circular ones and then a seam between them so you can unfold the entire tread using the Cylinder option. The tread area will need it's own shader domain so you can directly apply the map containing the displacement only to the tread area. 

I just did the displacement here but didn't apply any of the color.

Mark

Oh my god that is perfect!!!!

not to decipher what you stated..  
three areas/domains (each side wall and the tread area)
tread will need a seam across to take it from a donut to a flat long item use cylinder to unfold...
 apply displacement map to treads domain

should be it right?

been watching you're tut's over at VTC but even there you just used premade textures...  I think I get it now  :) sorta  :/ 

 I think you've got it!  

Quote -  I think you've got it!  

nooo... no I don't... somethings missing...  OK, i am in the vertex modeler, select the areas and created 3 shader domains (sidewall 1&2 along with a tread) after that nothing works.. I go into the UV section, add a seam across the tire, and all I get is total gibberish when I go and unfold...  so what step am I missing here...?   watched all the vids and nothing shows me ( that and the interface is totaly diff in this area between 6 & 7, but I got the gist of it)...

I didn't spend time creating 3 Shading domains, just 1: tread.  3 Would be more efficient however. In my UV map, I've created a single map with overlapping mesh - this is not a good idea for doing sidewall art. However, using the "detach mesh" option, you can do an unwrap, move the various meshes around by selecting them with their domain names, and then have a single texture map for the whole object if you like. Otherwise you may want to create multiple maps for the single object for maximum fidelity and control.

 okeeyy.. but how did you get there?

what are the 2 rings on the bottom right? the sidewalls?

 Yes. I didn't take any time to do those or get them in a circular format. I was just slicing and dicing for the tread displacement.

OK, I got the thing unwarped right... but still not getting the displacement map to apply and diff...

went inti shaders... click on the "tread" shader... apply texture map to tread...

I know I have the tiling up way to high on one of them but which one? how do I know? tried both, same crappy effect...

turned brightness way down.. 

I TOTALLY get the concept of this.. just not the way this thing goes about it....

 Hmmmm, your V setting is at 40 - it should be 1. I also suspect that you may not have subdivision enabled in the Displacement settings. You  may need to push up the sample count a little ways to begin seeing satisfactory results. (always try increasing sample count before increasing Extra Adaptive Steps)

 Now in the displacement window, engage Smooth Surface and boost your sample count to 70-80,000.

Side note: if this file is to remain in Carrara, doing it this way is a-ok - you might as well use Carrara's dynamic features to enable you to switch tire tread patterns at a moments notice. However, if this is ever to be export into another format, you'll want to definitely want to model the treads to keep polygon counts down. When this object is converted into a mesh instead of a dynamic object, it will have thousands of polygons driving up file size. 

oh and by the way  thanks  your awesome  :)

 man this brings my poor old computer to a holt too... takes for ever to keep redrawing the displacement maps

When you work on a UV map, you can choose to view only the mesh for a selected shading domain. Engage that option so you only are working with the tire tread. The mesh in the UV tool can be manipulated directly on screen to better adjust it to match texture maps. You can select multiple vertexes and polygons, or one at a time and move, scale and rotate them. 

The typical industry trick for identifying problem areas is lay a texture map into the color channel and then make sure that your UV display options are set to show texture maps. This way you can precisely align polys to map features.

Attached is the map that I use.

You're bumping into a limitation of high detail in displacement - the computer must chew on it for awhile. Another argument for modeling low poly options and then using the vertex modelers Smooth option.