How do you Bump ?

3DAGE

I'd like to get some general feedback about how people are using the Bump in Carrara,.
even if it's not the right way,.. I'd like you to tell us how you adjust the bump value in carrara.

:)

Design Acrobat

I prefer normal maps over bump maps.

However, when I do use bumps I either use:

(1)The color map and these use the black and white function in Photoshop to get the elevations as correct as possible.

(2)Use Xara Xtreme or some incarnation of and its bump map function to make a bump map.

3DAGE

Thanks Design Acrobat :)

It's been a while since I head it called Xara Xtreme :) ..Now designer pro ... I preferred extreme :)

Anyway,.. I'm going to rephrase the question.... it's possible confusing.

Q: How do you adjust the Bump inside the Carrara shader tree ? ,.

EG: do you adjust the brightness of the Bump map,. ...or,. adjust the Top level option for bump.

Garstor

I'd have to say, a bit of both. I usually use the colour texture map without changing it to black & white (laziness I guess). But the top level is the easiest spot to adjust the bump percentage value.

Design Acrobat

Ah well, I misunderstood the question. I'm like that old mule, you have to whack it in the head with a two by four piece of lumber to get its attention. :)

I generally use a mixer in the shader tree. A combination of color gradient from black to white (with a gray center).

I use the value (1-100) to set the desired percentage)

And adjust the amplitude last for minor tweaking.

The two images show height map changes using "spots" from Carrara. The last image is the settings with the setting showing the inverted (sunken depth) settings (first sphere image shown). (tweak the amplitude for elevation settings i.e. negative amplitude elevates the bump and makes the center more light when using grayscale gradients)

note: use the blending function in "spots" to get a similar look that I achieved for the shape of the spots and frequency.

Design Acrobat

Same technique as above, but using a texture map where the shader "spots" is.

In this case I used a Mayang Website map called "mosaic" tiles instead of "spots" and lowered the amplitude to get the effect.

3DAGE

Thanks guy's :)

Garstor,. no worries about using the colour map in the bump channel,.
Carrara is smart enough to know that only grey-scale should be there. so it desaturates the colour map automatically.

Design acrobat,. Nice.

Yes a mixer can often give you more control over the bump, since you can adjust the values of the two sources ... B / W

So,. I'm glad to see you're both using the main Bump amplitude in the top shader,.

Its just that I've read some stuff recently where people were using the Brightness slider for the Bump image map to control bump.
rather than the actual Bump value.

technically that's wrong,. but it will obviously change the bump strength,. but what's happening when you do that, is that the image is getting darker, until it's black. so you gradually loose the high values.

I was interested to find out how many people are adjusting the map, and possibly don't realise that there's a Bump control.
since it's in the top level, and not entirely obvious when you're looking at the Bump channel.

Garstor

Yay! I did something right! Mark the calendar! :lol:

TangoAlpha

So far all I've done is make a greyscale of the colour map, and tweak the brightness/contrast in Photoshop to make the map less noisy. I wasn't aware of the adjustment settings, & will have a play when I get home tonight.

Normal maps - they're the blue ones, right? Not sure why I might prefer one over a bump map, but I don't think I can make them anyway - as I understand it, they need a plugin to generate them, and I only have baby Photoshop, which doesn't support plugins.

3DAGE

HI Tim A :)

You should check out Filter Forge.

http://www.filterforge.com/

It's a Photoshop plug-in to make your own image filters, but,.. there's also a stand alone version. (both in one download)

Normal maps are usually Blue and Red,. they provide more detail than a grey-scale bump map.

quick example:

evilproducer

If it's an image map, I'll generally do it the "wrong" way sometimes and adjust the slider under the thumbnail. I understand what it does in relation to the image map, but if it gives me the result I want, then I don't consider it wrong.

I do use mixers and multipliers on occasion as well for image maps.

Garstor

3DAGE said:

You should check out Filter Forge.

http://www.filterforge.com/

It's a Photoshop plug-in to make your own image filters, but,.. there's also a stand alone version. (both in one download)

Normal maps are usually Blue and Red,. they provide more detail than a grey-scale bump map.

Agreed! It is awesome. I just upgraded to version 4 today as a matter of fact.

I gotta confess though, I have not figured out how to make normal maps with it. :red:

Dartanbeck

I crank on the top level slider. Of course, I make a whole bunch of bump maps, sometimes I'll blend two or more together... but not often. I don't really ever lower the brightness of the bump map unless the highs and lows are too drastic at the level of bump I need.

Terrain shaders have been really fun in this. You can crank the bump up to 250%, but you can enter in values up to 500%. Any higher jumps down to 500%. But with the right bump map, I've been able to make leaves appear as if their laying 'above' the surface, like they do when they're dry. I like using bump.

I have noticed that we have to be aware of bump levels vs rendering quality. Too low of object/shadow accuracy can make high bump values look fuzzy or worse. Tweak these setting, however, and we can make really great use of bump without the need for displacement, which can take a lot longer in the rendering department.

wetcircuit

I use Veloute Tools Filter (plugin) on image maps. It puts the bump on steroids, and also has controls to crush/stretch the whites and blacks (like a Levels control). I use it most for fixing/limiting specularity maps which can be any random range of greyscale, but in the bump channel it turns maps into super-bumps (not an actual technical term) that extend beyond what usually a B&W image can create in Carrara (not that it's always a good idea because it can stretch way past what looks good into some weird and ugly territory).... It also works to stretch/limit Carrara's procedural shaders.

Just checked Inagoni's website. He calls it "rich bumping"...

Dartanbeck

Most impressive. ...and Rich!

3DAGE

Evil producer :)

doing it the wrong way still works,. and whatever works ...works,.. in a way.
it's just that the Bump amplitude will allow you adjust the Bump effect, rather than adjust the map brightness,..

Holly :)

that does look rich :)

Garstor :)

In Filter forge, when you create a filter, change the setting from a filter, to a surface,.
then whatever feeds into the Height channel,. can be rendered as either a Grey-scale Bump map, or a Normal map,..
just select the render map options from the filter menu (Pic)

Dartanbeck :)

Good info,. and again, mixers can be a lot of fun :)

Garstor

3DAGE said:

In Filter forge, when you create a filter, change the setting from a filter, to a surface,.
then whatever feeds into the Height channel,. can be rendered as either a Grey-scale Bump map, or a Normal map,..
just select the render map options from the filter menu (Pic)

Thanks Andy! Once again...I'm not exploring deeply enough! :red: