ZBrushCentral

How to make a 3-D object a specific scale?

ZBrush Usage Questions
#1

OK I am loving Z Brush BUT! Since I work in the REAL world I have to model to a degree of size accuracy. I work in toys so scale is very important. I need to know how big the darn thing is. Programs that do not use a real world measurement system REALLY bum me out!

SO

If I want to make a 3-D plane an exact specific size to 4 inch x 6 inch is there a way to initialize the settings before I draw or after I draw it so it is exactly that specified size??? I know I can do this in other apps but need to know how to do this in ZB.
Also when drawing an object can you change the default pixol ratio to be a rectangle instead of a square? Say you want it to be 1024 x 1280 or ?

Can anyone tell me what the numbers represent in the scale sliders. 1 slider point = what in real world scale? Or is it just some lame number that has no meaning outside the ZB environment.

#2

ZBrush does not use scale in the conventional sense of the word. All 3D objects are by default 1 ZBrush unit in size along their longest axis. There are no units of measure that translate to other programs.

That being said, there are still things that you can make use of:

  1. All objects that are brought into ZBrush will be resized upon import based upon your Preferences settings, but will then be reverse-scaled upon export again so that they return to their original program at the same size as they’d started.

  2. You have the Transform>Info sliders at your disposal. These show a pixol value. For example, when the gyro is active in Scale mode the sliders might show values of 200, 400, 150. This means that the object is 400 pixols across on the canvas by 800 high and 300 deep. If you use a consistent value in your work of, say 100 pixols to the inch, then you’ve basically drawn an object that is 4" by 8" by 3". If you draw multiple objects with this system and then multimarker them together, the composite model will export with the relative sizes of the parts intact. You can then resize the composite model in your final software and all the parts will be exactly the size that you needed.

Bear in mind that ZBrush isn’t a CAD program. Those two approaches above are ways that you can work with the ZBrush system as opposed to fighting it. Other users may also have some ideas.

#3

Hi Bill,

I’ve sent an email to your company email address.

Chris

#4

Aurick,

Thanks for the info,

But let me ask you this. If I open and use Photoshop and measure a hypothetical value (image size) Or using the marquee selection and then see what the value is in inches would this give me what the measurement value of that specified pixel value would be. In other words lets say I have a doc in Photoshop the entire image size is 1024x1309 in pixels the inch value would be 14.222 x 18.181 in Photoshop real world print scale. Would this be the same in ZB? And could I use this as a sort of conversion method?

#5

I think the thing that you’re missing is that the system is completely arbitrary and can be modified at any time to suit your needs for the particular project you’re working on.

In other words, you can decide for one project that 100 pixols = 1 inch. For another porject you might want 50 pixols to the inch. Or 100 pixols per meter. It’s entirely up to you.

I can’t give you a hard and fast answer because there is none. Instead, I’ve attempted to share a fundamental approach that you can apply to fit your evolving needs.

#6

Aurick,

Nice explanation regarding scale within ZB!

Cheers.

#7

You might find the scripts on this grid thread useful.

Marcus