Zbrush /bridge and Keyshot import file size disaster

Hi Pixologic, hi all,

I have a problem, I wanted to render and send my work to Keyshot
over the bridge and then this is what happens.

File size change ZBrush over the Zbrush Bridge to Keyshot
Zbrush file size = 3,52 GB (3.782.262.664 Bytes)
and after saving as Keyshot .bip
the Keyshot file is increased to = 15,0 GB (16.141.920.999 Bytes) !!!

All the Zbrush subtooltiles are beautiful cleanquads, why do Keyshot change the quads in tris when importing over the Bridge and also increase the file size so much?

If Keyshot triples the file sizes that’s also difficult for the decimation master.
Any solutions, that would make me happy.


Hello @Morgaine ,

ZBrush files and Keyshot files are apples and oranges. You cannot compare them directly. They store different information, and may compress data differently. Even in ZBrush, point count is not the whole story in terms of file size.

Keyshot is supported entirely by Luxion. If you feel it is not saving data correctly, you would need to contact them.

Thank you!

Hello @Spyndel,
thanks for your quick reply,

sorry I didn’t write that down, I posted the problem in the Luxion Forum,
I also post it here because I think Pixolologic should be informed also the coumunity.

I suppose that Luxion won’t be able to help me out, because that would be a program update :wink:

I have to adapt to that and this raises some questions for Pixolologic.

The character have over 300 subtools I have to use the Declimation Master, all the subtools have uv’s and are fully textured (4096) and some are applied with Displacement maps.
In the worst case, I have to assume that I have to reduce the mesh sizes by at least 3 to 5 times to compensate the Keyshot import sizes.

Which Declimation Master settings are the best to use, so that the meshes do not suffer any damage?

After that I have to treat all the concerned subtools with Project All, do I have to pay attention to the settings with Project All?

In a later update I wanted to create the hair in FiberMesh,
does anyone know roughly how big a realistic long hairstyle would be in FiberMesh?
I don’t have the experience to appreciate that, if this becomes a very large file, I get scared of doing the work because later on I can’t render it because of the file size.

Hello @Spyndel,

the response from Luxion, unfortunately all ZBrush to KeyShot Bridge users are affected.

Luxion ticket response:

But what it boils down to is that KeyShot read geometry in triangles.

When the file is imported from Zbrush it will convert this to triangles which will in turn increase the size of the file due to more polygonal data.

KeyShot’s decision to use Triangles is based on that most other software design companies also use triangles instead of Quadrilaterals.

Unfortunately the ZBrush to KeyShot Bridge is created and maintained by Pixologic and this is would be an issue for them to decide how ZBrush files would import to KeyShot correctly.

I hope this clears things up a bit and we apologize for the inconvenience.

To show that this has nothing to do with my work,
I enlarged the original Pixologic demo head
to SDiv 7 = 14.582 Mil .ztl = 746.109 KB
saved as Keyshot .bip = 1.256.202 KB

I can only hope that the Pixologic Support can help me.

Best Regards,