I can’t create usable alpha from mask which I have create using mask by cavity.
Alpha mask is attached. It just has a lot of speckles around where a mask should be.
See recording of a problem here:
http://www.borisgoreta.com/forum/maskexport.mov
Having the exact same issue here (Exported maps look very similar to yours as well).
Yes, I have mentioned this problem aswell.
The only solution I have found is to open the file in Zbrush 4 & create the maps there.
I confirm this issue.
But how, ZBrush 4 won’t load tools or files ( .ZTL .ZPR ) saved from 4R2 .
Yes, your quite right.
Just export you model in OBJ format (whilst in ZBrush 4R2), then import into ZBrush 4, then create your maps. Yes, it’s a pain in the neck, but at the moment I cannot find another alternative.
Unless, someone else can shed some light on how to get a result?
Ok thanks, is there an official way to file a bug or is this it ?
We’ll log any confirmed bugs reported on the forum, thanks. 
Ugh…This is such an annoying bug. I hope they they can get this fixed.
waaaahhhhh :(. My favorite thing is borked. I shall sit here patiently staring at the screen until it works again. Thank you in advance for fixing it.
There’s also another way to do it. If you have any polypainting on your model, erase it by filling with white. Then, you could generate the AO/cav mask as usual, invert it, fill the (now masked) object with black color, and just use new from polypainting. I’ve tried that and it worked perfectly well.
Quite less painful than exporting back to Z4, innit? 
Thx that workaround works… now a real fix would be nice!
Thanks a lot for the solution. This will save me a lot of time once I learn how to fill an object with black color after I’ve masked it ? :rolleyes:
@Boris Goreta - In the upper left corner of ZB interface, there’s the Color dropdown; open it, and press FillObject. It will fill the entire model (with respect to masking) with the currently selected color.
That does take a lot of pain out of getting the maps, thanks!
thank you so much for the temp solution man i was just freaking out
Inverting the alphamasks technique works! Thank u so much!
i get the feeling it has something to do with the create alpha from mask feature not reading the UVs. anyhow i found the same work around as already mentioned. just mask the model as desired, then fill the unmasked parts with a color, then make a new texture by clicking on “new from polypaint”, click clone texture, then from the texture menu up top select “make alpha”. after the alpha is created you can invert if needed.