I’ve made a simple demonstration movie to show what happens if you “glace” colors using polypaint on a LAYER. This issue makes the concept of polypainting on layers useless.
No blending modes are used.
This time I used the hpolish brush to paint and I really like the feeling this brush has when painting but the appearance of the hard edge from the previous color is …
Luke
Check your brush menus, under Samples there is a setting called Preserve Edges, with the Hpolish brush I believe this is active.
Try sliding it to 1 then repeat the method, it may work, it may not but it’s something to try.
Thanks man, but this happens with all the brushes that I’ve tried 
Ah that sucks. I tried polypainting across layers for the first time today and it all worked fine, I’m not having that issue so hopefully someone comes along that can fix it for ya.
Someone else posted something similar to this, and I mentioned that I couldn’t reproduce it. This time, with the video, I can say that it is in fact extremely easy to reproduce! I had originally tried one color per layer perhaps.
Definitely a problem. I hope this gets fixed.
It looks to me like there’s a ‘matte’ color problem similar to the problem web designers see with transparent gifs. In gifs, there’s no actual alpha channel, it only has a transparency on/off bit. For partially transparent, soft edges, the transparency is treated as a matte color, so transparent parts only look right over top of colors that are close to the matte.
In ZB, there might actually be an alpha channel, but it is treated strangely when painting versus layer compositing.
When you paint with a color over a layer area that has never been painted, the areas that are nearly transparent are set to the brush color with a transparent percentage. When you paint with another color – the larger the difference, the more noticeable the result – the parts that are fully transparent modulate the new color in a different way than the ‘tinted’ transparent places. It looks like perhaps the transparency percentage itself is perhaps modulated in an unexpected and undesirable way.
In the meantime, there seems to be a couple workarounds:
paint different colors on different layers, then merge down. the method used for the compositing of layers works correctly, so the colors won’t have those ugly halos. (of course, because the way the layer stack grows DOWN on the screen, the ‘merge Down’ button should be ‘merge UP’, because that’s how you view the layers. sigh) Note that the halos come back if the paint layers you’re merging do not have 100% intensity! grr.
This method probably best if you stick to one color for a long time, don’t have many overlapping colors, or there isn’t any transparency in the layer.
‘Prime the Matte’. Turns out that when you erase the paint on a layer with the alt key, the function doesn’t erase the paint, it just sets everything to 100% transparency with the normal paint tint. So if you paint a blob, then erase it, then paint a low-opacity different color, you’ll still see the ‘stain’ from the first color.
If you’re planning ahead, this can be used to your advantage. First, set your rgb intensity to 100, then hover over an average color on your model and hit C to copy the color. Scale your model down and crank your brush size up. Paint that color over the entire model. Immediately hold alt and erase over your entire model. The layer looks to be doing nothing to the model, but you can now paint in multiple colors and they’ll blend like you’d expect.
Border erase. When you see the color stain ring effect, you can erase with low opacity along the border, and then re-paint over the area. This seems to allow blending of the colors in some cases, although I’m not sure how practical this might be.
Long story short, this behavior is ungood – not at all how polypainting layers should work. Please fix pix
Edit:
ExtraDimensional : did you try painting overlapping, different low-RGB intensity colors in the same layer? The layer compositing works (mostly) ok, its just within a layer there’s weird stuff happening.
Yeah I tested over multiple layers and it works fine, but when I tested just now on a single layer I got the halo nastiness as well. Here:
[
](javascript:zb_insimg(‘210238’,‘colorerror.jpg’,1,0))
The stroke painted on a seperate layer has a nice gradient blend, the low intensity stroke painted over a previous color on the same layer has the harsh halo, so yeah. Bad juju there.
It’s going to be Workaround time for now until it’s smoothed out in an update or something.
MODERATOR…please delet this post …Thanks
Thanks guys for taking the time to reproduce this issue. 
yeah I forgot to mention that I’m painting on one and the same layer.
at least I know now that there’s nothing wrong with my settings/pc/whatever.
Cheers