Tato Posted February 11, 2015 Share Posted February 11, 2015 When i render volume with png file format or tiff with alpha, something wrong is going in volume transparency, it doesn't show correct as in Mplay. Any suggestions? Quote Link to comment Share on other sites More sharing options...
lukeiamyourfather Posted February 11, 2015 Share Posted February 11, 2015 It's probably showing straight alpha instead of premultiplied which is what most users are accustomed to seeing. I'm guess the edges are all aliased looking and rough and the colors are too intense. Don't use PNG, TIFF, or any other image format with integer values. Use OpenEXR which is linear and floating point (and it will look right in Image Viewer). Quote Link to comment Share on other sites More sharing options...
Tato Posted February 11, 2015 Author Share Posted February 11, 2015 I have also tried OpenEXR but it was same. All the file formats had the same problem when i imported it in After effects, except JPG, but JPG doesn't have alpha Quote Link to comment Share on other sites More sharing options...
lukeiamyourfather Posted February 11, 2015 Share Posted February 11, 2015 Can you show an example of what you're getting? Maybe an example of what you expect? Quote Link to comment Share on other sites More sharing options...
Martin47 Posted February 11, 2015 Share Posted February 11, 2015 in AF, interpret the file as premultiplied, then put a "Levels" and change the channel from RGB to Alpha, then raise the Alpha gamma up to 2.2, probably this will match your Mplay image, is not the best solution but...any light on this?, Quote Link to comment Share on other sites More sharing options...
edward Posted February 12, 2015 Share Posted February 12, 2015 I think there could be two possible problems in After Effects, even after you render them as OpenEXR (current best practice) 1. Alpha channel interpretation. See for example: http://help.adobe.com/en_US/AfterEffects/9.0/WS3878526689cb91655866c1103906c6dea-7f7ea.html 2. Linear colors interpretation, See for example: http://www.3dtotal.com/index_tutorial_detailed.php?id=1552&catDisplay=1&roPos=1&page=4#.VNwdRyxJ1GY When you render from Mantra the default is pre-multiplied alpha, linear color values. Quote Link to comment Share on other sites More sharing options...
Tato Posted February 12, 2015 Author Share Posted February 12, 2015 Here are some screenshots and one png file. There is a grid on the ground and when the grid ends volume becomes transparent. I have checked those links and did the same but doesn't help Quote Link to comment Share on other sites More sharing options...
edward Posted February 14, 2015 Share Posted February 14, 2015 As mentioned previously, you should render as .exr because Mantra outputs linear color values. As soon as you output to .png, that doesn't have enough precision for linear color values. So, of course .png is not going to work. Quote Link to comment Share on other sites More sharing options...
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