Cryptomatte render not extracting as expected in After Effects

[maja.divjakW2VMQ]

Hi there,

I'm trying to render a cryptomatte layer in Maya 2019.3.1 using Arnold 4.2.3 and Arnold core 6.2.1.1. I'm outputting .exr files using the crypto_obj AOV and have tried merging AOVs and not merging the AOVs in the render. I'm rendering using 'render sequence'. The merged files are large ie 154MB and the unmerged are 121.5MB, suggesting the cryptomatte info is in there. When I bring into After effects and apply the cryptomatte effect, I do not see all my objects displayed as a range of flat colours, as expected. Some are white, some black with white outlines, some only outlined and one is bright blue. Please see attached image. Also attached is my beauty pass for reference. I haven't disabled my lights as I believe this is unnecessary for crypto rendering? Has anyone seen this before or know what I'm doing wrong please? Could the plugin be a problem? This used to work for me and now does not. Any help greatly appreciated.

Thanks so much and best wishes,

Maja

[Stephen.Blair]

> I do not see all my objects displayed as a range of flat colours

That sounds like the Preview in EXR feature. Cryptomatte doesn't need those colors to work, it's just for preview.

[maja.divjakW2VMQ]

Thanks Stephen, where/what is the 'Preview in exr feature'? Is this in After effects somewhere? It would be great to turn on the view that I'm used to, as it is very difficult to make selections from the images as they currently appear. You can make selections from some of the objects, but many of the crusty outlined objects are not selectable, as they are not complete outlines and you end up selecting the background. Many of the black objects are also not selectable. Conversely, the white and coloured objects won't readily deselect. So, I'm still not certain this cryptomatte render is working as it should. If you could please advise, that would be great.

Thanks so much,

Maja

[Stephen.Blair]

Preview in Exr is a Cryptomatte option in MtoA

[maja.divjakW2VMQ]

Hi Stephen,

I tried re-rendering a couple of frames with 'preview in exr' checked off, as you suggested and this made no difference. I'm still seeing the crusty outlines, black shapes, white shapes and one bright blue shape, which do not behave well in AE ie they cannot be selected or deselected, as desired, to create mattes. This is a rendering issue as I have some previously rendered cryptomattes that do behave in AE, so it is not AE or FNord cryptomatte plugin related. If you could please advise how to render cryptomattes properly, that would be great. I'm sure some check box has become turned off somewhere, but I don't know where to begin trying to find this. Would you recommend reinstalling or updating Arnold?

Thanks so much and best wishes,

Maja

[maja.divjakW2VMQ]

Hi @StephenBlair,

I have set up a simple file with some coloured shapes from which I have rendered the cryptomatte. Bringing into AE gives the same result ie shapes with crusty outlines that can't be selected and one black object that can be selected. Please see attached image. I have also tried to attach this maya file here to see if you get the same results please? However, it won't let me attach either .mb or a .ma file

Thanks so much and best wishes,

Maja

[maja.divjakW2VMQ]

Hi Stephen,

I've discovered that if I set my Colour Management 'View transform' to RAW and in the render settings window, set the color space to 'Use View Transform', then the image will render correctly in the render view window and the cryptomatte info can be correctly extracted in After Effects. The problem now is that I cannot render a sequence of images using 'render sequence'. The render constantly aborts or crashes the file. If you could please help, I would very much appreciate it. Interestingly, it sometimes works and sometimes doesn't. Attached are Arnold logs for the render view and render sequence. I hope they reveal the problem

Thanks so much and best wishes,

Maja

arnold.1129RenderView.txt

arnold.1133RenderSequence.txt

[maja.divjakW2VMQ]

Hi again,

I've just managed to fire off a render sequence successfully. An Arnold log is attached. Hope it reveals something to you.

Thanks so much,

Maja

arnold.1142SuccessfulRenderSequence.txt