Problem rendering in pathtracing mode

Omniverse Apps USD Composer (Create)
1

Fisrt I was having this problem exporting images , then I find what i think is a bug , because Machinima doesnt but CREATE does , both with the same file .

First i posted this on the discord channel :

I dont get very clear the "Total samples per pixel " in path tracing mode , i mean this is only for real time path tracing? when i export with movie render i dont understand very clear if "Path trace samples per pixel (per subframe ) " is the same thing , or if they are two independent settings one for real time and the second for export movie , for example “160 total samples per pixel” i have very low resolution images in comparision with the viewport render , why the viewport lokks fine ? i mean , why viewport look ok at 64 samples per pixel and exported image is noisy ?

After several hours testing I have this results :

i am having lots of error messages , and suddenly it stops rendering in pathtraing mode , just a gray screen in viewport and cero files created , as soon as i switch to realtime rtx it renders ok but still this error messages .

EDIT well… after running some tests on this issue i have found a few things :
1- Movie capture present this issue off no rendirng at all as as soon as i cancel some export process while using path tracer, it comes back to normal if i restart the program . in RTX realtime it works as expected .

2 The issue happenns in CREATE ( i thought it was version 2021.3.3 but i uninstalled it and tried again with version 2021.3.2 ans i have the same problem ) in MACHINIMA it works ok! BUT . i cant control the movie export resolution from render settings menu. I need to set "Path trace samples per pixel (per subframe) " to at least "5 " in order to get a noiseless export PNG , for now it would be a workaraound for me . my GPU is a RTX 3060

windows 10 ryzen 2600x 32GB ram GTX 1050ti RTX 3060 Aourus b450mcreate logs.zip (498.8 KB)

salon2.0001
salon2.00011920Ă—1080 342 KB

unknown
unknown1878Ă—940 99.2 KB

error

NOTE . "samples per pixel for iteration " was alwas set to 1 in all tests , i made the screen capture the only time i tried different settings in that field , thats why isat 64 in the capture

thanks in advance.

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Hello @poyodiaz. Thanks for your questions. I informed the Rendering team to take a look at this post.

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Hi @poyodiaz , for “Path trace samples per pixel (per subframe)”, it’s not the same to “Total samples per pixel”. To get the totals samples it will need to multiply the number of subframes, which you also can set on the Movie Capture UI.

Also, the result images’ resolution should not be related to path trace sample per pixel settings. Instead, it should be the same to what you set in the Movie Capture UI. If not, then it’s a bug we never heard before. So could you please try if you can reproduce this in the latest Create? Thank you!

And for your findings in “1- Movie capture present this issue off no rendirng at all as as soon as i cancel some export process while using path tracer”, I’m afraid I don’t quite understand what does the “some export process” mean. Could you please elaborate? Thanks!

And yes it’s true that to get images with better quality, you will need a higher total samples per pixel. I don’t have Machinima installed for now but indeed Create and Machinima should behave the same.

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Hi , well i think i finally understand how movie capture behaves , (i am turning off motion blur for now), but still have the problem when cancelling a render in the middle of the process , if i cancel , the render engine seems to break and wont work until i restart the program , not happening in machinnima , i dont know either what the error messages mean , it just begins to throw them after cancelling the render before it ends .

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hello @poyodiaz -
Can you share with me all your movie rendering options that you have selected for the case where stopping the move results in needing a restart? screen shot of the pane would be ok

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Hello, I am beginnig to suspect that this error was a combination of my poor understanding on the program natural behaviour (maybe my gray screen was the program progress to skip already rendererd frames ) and some random problem with this file, i was trying to replicate the problem and is gone now ill keep trying to track the issue and if it is the case il share more detail info .

1 Like