arnaud giret

arnold_FR

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Recent Forum Posts

Converting textures to ACEScg Aug. 24, 2019, 9:21 a.m.

Hello,
thanks for this post,
i've made my testings on my side,

In the case of an 8 bit srgb image file
in the file node in cop check linearise non linear images,
this will make your 8bit a 16bit / then do a vopcop2filter
> Utility - Linear - sRGB conversion to ACES - ACEScg : just as previously mentioned.

If you don't linearise what happens is that your 8bit stays 8bit,
so for example if you try to put a gamma correct node after the conversion,
colors will be clamped and saturation will touch the sky > not be relevant anymore.
(That's what may happen if an intense light is close to this texture).

If you don't want to linearise, put your file node then a convert node
to convert 16 bit then apply the conversion to acescg as previously mentioned.
( Or make your own by down “fstopping” + up ‘fstopping" the duplicated file manually
and then do a fusion hdr in photoshop, that may help to fake the 16-32 bit look
with an 8bit file but that’s out of topic).

Hope it helps,
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Mantra : Per object sampling + resolving cyc grainy problem July 25, 2019, 8:09 a.m.

Wookay,
My bad did a search on videos where i've got all i need in the pdfs from the user guide here at :
https://www.sidefx.com/tutorials/mantra-user-guide/ [www.sidefx.com]
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Mantra : Per object sampling + resolving cyc grainy problem July 24, 2019, 4:51 p.m.

Hello,

I have rendered a Mantra scene where i felt i had to push samples higher than needed,
but first here ‘s the render / it’s a test for volume with vel added from a solid and particles.
Image Not Found


Ok,

My problem was that i had to cranck up the samples on the entire scene just for the cyclorama to look noisefree,
and i would like to know how to resolve this the more efficient way possible.
i think possibly (but there might be other ways)
By :

a ) Upsampling on a per object basis : the cyc only : but i don't know how to have a per object samples override ?
i'd like to have a control over diff, refl, quality.
Is it done in object param : left clic : Edit Rendering Parameter / MANTRA ?
If so, the list is long, so how to know more about using those features ? (just did not read enough infos in the doc about that)

b ) by telling this object to receive only a less computational GI algo may be ?
like only primary rays or something ?

am i thinking correctly ?
what would be the process to optimise rendertime
when you have a large surface of your image that need a lot computation but don't add much to the final look ?
(appart from making it only diffuse or no blurry reflection).

> thank you !

and if i may ask : we need another masterclass about Mantra, i've just been watching everything from 2015 today,
and i'm still starving, may be forget about the 1h30 limit and give us something really big ! that would be awesome.
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