different AA threshold in one render?

V-Ray V-Ray for Maya V-Ray for Maya :: General
1

hi,
is is possible to render with 2 or more different threshold settings in one render step?
As example.
I´ve a ball swimming in water.
The ball needs more samples (1, 15, 0.01) than the water (1, 15, 0.03), but I will render it in one step.
I hope for a yes :slight_smile:
I know how to do that with render layers, but in this case I´ll avoid that procedure.
Thanks, Jörg

2

It is not possible right now, unfortunately. We’ve been keeping this on the “to do” list for a long time… You can can control the shading samples per object using the sampling multiplier in the V-Ray object properties though - I don’t know if this is helpful.

Best regards,
Vlado

3

Thanks Vlado for your fast answers :slight_smile:
I made a test with the vrayproperties attribute and found a strange thing here:
the images shows the rendering and the rendertime with and without probs enabled.
with probs disabled the render needs 2:47
with probs enabled it needs 3:55
WOW…
it´s a more or less simple plane with displace and bump and one HDRI for ref…
If the Subdivs Mult helps on the AA theme I can´t say it in this moment.
Did You mean this Subdiv Mult in your answer? For me it looks more than a Mult for GI only!?
Thanks, Jörg

vrayobjectpropertiesOff.jpg
vrayobjectpropertiesOff.jpg1277×717 237 KB

vrayobjectpropertiesOn.jpg
vrayobjectpropertiesOn.jpg1277×717 237 KB

vrayobjectpropertiesSettings.jpg
vrayobjectpropertiesSettings.jpg455×1160 75.9 KB

4

now I red you answer again and I´m sure, that I can´t find the “sampling multiplier” in Obj properties… :frowning:
“You can can control the shading samples per object using the sampling multiplier in the V-Ray object properties though”

5

It’s the “subdivs multiplier” parameter. Obviously it only works for glossy effects, GI etc, it won’t have any effect if you have clear reflections.

Best regards,
Vlado

6

hmmm..thanks Vlado…
And what do you say to the much longer rendertime, using object properties as shown below?
Thanks

7

It’s normal for the object properties to have some overhead; I’m not sure how much that would be - we should probably spend some time to profile it.

Best regards,
Vlado

8

There is a slowdown when using object properties, but it shouldn’t be that dramatic. I made a scene similar to yours and the slowdown is about 5% at most. Could you send your scene to support@chaosgroup.com with a link to this thread so we can see what’s going on?

9

thanks Mihail,
I tried to repeat the situation and couldn´t confirm what happens here a few days before.
The ca. 5% is what I see.
I will hold it in mind, and if I come again into this situation, I´ll check it again.
Cheers, Jörg

10

When you are dealing with pure reflection like that, where you only have hdr and reflection subdivs, its only the aa or the local subdivs which will make a difference.

In that case, I would suggest not to use glossy reflection since you most likely can get away with mirror like water reflection (it will speed up the render time some what) I did a shot recently with a lake with very similar setting. Only using local subdivs gave me a clean image without going too crazy into render time.