Rndrs : need help against grain

[dotcom]

Hello everyone,


Please have a look at my renders,
i've rendered those out with a gt740M GC with 4G Ram.
THese are direct renders from octane, no post.

As you can see there's a sort of a photoshop filter applied to the image,
and after 30 mn render, still the result is not that convincing to me.
I'm looking for a realistic grainless pic.







I think i guess after 30 mn rendering it should be possible
to have a render that would be abble to be shown to a customer.
Even thought those are for testing purpose.


Here are the some screenshots of the settings :
octane render,
hdri 4096/2048.
4 lights around the object
big cylinder as a scene + floor.




Please, help me out with this, if something seems weird to you.




I'm wondering too what phase of the calculation is when
suddenly some new sequence of the image render happens :
there's a first phase where the scene is in the dark
then octane seems taking more samples area,
the scene is brigther, but grains are on top,
then image is defined deeper, grain disappear a little/
and there's a new phase coming up : grains on top, then gets deeper again/
and so it continues phases after phases.
Is there a relationship between the number of those phases and the "maxdepth"
setting in octane render settings ?


I thanks you very much for any of your help,


Have a good one,
cheers,



Arnaud.

[djart]

Hi dotcom,

maybe you give the Car Environment Setup i attached a try. The image is rendered with this setup with one single GTX 680/ 4GB for testing purpose.
I dont know how to compare it to your 740M, but it took approx 5 minutes to get the result you see here.

For faster renderings you can switch from DL diffuse to AO, it will render much faster.
If you change the HDRI, you will need to tweak some materials.
To get even faster results, you can use a denoiser like neatvideo or else to get rid of small grain that appears on glas sometimes.

cheers, djart

[aoktar]

well,
your the render seems like corrupted images. Can you render some other scenes as well?
Try At least a few object with daylight and other try for a hdr environment.

[dotcom]

Hello,

Thanks a lot for your replies,

Thanks for the scene reference Djart and nice to you to share it
really i appreciate this.

Thanks Aoktar,
Yes renders seems really really longuer as an hdri gets int the scene,
i've already made trying daylight but hdri is the only where rendertimes jump to sky
and no matter what i still got too much grain, to use it in production,
i let the image for rendering during 31 hours and still i had grain :
this was a 4048 px picture for 4k tryouts.

Aoktar, i'm a bit confused with the term : "corrupted image" what does that mean ?


cheers,
thanks !

++

Arnaud.

[dotcom]

Here are some tests down inside the scene of Djart,

First two ones are done with my hdri,
the third one with the hdri of Djart.

The more complex the hdri, the more grainy ...








Please don't tell me i have to work with simple hdriz,
cuz my point is to use real hdri shots with octane...


Cheers,

[aoktar]

i think is problem on your gamma or quality? are you sure it`s a hdr or exr? als9 did you checked importance sampling?

[NVN]

yes...look at your picture.
U forgot to aktivted importance sampling.
I think, thats the point.

[aoktar]

yes, checked sshots's again one is importance sampling. HDR image is very important for good images.
A note: 740 should be very slow against a 580 or 780 as least 3-4 times