Getting sharp renders in Arnold

#1

Hi.
I am having trouble getting sharp renders from Arnold in Maya. I am using Maya 2018.3. When I render anything I usually get a very blurred result. Almost looks like everything has a slight blur on it. I have tried setting the AA filter to a lower setting and upping camera samples. I have googled around a lot to find a solution but I can’t really find it.
Could someone show me a real-world example of some arch vis shots (exterior or interior) with render settings (and, even better, the whole scene)?
Thanks so much.

EDIT: I said “very” blurred. It’s not, it’s slightly blurry. But still can’t deliver this to customers=)

#2

Usually if your image is too blurry, the reason is that the the reconstruction filter is too large. The default is gaussian with a radius of 2. Try another filter with other values to get crisper results. But very often a crisper image is not well suited for animations.

#3

Thanks for your response.

I have tried different filter sizes as well as other filters. Arnold manual suggests Blackman Harris filter, and I tried that as well. No luck.

Yea, animation needs more filter but I rarely do anything but stills.

It seems to me to be a AA problem, but I have tried upping the AA samples drastically. It didnt really help.

#4

Try setting your texture filtering to off, Maya default quadratic blurs the texture too much…its a huge difference.

#5

Can you post some images to show what you mean?

#6

If it’s a texture filtering problem is here you can tweak it. with ‘closet’ and negative bias you don’t get mipmapping and as such unfiltered textures. try increase the negative bias to get crisper textures. another place for blurring is in the general render options under ‘diffuse blur’. this will be set to 0 in upcoming Arnold plugins.

#7

It sounds like some default settings is off.

Is the DoF on the camera on? Would like to see a render or a portion of the render, in case it is NDA, to see what “soft” means.

Gaussian is a softening filter though. Mitchell and Lansoz are sharpening but often make an arbitrarily sharp filter that creates lines that look aliased.

Triangle filter is the perfect compromise between Gaussian and Mitchell. It will make it crisp.

Though with Arnold there are plenty of places for settings to get wonky, I am more a Redshift/Vray person but have used Arnold on many occasions as it is used in a few of the different studios where I work.

I’d say import your whole scene into a new scene with defaul render settings. OR… start a new empty scene with Arnold as the renderer and save the render settings as “default” so you can load them into the current scene.

But if it is a texture that is soft vs the rest of the scene then it may just be that Arnold isn’t converting it to tex correctly OR you aren’t using a default setting or different setting correctly. I keep the bi-cubic default setting on the file loader default.

Here is a basic scene using triangle filter to show sharpness but not too sharp. Rest is default settings.

Triangle Filter Arnold Scene File

#8

Wow, thanks for a lot of good answers. I will try out removing the texture filtering and turning on the triangle filter on my next render.

Thanks a lot!

#9

Ok, I tried this.

Changing the AA filter to triangle produced no difference in the texture sharpness, but more of a difference in geo AA. So that’ll help.

Changing the texture filter to “closest”, on the other hand, made a huge difference. Especially in closeups. For anyone who hasn’t done this, know that your textures are BLURRY. Not slightly, but very. For anyone with the same problem, this solves it. Should I change this on displacement, bump, normal, roughness maps as well, or should they be blurrier than color maps? Also, what happens when setting the mip-map bias to negative numbers?

Thanks for all replies.

Daniel

#10

Hm, still seems a bit blurry to me.

Thoughts?

#11

the bias in the mipmap ctrls the resolution of the piramidal images. negative values determine bigger maps and so more detail and less blur when viewed from distance but generally filtering problems in animation and increased render times for very big textures. use catrom filter for overall sharper results. eventually post a scene that replicates your problem.

#12

Thanks for the clarification. If I get the time, I’ll make a scene that shows the problem. Can’t really post the problem scenes, as it’s client work.

Daniel

#13

Does mipmaping just care about distance from camera, or the overall space the texture occupies in the render?

Daniel

#14

the latter