Hi, sorry you mentioned you opened it in nuke,
In preferences -> viewers, what is your “disable viewer dithering” set to ?
The default is OFF (viewer dithering not disabled)
For the previously mentionned steps for introducing noise, there is a dither node for that purpose,
and you can provisionally disable the viewer dithering (affects new views in the same session) while tweaking it.
Cheers!
This is my “default” viewer config at Nuke Studio 10:
But as i said, i want to fix it at Maya or all my renders will have banding and i still dont know how to fix banding with Nuke Studio 10 either.
The next image is how i see EXR in Maya 2018 by “default”, i dont see any 16, 32 floating option, but Half Pecision is unchecked MR Haggi.
the next image, was… my original render configuration (4,2,1,1,0,0), in fact i was rendering some noise… i didn´t wanted to fight Maya 2018 about noise too, the scene is pretty big and this “low” config was already taking 10 to 13 minutes to render each frame of my HD scene (for me this was ok), raising just 1 time AA or even Diffuse, was gonna take me extra 5 to 6 minutes per frame (i tested this average time before start rendering) so i didn´t care a bit of noise in my scene, just because i was going to use “denoise” at Nuke Studio… but
after this confg produced this horrible banding i raised way higher several times, my last was AA 8 diffuse 8, specular 8 and same way i raised ray deph values… and i did this… just to test if this banding was a “raising” values problem…but after Arnold took forever (days) to render my 5 to 7 seconds raised scene, banding continued to appear; since its an animation i also used lock sampling pattern and lowered clamp values to avoid fireflies, but i already tested this unchecked, i have made a lot of testings… still havent been able to solve banding in Maya 2018.
I´m starting to think i shoud not make scenes with maya 2018 that imply raising light intensity… Arnold´s banding is just wining and for me at least it´s also a render time issue, i know for big studios 15 minutes per frame it´s nothing, Avatar 2 is taking 24 hours per frame, i mean James Cameron is going to lough about my render times or he is going to scream at me… 
LOL.
i know i didn´t aded an still of the banding, but it will be useless, i test all my animations in diferent types of display, i even test them in my cellphone some times or in several types of TV displays, I know… im picky, but i didnt saw banding when testing single renders; the banding, ramps or waves of lines are more visible clearly in animation and before rendering… as soon as light starts to increase intensity or exposure ( i tested both options), lines start to move across any flat surface, i also tested adding some noise to my flat surfaces textures, the banding is less obvious but banding is banding and i can not add noise to all my flat sufaces, my flat boxes are gonna look like leather OMG just to solve Arnold´s banding, i´m just close to give up and change the beauty of my original concepts for the sake of avoid waisting rendering time.
I hope my configurations are usefull to find why this banding occours and if so to help others with same problem.
Since a still image is not helpful, I think the only way to check what’s happening is to post a reduced scene which we can check, one light and one plane should be enough if it shows the effect.
And I agree, 4 camera samples are very low and should render quite fast. If you set the diagnostic verbosity level to “warnings + info” and show us the result, we can maybe give some hints why the rendering takes so long with these settings.
This is another scene with Arnold Area light wich also has banding in Arnold´s final render, this one didn´t required animation, so now i can show you my banding problem with Maya 2018, maybe this helps:
Same render settings,
Light:
Until now, no way to solve banding with Arnold 5.
What would help is an exr image or the scene itself. The scene itself would be most helpful.
Here is an small test scene just with a simple cube, one area light, and one material, i wish it´s just a render settings problem, if not your pc will open it with your configurations and you wont be able to reproduce the banding, i hope it does.
I tried to insert it, i think i couldn´t, how you insert scenes now? i clicked insert/upload after file uploaded says completed and i clicked “add to post”…but nothing, its just 55kbs i think it should be aable to upload this size and i don´t think i can make it smaller, already tried like 10 times, how you insert maya scenes these days to the forum?
I uploaded scene here: banding
file will auto destroy on nov 6 2017…LOL
I thinks since this is a 3d content base forum, it should have better share options and bigger limits, some times you want to share a good quality render and you cant, then renders are useless since they dont represent normal quality even if you make them small, limitas are very low.
I hope you guys can reproduce the banding in the file, because if it is other than just some render settings i think it wont work because your computers are going to load with your settings, but thats all i can do.
If some one finds a solution for banding problems, please share, so this post helps others too, wich finally is the bigger purpose of the forum.
My thoughts - are you viewing from the Arnold render view? - The default Maya render view will show banding.
If you view your render in photoshop, you’ll also notice more banding, but if you view the .exr in nuke it should display smoother.
Note: My jpeg screenshot will show banding, becasue of the compression, but if you look at my .tga version here: https://www.dropbox.com/s/6h2ycnlzk8ayxa2/banding_example_screenshot.tga?dl=0
You’ll probably find increasing the light strength or adding another light will help, in more normal scenes.
This is just an undithered 8-bit image. It’s what you’ll see if you render to 8-bit with dithering turned off (it’s enabled by default), or if you render to 16-bit or 32-bit and view it without dithering, which is what you’ll see in Photoshop if you view a 32-bit image (if you convert to 8-bit it’ll go away because Photoshop dithers on downconversion). This probably isn’t related to the OP’s issue.
But it’s hard to tell what is. It’s hard for anyone to help without being able to see the problem. If you can’t post a video showing the problem, find a way to reproduce it in a test scene that you can post.
I already posted a test scene, 1 post ago.
Nop, its not render view… it´s a final render still, my problem is banding in final renders in exr.
Nop, Nuke shows the banding exactly the same way Maya does, i already mentioned that i checked if opening in Nuke helps, but it doesn´t.
Nop, it doesn´t, more banding appears as soon as i add another light in the scene and render time also multiplies.
The dithering is nothing else but a display problem. The image itself is okay. Did you notice how the banding changes if you modify the exposure/gamma settings? This would not happen the final image contains the banding. I tried to modify the image in photoshop to increase the banding but I completly failed, so the image is okay, the banding is a display problem.
I rendered the scene, loaded the EXR in Photoshop and converted to 8-bit and there was no banding at all. DP is viewing the same thing in Nuke with no banding. You need to make an effort to figure out what you’re doing differently, and not just reply “nope nope nope nope”.
I already tested the exr in 3 diferent displays, also in my cellphone, i dont think 4 displays (2 brand new) wont work with Maya 2018 and Arnold 5… even the still i posted here has banding and other ussers already confirmed they also see the banding of the picture in their displays, its not just my displays.
I tested all output configurations, included gamma, all them show banding, the only thing that changes is the strenght of the colors, if i change to gamma workflow the colors become stronger, i generally dont use this because colors sometimes look unreal strong in gamma, but it didn´t fix my banding either, i wish it did.
i dont know if i can fix banding in Nuke the same way i would do in Photoshop, i dont even have photoshop… its not that i want to fix an still, i want to fix a complete scene with more than 250 stills and i dont think i can fix banding of 250 exr stills in photoshop, i always send my exr to Nuke, there is were i fix any other thing wrong with my animations, like noise or colors…but i have no idea how to fix Banding with Nuke.
If i modify the exposure, the scene becomes lighter with an stronger kind of light, my light is exactly the way i wanted, its not pretended to be lighter but a bit darker, because its supposed to be at night, now to fix banding i have to make my night bright as day? i dont think so, it wont work because my original scene starts dark and light intensity starts to raise in about 5 to 7 seconds, this raising is what mostly shows this horrible banding waves, If i raise light from start…then the original concept is gone for the sake of solving Arnolds banding!
I already posted a test scene 2 posts ago, the scene is called “banding” please check it, maybe you can help… just to be clear i dont want to fix a single still with banding… i want to fix 250 stills to 500 all with banding, im doing animation, and i dont have photoshop, because i dont use photoshop to post animations…
If i fix this animation it has to be in Maya, or all my work is going to have banding forever, as a last resource i might fix it in Nuke, still don´t know how.
if i can fix dithering in Maya? i dont know i will start to investigate how to change dithering in Maya, i never did that…
Here i repost the scene: Banding scene
The screenshot posted a few replies above looks quite alright to me, well inside the limits of what any other renderer would output.
Let’s see if I understand the issue…;
So, this image:
Is the SAME as this one?:
Because they both seem to be completely different. One with banding, one without. O_o
I think the problem is related to 8bit monitor. On grayscale a 8bit monitor can display 2^8 = 256 gray value. This kind of banding affecting Photoshop gradient too for example.
Can be interesting make some test on 10bit displays.