Visible Banding when using DR

[Efernando]

I've noticed some banding issues when rendering with DR.  Attached are a few images from an animation

Couple notes on my animation
- rendering exr sequence
- Lan connection/crossover cable
- pass limit 2
- Simple light setup; hdr in env slot; a couple corona lights in the headlights

I've ran the animation a few times, and the error is happening consistently.  However, I don't see the banding when I render locally on one machine.  Please help.  Thanks -Erik

[fobus]

You need to set more passes to avoid banding in DR. This is how it works, it's not a bug i think. If you render an animation and you have to use 2 passes only, turn DR off and render it without issues. DR is intended to render heavy big pictures. It's not for animation previews at all.

[Ludvik Koutny]

If you have an animation, what's the point of using DR? Just use Backburner and let each PC handle some of the individual frames.

[ihabkal]

Efernando, it is a bug I am having the same issue. Banding doesn't go away with more passes, it gets worse. Missing maps and failing nodes could ruin the process. I have 10 machines and randomly depending on the scene some work some don't. and you need to restart max or the main machine to free up ram especially when Corona crashes it doesn't free up ram properly.
The banding I get is exactly like yours it is a bug since it happens only with max 2016 and corona. same scene renders fine with max 2015 and corona. We need to wait a little So Ondra can fix this. Ondra please pay special attention for DR becuase professionally you can't render at 5000 or 10000 pixels wide without 10 machines helping clients won't wait a week for a rendering to be calculated. Proper DR is the only way to do high resolution renderings in a timely manner!

[maru]

Guys, have you already seen this?
https://coronarenderer.freshdesk.com/support/solutions/articles/5000501666
Especially check out points 2 and 3 under troubleshooting and the "should you encounter..." advice at the very bottom. Sorry if you have already tried these solutions.
Also, please update DrServer (the link is in that article too). Corona 1.1 is coming soon, it should have many DR fixes.

[ihabkal]

I just installed the released 1.1 on max2016 and tried DR with a node and it works great just make sure not to use vray HDRI and use corona bitmap instead or make sure if you are using vray hdri that all nodes have the latest version. Will try with all my nodes tomorrow:)

[Efernando]

Thanks for all the help guys! 

@fobus; you are totally correct.  using DR required me to give each frame a bit more time, so that the slave can catch up; 2 samples was not enough.  I raised the pass limit to a minimun of 8.  What also helped was lowering the "synchronization interval" in the Distributed Rendering tab; previously it was at 60.  My guess is that the slave was too far behind in the passes, so when they got merged together when the frame finished..it only had one pass finished.

@Rawalanche; Yah, I hear ya on that.  I just setup backburner and I'll look into that more for animations. 

@ihabkal & maru; Thanks guys, I'll make sure that I'm on the most current 1.1 release to get rid of any exsisting issues.  One important note I saw in the troubleshooting is to make sure that all slaves have the same max gamma settings.  Very useful info

Again, appreciate the help! -Erik