Rendering blowout or exposure issue, rendering freezing - DBR

[chrishuntsman]

So I am relatively new to 3DS max and rendering in Mental Ray. Tonight I am getting an issue I don't really understand. I am getting this really bright spot (over exposed?) in my image, don't have any lights in that location. Maybe someone in this forum knows exactly what it is?

 

Also, every time I cancel the test rendering 3DS max freezes. It also freezes at the end of the rendering when its complete. I am using DBR, which might be the issue, but I hope not. I understand backburner might resolve this issue but I would really prefer to use DBR if possible (I really like seeing the progress on my screen)

 

I have tried googling and searching for an answer so sorry if this issue has already been addressed many times, I am sure I am not using the right keywords when searching for an answer. Try typing in 'rendering issue' and see how many results you get .

I have also looked through the light lister to make sure there isn't a rouge light chilling out right there.

 

Any help would be greatly appreciated.

 

[chrishuntsman]

well I turned off the sky portion of the daylight system and now the bright spot is gone. I also disabled DBR and then tried canceling the rendering, which didn't freeze the rendering. so it looks like DBR is causing my rendering progress to hang up at 100%, won't do the clean up. Anyone know how to resolve that so I can still use DBR?

[chrishuntsman]

Thanks for the suggestion. It will render to 100% and never proceed to clean up, but I am still able to save out the image. So all is not lost, but its still frustrating. I have even tried cycling through each render slave to see if one in particular was hanging it up. This didn't conclude anything since I kept getting different results. I guess I better settle for backburner. On the plus side it will let me use more then 4 render slaves.

 

I will try rendering it as a 2 framed animation and see what happens.

[SgWRX]

DBR issues here also. it'll render to 100% then lock up, i have to end task on 3ds max, but before i do i can save the rendered frame window image also have the issue with canceling while DBR rendering, using "subset of scene" doesn't work with DBR, and the mentalray "render selected" button in the RFW also gives me DBR problems. in the past, i've deleted my user folder: C:\Users\username\AppData\Local\Autodesk\3dsMaxDesign\2014 - 64bit\ENU (kept a backup copy) and that seems to fix all that 'ales ya, but only for about a week. I've not had the time to compare a new ENU folder contents with older ones. i suspect a lot of Max issues arise with customizing the toolbars or menus, plugins on one render slave not present on another even though you're not using them in the render, and maxscripts not present.

 

as for the brightspot in your render, seems to me i've run into that before. it might be to do due incrementally adding to the finalgather map? maybe build it from scratch? maybe delete that car, or make it un-renderable and see what happens?

[Matt McDonald]

Which version of Max are you running? DBR with Mental Ray has always been buggy at best. Your raytrace acceleration must be set to BSP2 and "use placeholder objects" must be checked. That should get it working. However, I have never been able to cancel a distributed job and not have the whole thing crash on me.

 

Regarding your hot spot. A couple of things come to mind. Do you have GI turned on? It could be a weird photon issue or I wonder if you have an oldschool raytrace material or map applied to that one car.

[chrishuntsman]

@charris - I tried the two-framed animation idea, it worked about 50% of the time. It would still hang up at 100% and at cancel rendering.

 

@SgWRX - thanks for the tip on deleting that user folder. I have installed the only plugin I have (itoosoftware) on all the slave computers, but I haven't stilled any maxscripts on those computers (I only have sweep profile and floor generator).

 

The hot spot went away when i turned off the sky associated with the sun in the daylight system. I don't think it had anything to do with the car. But you are right on the incremental FG, it didn't show up until I upped the settings there.

 

@Elevation - I am running 3ds max 2015 (up-to-date according to autodesk application manager). I don't have GI on, probably should but don't. I am using the MR arch & design car paint material, applied to all the cars with multi/sub maps.

 

When rendering, is there a recommended amount of hard drive space you should have? I am wondering if one of the slave computers might be filling up too much of their hard drives.

 

Switched over to Backburner today. Hopefully that doesn't present a whole new set of issues

[chrishuntsman]

@charris - I tried your tip on rendering out two-framed animations, it would work fine about 50% of the time. still unpredictable.

 

@SgWRX - thanks for the tip on deleting that user folder. I only have one plugin, itoosoftware, which I have installed on all slave computers. as for the maxscripts, I have only loaded two, sweep profile and floor generator. I will try removing those scripts from my machine and see if that does anything. You are right about the incremental FG causing that blowout, or at least making it visible. doing a draft FG it wouldn't appear, but once i upped the settings it showed up. Anyway, I turned off the sky portion of the daylight system and then that went away.

 

@Elevation - I am using 2015. I have BSP2 set (read in some forums to switch to BSP to resolve this issue though, which i tried with no success). Placeholders is checked. These are the settings I have had from the beginning of DBR. I don't have GI turned on, i should but don't. The car material is the A&D car paint material with multi/sub materials.

 

when rendering, how much free hard drive space is recommended? maybe one of the slave computers is maxing out?

 

thanks for your advice and help, i work in an office where no one has even heard of 3ds max so its nice to have someone to turn to.