Josh Mossotti

A quick show of hands… How many of you have setup a scene, possibly like me with countless render layers all laid out and ready to rock, kicked off a long render and went to sleep with all the comfort of knowing when you arrive back at your bench you will be greeted with thousands of vibrant images eagerly waiting a composite and find out you have been underhanded by your trustee friend Mental Ray? You have 10 GB’s of solid black images. Darker than zero. I’m talking about a depth and void only witnessed through the eyes of a betrayed and heartbroken artist.

Well no more!!

I am sure most people have eeked out solutions of their own when presented with such egregious insubordination. I will add to your quiver of handy solutions with one that has come to serve me well.

First I would like to say I am not certain of the cause of this particular problem but I’ll note that it is a problem with the Mental Ray settings in the scene rather than the possible abundance of mib shaders. More than likely if you test out a plain lambert material when Mental Ray turns itself into a conveyor belt of blackness you’ll find nothing renders. It bothers me to no end to encounter problems that I do not understand the ‘why’ involved, but possibly as I dissect the solution a bit I will find out more.

Here are the steps I have come accustomed to in overriding said problem.

Save your latest scene and save a new version with some variance identifying the MR fix. In the top right-ish of your maya window select the downward facing black arrow that drops down a selection of options: Absolute Transform, Relative Transform, Rename and Select By Name.
Select ‘Select By Name’, type *mentalray* with the asterisks to select everything with mentalray in its name. Press enter, then delete. Now at this point if you continue in this scene Mental Ray is all but completely disabled. It has removed everything including the render globals data. Save this scene as your _MRfix.ma. I normally exit the program at this point and reopen. When you open this scene again Mental Ray will naturally restore its settings and the problem has been rinsed clean out of your file. Save this as the next consecutive iteration of your convention and you are back in business.

I might post screenshot images of this simple process but right now I am friggin’ busy. What is nice about this solution is in the past I would worry about possible problems based on the shader systems in place, which is too vast to break down. This allows you to leave all render layers and shaders in place, and will have you sleeping easy again in no time.

I try to post things that seem rather excluded from the world wide web of information. I was unable to find anything pertaining to this problem or its solutions. I hope this helps otherwise what the hell are you doing here. You googled Mental Ray Black Render Frames. Jog on !!