Saturday, January 26, 2008

Tips and Q+A with Jamie Cardoso


My co-author on the book: Realistic Architectural Visualiztion with 3ds max and mental ray, Jamie Cardoso, has sent me a number of tips and a Q+A, that we thought might be nice to post on this blog. So you should see a number of new posts in the next few minutes, I hope you like them.

Roger C.

Grainy Quality to mr Renders

Q + A With Jamie Cardoso: Grainy Quality to mr Renders

Question: I bought your book Realistic Arch. Vis. And have gone through the first interior room tutorial. I’ve been trying to learn Mental Ray for a year now, but one thing I can’t figure out is why the renders of your files have this strange grainy quality to them. I’ve never produced a render with this using my own files, and I can’t figure out what it is about your settings which could be causing this. Can you please advise?

Jamie: This is to do with the fact that the render is at a small output size and also when the light's radius values are very high. This artifact happens with every high end rendering engine. Moreover, it frequently happens in enclosed scenes where lights (more than one) are bouncing across far too many objects.

There are 2 ways of by passing this:

1-To keep it at a small render size and get rid of the graininess, one should increase the U & V mr light samples (under area light parameters) to a point where there are no more grains (the value of 10 should be enough). This process will require some test renders, and it will increase the render times dramatically. By the way, this subject is mentioned in the book, at the end of the interior daylight tutorial.

2-The most common option amongst Hollywood film companies and 3D visualizers, is to render at higher resolution (IE 2500 pixels and above), and later decrease its original output size (IE 800 pixels) in photoshop etc, for web or e-mail purposes. Higher resolution renders are normally used for movies, publishing or marketing purposes. By the way, the big size render tutorial of the book cover image is also covered in the book.

When going through this tutorial, as mentioned in the book: save first the fg file by checking the read/write file function and clicking render at draft sampling settings (IE box filter; samples per pixel minim. 1/4 maxim. 4), the render size should not be higher than 500 pixels . Once rendered, the fg should be saved by then. The next step is to keep the read/write file function checked and also check the read only (fg freeze) this time around to ensure that the fg process will be bypassed. Finally set the final render output size to 2500 pixels or higher followed by also increasing the Sampling settings (IE gauss or mitchell filter type, samples per pixel min. 1 max. 16 or 64).

In both options, the rendering times will increase considerably however; the 2nd option is more reliable and professional.

Distributed Bucket Rendering, Windows Firewall Updates

Tips from Jamie Cardoso #1: Distributed Bucket Rendering, Windows Firewall Updates

For distributed bucket rendering, Windows firewall updates are now blocking the mental ray distributed bucket rendering system for max 9 and 2008

(IE raysat_3dsMax2008_32.bat;raysat_3dsMax2008_32.exe;raysat_3dsMax2008_32server.exe).

All the above for max 9 and 2008 need to be included in windows firewall exceptions list. To do so, simply go to: control panel + security center + windows firewall + in the exceptions list, simply add (program...) the list of raysat files for max 9 and 2008,one at the time. By the way, the raysat files can be found in: C:\Program Files\Autodesk\3ds Max 9 and/or 2008\mentalray\satellite.

Distributed Bucket Rendering

Tips from Jamie Cardoso #3: Distributed Bucket Rendering

IP addresses are more reliable and recommended by hollywood movie companies and visualization companies however, depending on the way one's network is set up, one may need to type the computer's name instead in order to make it function.

Big Marketing Images

Tips from Jamie Cardoso #3: Big Marketing Images

When rendering images bigger than 4000 pixels (marketing) with mental ray in one computer only, make sure that one uses the network render instead of distributed bucket rendering as mental ray may not render them. (depending on your machine's specs) To bypass this, simply send the file as net render and choose (check) split scan lines. Once that is checked, define the strips setup (pop up dialog box). I normally keep the settings as default and only change the overlap to 1 and check the delete the temporary images upon completion function, however one can choose the settings that best suits their computers.

Arch & Design shaders

Tips from Jamie Cardoso #4: Arch & Design shaders

I normally use customized materials, but for those who use default arch & design materials:

When applying shaders such as satin varnished wood shader and etc, one should be careful when network rendering. The satin varnished wood shader normally generates temporary bitmap/s( IE finishes.flooring.wood.plank.beech.jpg) in a localdrive. When sending the 3ds max to net render across another machine/s, the other machine/s may not have this file, which will subsequently generate errors in backburner. Even the backburner's include maps. function doesn't work at times.

The most reliable way of re-pathing any missing maps is to first use the archive tool to archive the file (IE file + archive..). This tool will also collect all the maps in your 3ds max scene. Thereafter one should use the asset tracking tool to re-direct all the missing files to the area where your archived files are. If there are any unused paths in the asset tracking dialog, simply strip them with strip path tool. Do not use the the include maps function from backburner.

By the way, to configure paths with the asset tracking, simply select any path from the asset tracking dialog box list, and right click. A pop up menu should appear. One can choose to either browse... or strip from the pop up menu. When browsing for a file, ensure that the map is found, selected and opened...or it won't reconfigure the path on the asset tracking. To access the asset tracking tool, simply go to file, on the drop down list, choose asset tracking.