Hi all!
This is my first WIP thread so I will briefly introduce myself: My name is Carlos Mazon and I am a spanish architect and architectural illustrator living in London.
My introduction to the Arch Viz world was a few years ago with Blender an Yafaray (http://bit.ly/gTLqbA) but when I moved to London I had to swap to 3DsMax and Vray for profesional reasons. You can have a look to a few of my professional works in my website www.carlos-mazon.com
I recently received a job from a Spanish architect and I decided to try the new Cycles engine.
THE PROJECT
The main idea of the project is quite funky one: is a Kindergarden where graffiti artists go to teach the children how to draw. I was quite happy about this because I knew I would be able to try a cool approach to the image 
This reference was provided by the architect:
ART DIRECTION
The project is located in a ugly suburban area of Alicante. This was quite a problem as the architect wanted an aerial view and it was going to be a challenge how to hide the ugly brick buildings and give focus to the main building. I decided to make a late sunset view so I could have all the façades in shadows and make a bright interior of the main Kindergarten.
I knew I would have to have lots of children playing, graffiti, parents looking around… the image was more about showing the “mood” of the place rather than the shape of it.
REFERENCES
Before all, I searched on-line for pictures of aerial sunsets so I could see the real behaviour of the light, shadows, reflections, ect. I always do this to try to get the most realism of the final image.
Here you have some of them:
(sadly I did this early in the project and I don’t have the names of the authors of the pictures)
(to be continued…)
3D PROCESS
I exported the original 3dsmax model in .obj and began the fun in Blender
LIGHTING
I used and free HDR map of a sunset in Barcelona (http://bit.ly/13pM0Ua) and a Sun lamp.
The materials where almost all diffuse and I used really simple tileable textures from cgtextures.com.
I used a 25mm camera as I had to show a lot of the context. The image had to be printed in a A1 size, so I the output image was about 6k pixels wide.
I had an Nvidia GeForce GTX 670 and I think the image took about two-three hours to render (quite good time taking in account the size of the output)
Here you have the RAW render. Not really impressive, right? 
(to be continued again…)
Looks good and looking forward to see the progress of this. The only quite strange thing at the moment, is the grass blending in with the tiles. It would work more naturally with larger pavement tiles that plug-in between the grass bits.
Very impressive renders and concepts at the linked yafaray site and your site as well. How many of those on your site are cycles/yafaray/blender, since they all look top notch?
Nice to see that there are other architects around the forums :).
RENDER PASSES
This was one of the important parts as my workflow relies a lot in postproduction.
I needed different passes to easily select different elements of the image. In the 3dsMax universe this is quite easy (WireColor pass) but I found a few problems in Blender…
There is no way of render a Color pass without the texture, so I had to duplicate the file (this is usually an issue as if the client decides to change something you have to create a “Masks” file again) and render the Color pass from Blender Internal. I also had to edit the materials one by one which was quite a tedious task.
This problem would be easily solved if there was the possibility to render a pass with the Object Color or the Material Viewport Color (or even better: both!). If then somebody could make a scritpt to randomaly apply different colors to Object Color slot of Material Viewport Color this step would be a breeze! (Blender developers, if you’re reading this… hint, hint
{NOTE: I recently discover this thread http://bit.ly/14O8smI but I didn’t had time to try it. Even being a temporary solution it doesn’t looks too fast and relies in creating a copy of the scene, which is not the most optimal solution}
My output nodes:
All the passes together (cycles and internal):
Being able to select different elements and with one afternoon of work, here is the first Work in Progress for the architect:
(to be continued…)
Thanks njdimi, please keep reading this thread. I usually correct all that in postproduction, so I don’t usually pay much attention to grass textures in the render (photoshop images look usually much better).
Thanks very much! They were all Blender+Yafaray, but those are all quite old (two years or more). Please had a look to my Flickr (http://bit.ly/14O9kI7) if you want to see my current work.
You have a really nice architectural porfolio! Nice to see an “open source” mind coming out the AA 
WORK IN PROGRESS 2
After more adjustments, painted light, people, children playing, grafitti, etc… here is the second Work in Progress:
This was the version the architect used. My plan now is to improve the base render (adding more detail and improving some of the basic textures) to make the image better.
Please feel all free to comment or ask anything!
Looks like good progress! A few suggestions to help with the focus:
Perhaps make it a bit later in the day with a little tad less light, but add lamps around the area you want the viewer to focus on.
Also, you could desaturate the buildings slightly and add more colors to the park? Right now my eyes are being drawn to the space between the buildings where the light is coming from and not to the park.
I hope that helps!
Thanks, although I am working around the clock add more material related to green design.
This render is very impressive for one afternoon’s work! Do you mix all your render passes and do you all your post-processing in photoshop?
And I see that you have been painting people and tress. I have been using billboard people and trees as 2d planes in my scene and rendering them, to make sure that they are always the right scale (especially If there are many people and many trees, as I am in this scene) . In general, what is your preference on painting vs using 2d planes?
For the light painting, do you do it with respect to the z depth pass?
A curiousity when looking at the render: Imagining that all the paints and sprays are kid-safe and probably able to be washed with water, it looks rather interesting to do a single graffiti on glass/clad surface
