MAXWELL FOR SKETCHUP
TUTORIAL part 2
This article is the second of two parts tutorial about the use of the Maxwell for SketchUp on architectural visualization.
‘Materials in the plugin exist as a set of parameters which are attached to each individual SketchUp material contained in the document.’
I normally create and asign each material as Sketchup material, then do the editing in the plugin’s Material Editor user interface.
Here are the settings for some of the materials used on the scene.
For grass I used type SSS (Single Sided) and gave a texture from Peter Guthrie’s grass tutorial part 2:
‘Glass materials should only be used on objects which have a closed volume.’
Image Based environment type was selected for illuminate this scene, I used Peter Guthrie’s 1928 Dusk Sun HDRI.
With the use of HDRI map my shadows were not sharp enough, so after reading the making of the Museum ‘Field Project’ by Bertrand Benoit, I decided to test Bertrand’s trick by lowering the gamma of the HDRI in Photoshop.
Render preview using the HDRI with gamma 1.00
Render preview using the HDRI gamma lowered to 0.75
Image Based settings used
Camera and camera settings
‘For each Scene in your SketchUp document, the plugin will create and maintain an associated Maxwell camera.’
In SketchUp I set my camera to perspective and adjust cameras field of view, then navigate the scene until I find a point of view that is interesting and do small adjustements, when Im happy with the view I save the scene.
Before rendering, I do set up my camera, by opening the Maxwells Scene Manager and selecting the tab ‘camera’.
In this case I set the output resolution to 1600×800, focus and exposure could be set to the default ‘automatic mode’, personally I dont like to leave it to the luck, so I adjust as follows:
f/stop = 11 or higher, lower values causes DOF which is going to make to render slower (unless I want to use DOF, then I go for lower values).
Shutter and ISO film are adjusted to lighting conditions (as a real camera).
Now do a test render and adjust shutter and ISO.
Click the Set Focal Distance botton, you will be prompted to select a point in the scene, select a point on a face you want to be focused.
To finish, I set my camera to ‘Two-point perspective’ in order to correct the perspective distortion. Shift Lens allows to shift the camera’s film along its X and Y axes, with respect to the lens.
‘The effect of the shift lens cannot be visualized in the SketchUp viewport, due to SketchUp API limitations. It can, however be visualized using Maxwell Fire’.
Maxwell’s plugin is so simple to use. To render just launch Maxwell Fire, by default, the scene will immediately be transferred to Maxwell Fire and its rendering begun, the engine settings are quite minimal.
SL: Sets the sampling level at which rendering will stop.
Threads: Sets the number of threads which will be used by the render engine.
Engine: Allows you to specify whether rendering be done using Maxwell Render’s Draft
or Production render engine.
When a final image is being rendered, it is desirable that inadvertent actions, for example, scrolling in the SketchUp viewport, be ignored, so that the rendering is not interrupted. This may be done by enabling the Lock button.
Once the render is completed I saved the image as PNG. Maxwell’s plugin unfortunately does not support channels.
If you use very large HDR maps or you dont want to compose your sky in postwork, then you don’t need a sky alpha channel. In some cases I use Maxwell’s Physical Sky and then compose a sky image in the background with Photoshop.
after some experiments I found my own technique to generate a sky alpha channel with this simple method:
first, hide any emitters or IES in your scene
In Maxwell Scene Manager set environment type to sky
Set sky type to ‘constant dome’
Customize zenith and horizon colours to magenta
Change then environment type to Image Based
In Image Based, set the background cannel to ‘active sky’
And disable the rest of channels: reflection, refraction and illumination
Turn OFF sun
Launch Maxwell Fire, and this is how the image should look like, save the image.
Now you can compose your raw render with a sky backplate.
In this case I did not compose the sky in Photoshop, just left the one integrated with the HDRI used on environment.
Final image, after adding subtle corrections in Lightroom and noise reduction in Photoshop.
That’s it, hope you find this tutorial helpful, thanks for your interest.