Improve false colors

If falsecolor images aren’t mapped good, there could be several reasons and most of them can be solved easily:

Case 1

Material is not mapped good near surface edges or holes edges (color is changed towards green/blue) – start Show sensors and values tool  to see how they are positioned and if there are sensors near edges. If needed recalculate sun exposure for that surface with lower distance between sensors.
This kind of problem shouldn’t appear very often.

Case 2

If material is pasted completely wrong and sensors seem to be positioned well over plane surface, check if the face have collinear corner points (like some edge is composed of more than one line). This can cause wrong interpretation of plane corner points when false color material is pasted.
2 possible solutions – automatic and manual one:

  • Automatic model cleaning – If number of problematic surfaces is rather big, Sketchup model should be cleaned before SunExposure extension is used. To clean model use one of next tools:
  • Manual model cleaning – For problematic surface(s), find edges that are composed of more than one part. Delete edge lines and draw a single line instead (put line Layer to be the same as face layer).

After you clean the model recalculate SunExposure and import results again.
Note that for some surfaces this automatic cleaning may not solve the problem so manual cleaning is required.

Case 3

False color material pasting is obviously wrong, and surface(s) have very irregular shape or aspect ratio is too big/small.
Solution is to try to replace problematic surface(s) with one or multiple simpler surfaces, with more balanced aspect ratio and also put lower sensor distance for the surface.
Then repeat calculation and results analysis and import.

Case 4

If none of previous cases solve the problem, please inform extension authors on

Strange images

In order to color the whole surfaces from a set of discrete points, SunExposure uses several  interpolation techniques.  Depending on the shape of the faces, interpolation algorithms perform may leads to better or poorer results.

SunExposure automatically selects the interpolation algotithm that should give the best results.

In certain cases Automatic image interpolation algorithm selection, doesn’t give satisfying false color results on surfaces with constant values in sensors (over complete surface area or some part of surface area). If results aren’t as expected, try some of tips listed below:

  • Increase Level of details for sensors generation in  “SunExposure dialog”, and Run calculation for problematic surface’s with “Run selected“.
  • Change scale type to “Automatic linear scale” and “Rerun images“.
  • Change color limits in SunExposure dialog, to be further from exact sensors values for the problematic surface and then “Rerun images.”
  • Decrease number of colors in the palette – to avoid very narrow range of values for a single color.
  • Change image interpolation algorithm in ‘Preferences dialog’. Read Interpolation algorithms

Have in mind, that no interpolation algorithm is perfect :)

Sensors are not visible

If after calculation sensor points aren’t visible when toggled on, check menu option View->Guides. SketchUp treats construction points objects the same way as guides and if this option is not checked, sensors points won’t be visible.

Manage calculation time

In SunExposure calcultion time directly depends on the size of the model, on the number of surfaces to calculate and the density of sensors defined.

To use SunExposure more efficiently, we suggest:

  • to hide useless layers whose objects would not change SunExposure results (interior walls for instance)
  • to avoid selecting unimportant surfaces. Select all would work but would lead to the calculation of a large number of uninteresting surfaces
  • to use first a “simple” level of details to avoid launching longer calculation before the complete validation of the model
  • to avoid launching “Very detailled” calculation on all surfaces
  • to adapt the level of details to the size of the surface to calculate. A “Very detailled” level may be well adapted to Windows for example whereas it has little interest for a large outside area or a whole street

Message “Dispatcher not launched”

During a first calculation, an error message may appear to inform that the calculation was not started.

This message appears generally on Windows during a first calculation for a project or when the output directory has been changed.

When Windows works in a directory for a first time, it operates a series a verification that may take a long time. The surveillance mechanism inside SunExposure may then consider than some process is not working properly. We chose in that case the stop the calculation (even though waiting longer for Windows to finish would work).

It is sufficient to relaunch the calculation to solve the problem in most cases.

You’ll find in the Help pages other methods to solve the problem if it remains.


Some surfaces seem not calculated

A face in Sketchup has an orientation. Normal to the face may be oriented towards the outside (towards the sun in our case) or towards the inside (of the building in particular).

During SunExposure calculation, if the normal is oriented towards the interior, the calculated face is inside the building and never “sees” the sun. The face visible from the outside then appears not calculated.

To calculated that face correctly, you need to “invert the face” so that it “sees” the sun and relaunch the calculation for that face.


How to block False Colour palette ?

When I am satisfied by a false colour palette calculated by SunExposure, how can I block it so it is not recalculated during next calculation?

SunExposure systematically recalculates the false colour palette so that it is best adapted to the calculated surfaces in the model.

When you are satisfied with a palette, just go to the False Colour tab, change “Automatic Palette” into “Manual Palette“. The current palette will then be blocked and will be used during further calculations without modifications.

Sketchup 2014 [Windows] : If I double-click on a model on the network, SunExposure does not load correctly

In Sketchup 2014, the double-click on a skp model on a network (not on local disks) leads to an error in environmental variables for Sketchup.

Because of that, extensions cannot initialize properly. For example, with SunExposure, Sketchup console will display a long error message indicating that many SunExposure files could not be loaded.

As this bug is independent of Sketchup we cannot correct it.

However there is a version a Sketchup 2014 called MA (Maintenance 1) that corrects the problem.

For more information, have a look at the technical site for Sketchup versions and look for the paragraph “What’s new in SketchUp 2014 M1

AnimGifViewer 1.0

Preview and explore step by step animated GIF images.

AnimGifViewer has been developed by De Luminae to enable users to play animated gif files and also to explore them step-by-step, in particular files created by RadSunpath. We could not find an easy to use and understandable animated images gif viewers on Internet, which can explore images embedded in animation one by one, and decided to create one.

Interaction between qualitative and quantitative approaches in the teaching of architectural design

In order to improve the understanding of daylighting by students in architecture, we seek a better integration between scientific and architectural languages and we try to strengthen the links between quantitative (knowledge on daylighting as a physical phenomenon expressed in mathematical terms) and qualitative (knowledge on daylighting as a modifier of luminous ambiance expressed in a descriptive way using natural language).

This will help students to reach a better control of the phenomenon, to build their own criteria and to apply them in the sketch phase of architectural design. It may also be a basis for a aiding-system for the design in the sketch phase. We used fuzzy set methods and multivalued logicsto model the building and its environment and to structure knowledge taking architect’s preferences into account.

Interaction between qualitative and quantitative approaches in the teaching of architectural design

Measurements and qualification of luminous ambience in daylighting

This paper is centered on the relationship between intuitive and quantitative approaches for the understanding of luminous ambience in order to formalize criteria for the classification of luminous ambiences.

We measured luminance and illuminance levels on glazed and opaque surfaces in interior spaces and built a synthetic scheme of these levels. We then analyzed and compared these measures and their interpretation to impressions felt by several subjects in the spaces, or to intentions expressed by the architect during the design of the project when available.

This comparison has proved itself very meaningful and shows that many relations between the intuitive approach and quantitative measured data may be established. The second part of the work deals with the definition of criteria to classify ambiences. They allowed us to prepare a computer tool, based on neural nets which will be used to help architects store and browse through a large number of images.

Measurements and qualification of luminous ambience in daylighting

A comparative analysis of luminous ambience designed for equivalent functions

The first part of this work focused on the elicitation of links between qualitative and quantitative approaches for luminous ambience in daylighting. We measured luminance and illuminance levels on glazed and opaque surfaces in interior spaces. We analysed and compared these measures and interpretations to impressions felt by subjects in the spaces, or to intentions expressed by the architect during the design of the project when available. This comparison has proved itself very meaningful and shows that many relations between the intuitive approach and quantitative measured data may be established.

In the second part, we performed a comparative analysis between qualitative and quantitative data for luminous ambience designed for equivalent functions. It helped us better define the meaning of the qualitative terms used by subjects. It also helped us enrich the quantitative point of view through the definition of new notions such as the rhythm of repetition of contrast levels or the size of surfaces having a particular level of luminance. This work can also be used to enrich the language on luminous ambience and be of great help on the classification of luminous ambience. We use this comparative approach in teaching, in our school of architecture.

Beyond quantitative data, our method allows to perform an analysis closer to architects’ needs and expressed in his language. This link between qualitative and quantitative allows to fill the gap between scientific technique and architectural design. It may be included in RADIANCE, to provide results related to architects’ intentions.

A comparative analysis of luminous ambience designed for equivalent functions

Comfortable and/or pleasant ambience: conflicting issues?

We present here a theoretical study about the relationships between comfortable and pleasant ambiences. The notion of comfort is not sufficient for the study and design of ambience. Ambience is defined here as the way the environment affects a subject. Subjects are naturally affected by a global ambience. However, for the analysis, we distinguish between luminous, aesthetic, thermal, acoustic…ambience.

Comfort definitions exclude the notion of tension and psycho-physiological disturbance on subjects, whatever its level may be. The question of pleasant ambience is naturally not fully answered. However, one way to define a pleasant ambience especially includes the notion of tension on subjects affected by an ambience. The case of the house on the cascade by F L Wright perfectly illustrates this point. This house is situated on a waterfall whose acoustic level is above all norms. Therefore this house is not comfortable. However, it is widely recognised and taught as a reference for its pleasant ambience, especially for the contribution of the acoustic ambience. In this case, the comfortable and pleasant sides of ambience are conflicting.

As modern technologies are improving, artificial lighting and ventilation, for example, can lead to perfectly comfortable ambience. However, it is widely recognised that natural lighting and passive ventilation are more pleasant.

We develop this discussion on the basis of the results of a study on qualifications of luminous ambience and on other theoretical and technical works. We believe that this investigation is nowadays important because the technological sides of ambience are improving: comfortable ambience may be designed, but are they pleasant? We think that a very global view on ambience is now needed.

Comfortable and/or pleasant ambience: conflicting issues?

Dimensions of personality in the responses to luminous ambiences

In this multidisciplinary work, we propose a practical framework to study the variability of subjective responses to identical luminous ambiences (atmosphere). We focus on the influence of personality dimensions.

Architects build spaces for which they define functional characteristics and an esthetical concept, while considering the quality of ambiences. The success of a building depends on the subjective perceptions and the behavioural responses of users regarding these functionalities and ambiences. In most works on ambiences, the user is generally considered as an “average user” (mister anybody). The importance and variability of the subjective character of responses has often been mentioned. However, we still do not have effective indicators on the relationship between personalities and the sensations of comfort and pleasure in a luminous ambience.

The purpose of this work is therefore to study the relationship between the perceptivo-cognitive handling of luminance and chromaticities and the way social spaces are occupied and used depending on their luminous ambience.
We study the behaviour of subjects in a laboratory and on sites (in rest areas). At the same time, we study the luminous ambiences in these areas. We obtain indicators on subjects:

  • 1) by measuring perceptive sensitivity to luminous stimuli (ERP method, in laboratory) with an electroencephalogram on 48 people in order to detect high and low level sensation seekers according to their sensations of pleasure
  • 2) by observing the behaviour of the same subjects in rest areas and by discussing with them with a questionnaire.

We obtain indicators on existing luminous ambiences (with natural light and artificial light to complement it) in rest areas by measuring luminance, illuminance and chromaticities on opaque and transparent envelopes in these areas.
We then greatly modify luminous ambiences in these areas (by partially covering windows and by modifying artificial light). We then repeat the observations with the same kind of subjects.

Dimensions of personality in the responses to luminous ambiences

Luminous ambience, quantitative/qualitative data and subjective response

This paper presents several years of research in luminous ambience in daylighting. It began with works on the relationship between intuitive and quantitative approaches for the understanding of luminous ambience. We collected quantitative data from measurements of illuminance levels on glazed and opaque surfaces in interior spaces.

From these measures we could build an interpretation related to the luminous ambience. They were compared to what was expressed by interviewed subjects in these spaces or to intentions expressed by the architect during the design when available.
At the end of this work, a first issue was: how could we explain that comfort and pleasantness of an ambience may often be conflicting? We investigated this question and showed that comfort is not sufficient to express the quality of a luminous ambience and that some degree of “discomfort” may be needed by individuals to feel an ambience as pleasant.

Confronted to the variety of answers given by people about luminous ambience, we tried to understand how subjective responses to a luminous ambience relate to the dimensions of personality. As this particular point of view seemed to have seldom been investigated, we decided to start a project specifically focused on this subject. The purpose of this paper is therefore to sum up this line of research, from quantitative measurements to dimensions of personality.

Luminous ambience, quantitative/qualitative data and subjective response

Measurement and interpretation of luminous ambience

This paper presents part of a multidisciplinary work with three teams: two laboratories of psychology and a laboratory of lighting/architecture. We concentrate here, within the project, on activities on luminous ambience and focus on the lighting/architecture part. The problem we studied was:

  • How is it possible to concisely express the variety of luminous ambience qualities on the basis of a large number of light measurements? More precisely, in order to analyse the quantitative data collected from measurements, we intend to define interpretation models. The result of these interpretation models should be easily usable for further analysis and understandable by architects. Architects do not manipulate expressions such as luminance levels. In order to express their intentions for a luminous ambience, they use qualitative and descriptive expressions.
  • On the basis on these interpretations, how can we change the existing concept of artificial lighting for a space in order to lessen energy costs, to keep a good performance of lighting and to improve the comfort and pleasantness of users? More precisely, comfort and pleasantness are closely linked to contrasts thresholds, gradual ranges of luminance and chromaticities on the interior envelope. Artificial lighting is used by the general public and designers not only to reach a sufficient level of lighting on work surfaces, but also to increase or decrease contrasts and gradual ranges of luminance and modify the colour of the light on the interior envelope in order to reach a comfortable and pleasant ambience. In that respect, we can say that the expenditure in electric energy is also due to the fraction of artificial lighting used to create comfort and pleasantness of ambience.

To address these two questions, we have studied existing luminous ambience in two sites in Paris. The spaces under study were rest areas. We defined the method for light measurement on the opaque and glazed interior envelope (with luminancechroma and luxchroma meters) in mixed lighting (both natural and artificial). We interpret the measurements in terms adapted to architects. We defined the concepts for different luminous ambiences and built these modified ambiences in the sites themselves.

Measurement and interpretation of luminous ambience

Simulation of Luminaires in Radiance: Verification Method

In the process of architectural design architects can use different software tools for modelling and simulation. These programs allow them to simulate imaginary buildings, and verify their intentions, preferences and respect of norms, in order to bring the resulting ambience closer to architects intentions. On the other hand, programs follow strictly defined geometrical and physical laws, which give quantitative accuracy to the project.

For modelling and simulation in architecture there is a great number of different computer programs available on the market, such as AutoCAD, 3DStudio Max, PovRay, Radiance, etc. All these programs offer similar possibilities for modeling of geometrical primitives, but their capability to simulate luminous ambiance of the building is different. Definition of luminous ambiance is rather complex, and it involves description of artificial (luminaires) and natural (sun, sky) light sources, building position and environment, and materials used for building interior and exterior. Lighting design programs are software tools for calculation and visualization of luminous ambiance.

Due to the complex nature of light, all lighting design programs, in the process of light modelling, involve some simplifying assumptions, which lead to some amount of calculation inaccuracy.

The aim of this paper is to propose a method for evaluation of the error introduced by computer simulation of luminaires. The method compares luminaire simulation results from Radiance2 software against results obtained from lighting calculation methods proposed by “Illuminating Engineering Society of North America” – IESNA.

Simulation of Luminaires in Radiance: Verification Method

Will it really be soft and calm, my luminous ambience?


The intake and distribution of natural light in interior spaces are imagined early in architectural design: placement of openings, orientations and inclinations, depth of spaces, etc. are defined during the first sketches. However, existing design aid tools are ill adapted to this early phase where the building is not completely defined.

In order to help overcome these difficulties, we propose to use the models of buildings in design. They are placed under an artificial or natural sky. Inside images are displayed via micro-cameras on a computer screen. The software computes correspondence between points of the image and luminance levels in the actual models. Knowing luminance in every point of the interior envelope, the software we are developing, analyses the luminous ambience on the image.

The main contribution of this work lies within ambience analysis on images, expressed in qualitative and quantitative terms. For example, the result of the analysis of a field of vision is “calm and clear ambience” or “tense and rather dark”, etc. Definitions of such qualitative terms, based on previous works, are shown to users along with related quantitative and reference data.

These methods help the use of natural light, hence of renewable energy. It allows good use of the natural luminous flux: to have enough but not too much (avoiding visual discomfort and overheat). It also allows architects to follow the aesthetic evolutions of the ambiences they imagined.

Will it really be soft and calm, my luminous ambience?

RadSunpath 1.0

Create animated representation of sun path and shadows during the day.

RadSunpath has been developed by De Luminae to allow users to create a set of Radiance images for a project, for selected date and include them into final animation file which represents the sun and shadows path during the selected date.

Import building geometry defined in SketchUp program with RadSunpath plugin.

Building geometry and materials defined in SketchUp and exported to radiance format with su2rad plugin, can be directly imported into RadSunpath with the SketchUp plug in we provide. This will enable easy simulation of sun and shadows path during the day, even for projects defined in other software like SketchUp.

Luminance Maps

Luminance maps show luminance zones calculated on the interior envelop of the room. They give information on luminous comfort (the quality of light).

These maps are produced using the same climate conditions and geometrical environment as before.

Energetic Illuminance Maps

The energy studies of urban areas allows to easily highlight zones for high potentials or possible difficulties for natural lighting.

These maps are used in many situations : evaluation of potentials, specific usage zone positionning, SDAL study, etc.

These maps requires few data on the project and therefore may be calculated at early stages.

RadDisplay 1.1.1

Radiance image viewer and analysis for architectural light study

RadDisplay has been developed by De Luminae to allow users to view Radiance image format without any Radiance knowledge and to help to investigate these images using false color images.