Map the illuminance readings you took across a working plane as a grid, check the average against the AS/NZS 1680.2 target for the space, see the unevenness a single average hides, and read off the uniformity ratio for Assignment 1.
Steps 1, 3, 4, 5 and 6 use no tab. To use tab 1 you need your readings recorded as a grid, so note the position of each reading as you take it, not just the value.
A lit space raises two questions: is there enough light on average, and is it distributed evenly? They are different, and a space can pass one while failing the other.
For the amount, compare your average illuminance against the maintained-illuminance target AS/NZS 1680.2 recommends for the space type. For the evenness, use the uniformity ratio U0 = minimum ÷ average: near 1.0 the darkest spot is almost as bright as the typical one, while a low value means dark patches the mean conceals. AS/NZS 1680.1:2006 recommends U0 ≥ 0.7 over a task area such as a desk, ≥ 0.5 over a space under general lighting, and ≥ 0.3 along a circulation route; a related, stricter ratio is diversity = minimum ÷ maximum. A space can hit its target average and still feel patchy, which the ratio reveals but the mean hides.
Pick your space type and what your grid covers, then set the grid to match how you walked the space and type each reading in lux into the cell at that position. AS/NZS 1680.1 asks for a regular grid: equal, near-square cells no more than 1 m apart, a reading at the centre of each at working-plane height (0.7 m for a desk, 0.85 m for a bench), and at least 9 points. Leave a cell blank where you did not take a reading; blanks are ignored in the maths and shown empty on the map.
The standard says how much light a space needs; the NCC caps the electric lighting power used to deliver it, as a maximum illumination power density in W/m² (NCC 2022 J7D3). Enter the floor area your lights serve and their total rated power to see the density, how it compares with the NCC figure for your space type, and how many lux your average buys per W/m².
Amount. AS/NZS 1680.2 sets a maintained illuminance per space type (the targets in the space-type list, from the Week 8 brief); the tool reports whether your average sits below, on, or above that range. It allows a 20% margin above the top of the range before flagging "above target", since a little headroom is normal, and reads any average below the bottom of the range as falling short. Overshoot is not a failure, but note it: over-lighting wastes energy and can add glare.
Evenness. AS/NZS 1680.1:2006 defines the uniformity of illuminance as the minimum ÷ average over the measurement area (Clause 1.4.10), the U0 reported here. Its Table 3.2 recommends U0 ≥ 0.7 over a task area, ≥ 0.5 over a space under general lighting, and ≥ 0.3 along a circulation route; the application parts (AS/NZS 1680.2 series) may set lower values for particular spaces. Diversity (minimum ÷ maximum) is a different, stricter ratio some guides also quote, so name which one you are reporting.
Measuring so the numbers compare. Appendix B3.4 of AS/NZS 1680.1 sets out how to measure: divide the area into identical rectangles, as near square as possible, and take a reading at the centre of each at working-plane height (0.7 m for desk tasks, 0.85 m for bench tasks). Points should be no more than 1 m apart, with the spacing along each axis within 10% of the other, and no closer than 1 m to a wall. In a space under 25 m², cover the whole area with at least 9 points; in a larger one, measure at least 9 m² that takes in at least 4 luminaires. Scattered points cannot be compared against the standard, and the minimum in the ratio is the lowest grid reading, not the darkest spot in the room. The standard's check is of the electric lighting, so measure after dark or with daylight excluded; readings taken with daylight describe the space as used, but say so when you report them.
The same readings as a map, so you can see where the light falls away.
Each cell is shaded by its reading (dark = low lux, bright = high lux) and the lowest and highest readings are ringed. The mean gives you the amount of light. It cannot show you the spatial pattern: a bright patch propping the average up, or a dark corner off the task. Read the map alongside the ratio before you decide what a designer would change.
The figure you submit for Assignment 1 must be one you build yourself, not a screenshot of this tool: labelled axes with units, a legend where needed, and a caption that tells the reader what to notice. Building it is the skill being marked.
Each filled cell is shaded on a perceptually-uniform, colourblind-friendly (viridis) colour ramp, normalised so the darkest reading sits at the low end and the brightest at the high end. Stretching every map to the full ramp would make a very even plane look patchy, though: readings of 480 and 520 lux would show as purple and yellow. So the scale always spans at least half the average illuminance. When the readings spread wider than that, lo and hi are simply the minimum and maximum; when they do not, the scale is widened evenly around them, the readings fall in the middle of the ramp, and a bracket on the legend marks where they sit. Blank cells (no reading) are drawn as dashed outlines and excluded from the scale. The single lowest and highest readings are ringed so the extremes driving the uniformity ratio are easy to find on the plane.
What the distribution of readings looks like at a glance.
The same readings as a box plot: the box spans the middle half (25th to 75th percentile), the line is the median, the whiskers reach the minimum and maximum, and each dot is one reading. The shape it makes is the distribution a single average lux value flattens away: tight and symmetric, or stretched by a few dark or bright outliers.
Quartiles use linear interpolation between order statistics: for quantile q over n sorted readings, position = (n − 1) × q, and the value is interpolated between the two neighbouring points. The box spans the 25th to 75th percentile (the interquartile range), the centre line is the median, and the whiskers reach the full minimum and maximum. Every reading is drawn as a jittered dot so you can see clustering the five-number summary hides.