Life in a Dol house
2017 - Week 35

The Angle x 0.018 x The distance = The spread ​

I was awoken on Friday morning to the fragrant aroma of Lavender - I am still sleeping with all the doors and windows open, but protected by mosquito nets. 

After ablutions, I saw my neighbour Mario was processing the 2017 Lavender harvest.

This is still work being done completely by hand (and foot). I am probably 100 meters away from where the work was taking place, but the wind was in the right direction. Much like separating the wheat from the chaff of biblical times, the lavender seeds are separated from the stalks, in a manner unchanged for centuries.

Winnowing is the term which is used to describe the process in the case of my neighbour Mario, still all carried out without mechanical aid.

​The fragrant flower seeds once they have been separated from the husks and stems, will be processed by distillation to create the essential oils of lavender. Here in the village the Still still exists, although it is no longer used. But it is nice to see these ancient artisan methods still in use.

​Afterwards I was invited into Mario's Konoba (and it was not yet 9am) to sample Rakija, Prošek and a couple of other extremely well fortified liqueurs, the names of which I didn't quite catch, each served in Whisky Tumbler size gasses. 

The result is that even after extremely strong coffee, I still doubt my ability to function at anything more than 50% and my plans for driving into town had changed!

I discovered this week that I needed a beam spread table. 

That's not the sort of table for resting coffee mugs on, even though that is a nice idea, rather it's a mathematical tabulation of the spread of light from a given source.

I need to put the wiring into the study floor, for the ceiling lights underneath. 

The room underneath will have exposed beams, and I don't want to have wires showing, so I have to try and work out in advance where the lights will be placed, with the wiring hidden under the sub floor above.

This means that I need to think about where the furniture will go and where I want the lights to be. I have already purchased the low energy A+ rating ceiling lights and LED spotlights.


There are lots of terms used in lighting: Beam spread, measured how light is distributed from the lighting source; Beam angle, illumination which falls within 50% of the maximum light output from the source; Beam field, which is the area outside the beam spread, to the point where the light output falls to 10% or below.

The light output is measured in lumens and the intensity in Candelas, then there is the colour of the light, measured in degrees Kelvin. 

I think you probably need a degree just to understand the terms and how to measure them. But when you buy a pack of LED lights, there is huge play on the energy efficiency, a diagram showing you the output angle and the wattage. 

But Watts don't seem to appear any more in the calculations.

Some of the formulas include making sure that the diameter of the beam angles is equal to or greater than the distance between light fixtures. There are times when I wish I had paid more attention to my geometry master at school!

So I settled for the easy and practical option. I got one of the ceiling lamps out of the store, together with a bulb, a switch and some cable and jury rigged it, then waited for nightfall, by chance the night of the New Moon, and actually measured the light spread with a tape measure on a blank wall.

​It doesn't help that the room I am planning the lighting for, I can't really access at the moment, because I am using it as a store, until I get somewhere else converted to storage (the building permission problem again!).

I did find some useful information on one website, telling me I need to consider the size of the room I am lighting, the number and distribution of the light fittings, the ceiling height, the actual LED's I am using and my desired level of ambiance. The latter can of course be adjusted with your beverage of choice (from the Konoba), in a long stemmed or short fat glass, on a table. So I am back to tables again!

The packet the LED bulbs come in does provide some help. There are symbols all over, which tell me the bulbs give off 345 lumens, they are 5.3 watt and 36 degree lamps. 


So I now have the first figure for the calculation "The Angle[36] x .018 x the distance = the spread".

But it was the real world trial and measure which actually provided me with the information for the table and the data to draw a scale plan to fix where the holes for the wiring need to go! Sometimes the real world is better than all the theory!

I never fail to be amazed by the apps which are available now, and a search for "light meter app" on the android store - I don't have an Apple to my name - came up with a lot of different options.Before I install any app, I look at the ratings, how many downloads there have been - it's no good having a rating of 4.5 if there have only been 20 downloads - and then there are the actual comments as well. 

I downloaded Light Meter 2.6 by Borce Trajkovski and it works very well. These apps use sensors that already exists in your mobile devices, primarily the one which adjusts the screen brightness according to the time of day. So the apps will only work on the screen side, not using the rear facing camera.

Accuracy is stated to be about 95%, but no longer possessing a photographers light meter, I can accept the minor inaccuracy.

With the light set up on a stand at 2 meters from the wall, it was clearly too close, so I moved it back to three meters, and was then able to identify the spread of the light output.

​This led me to another train of thought. The ceiling is sort of at 90 degrees to the walls, the walls are 2.37 tall and the width across the room is an average of 5 meters (yes, the width does vary, by up to 300mm) so unless the lights are offset, then I can't get them in the middle. Knowledge of triangulation was required!

This is where I again wished I had paid a little more attention to the maths master in school. Trigonometry was not one of my strong subjects. I could understand Pythagoras, but I have to say that even doing crash investigation, it is only now, some 45+ years after escaping from school, that I have actually had to use the knowledge. And then I found a much easier way - a website where someone else has done all the hard work and you just enter three items of information, an angle and two distances and press [calculate] and it does the rest.

So after puzzling and working for a couple of days this week on the problem, including drawing scale plans of the room and some real world tests, I have the answer - 42.


​And as every intergalactic hitchhiker knows, this is the number from which the meaning of life, the universe and everything can be derived. So I actually knew the answer all along, only I didn't know it was the answer, if you see what I mean..... 

If you need to know more, just look at H²G²!

I think I should ask HAL where to position the lights... or perhaps Zaphod Beeblebrox.

On Sunday I was awoken by some distant thunder and lightning, a little before dawn. 

I had been aware of the potential for a storm because of the unstable atmosphere, but sadly our wish for rainfall did not materialise. There was not sufficient to register on my rain gauge, just a few drops on the concrete, which soon evaporated, but it has heralded a change to cooler weather with temperatures this week only reaching +30ºC and falling overnight to +20ºC.

While I was watering this week, I spotted another type of Katydid,
​and my water spray onto the young Avocado trees disturbed some recently hatched tiny Preying Mantis nymphs.

I have not seen young Mantis this late in the year before and suspect it is another result of the strange weather caused by climate change we have all been experiencing.

I am not sure if there is sufficient time for them to go through the molting process, reach adult size, mate and lay eggs, before the cold weather kills them.

We have had another large forest fire on the island, this time on the Kabal peninsula, the beautiful wilderness area at the very entrance to the Stari Grad fjord.

I smelled the smoke in the late afternoon and there was some ash falling, although I am 9 kilometers away.

​The military fire fighting squadron deployed two helicopters with Bambi Buckets to drop water on to the difficult to access areas, in support of the local fire brigades. 

The fire risk is still severe and will remain so until there is some sustained rainfall. The problem of course is that the build up of detritus on the ground in the Maquis and forested areas continues, and year by year it gets deeper, as it is not possible to clear it all away. It is only fire that will do that.

Saturday has NOT gone according to plan! 

I came home after a trip into town for coffee with friends, and to check on the progress of my timber flooring, turned on the computer and got a windows boot error message. 

It has taken me 5 hours to reinstall Windows 10, but without any of my usual programmes, so some of the graphics and photographs I had planned to use this week are absent and some of the ones I have included seem to have developed a will of their own to display different ways up!

I can see that the rest of the evening and probably most of tomorrow will be spent in trying to get back to a normal service. Oh joy!

It's the 42nd Faros marathon this weekend - good job I hadn't planned on taking part...

Norman