Light-box follow-up

Here is a quick long follow-up on my light-box construction post, which garnered unprecedented attention - thank you for all the comments!

When I set out to build the light-box, it was a spur-of-the-moment decision on december the 23rd. And let me tell you, buying something at IKEA on that day gives you a disorder all on it's own. I did not have much time for research, so I read a couple of webpages and set off. Now that I have a bit more time, I searched and found more information; here is a quick summary:

• Light therapy has been shown effective in numerous clinical trials since the 1980s (Lewy et al. 1982, Rosenthal et al. 1984 being the first)
• According to most studies, 5000 lux-hours/day give the best clinical response, 10000 lux for 30 minutes is most commonly used in practice. Note that I am talking about lux here, i.e. luminous flux, or lumen per square meter. The luminosity of light bulbs is given in lumen, which is the total light output in all directions. When building your lightbox you want to focus that in the direction of your patient. I used aluminium foil as a reflector, as a few commenters have rightly pointed out, a flat white coat of paint would have been more efficient (and would probably look better). Something to bear in mind for the lightbox Mark II.
• Light colour: Numerous studies have been done concerning which colour of light to use (Brainard et al. 1990, Lam et al. 1991 and 1992, Oren et al. 1991, Steward et al. 1991). Some found that green light was better than red one, and white light superior to yellow light, while others found no difference in efficacity. All agree however, that all light colours do have an effect. I went with soft white light bulbs, because I wanted to be sure to avoid UV.
• UV: There was a series of studies by Lam et al. (1991 and 1992) that first reported that white light with UV was superior to white light only, but a follow-up study by the same guy with a larger group of subjects found no difference. I think it is better to avoid shining too much UV into your eyes.
• Cost: A commenter asked me about the total cost of the project. I did not keep my receipts, but this is more or less what I paid (Sister, if you are reading this - skip the next paragraph!):
  
  *) 10 23W Philips CFL spiral light-bulbs: 80 Euro
  *) IKEA Mackis box woth lid: 20 Euro, but since this is a set of three boxes, you have the two smaller ones left over
  *) 10 bulb holders, switch and cable: about 20 Euro
  *) Aluminium foil, wood and construction glue: Free because filched from my parents
  
  Which gives a total cost of about a 120 Euros.

Most of the information above is from the book

Seasonal affective disorder and beyond light treatment for SAD and non-SAD conditions: Light Treatment for Sad and Non-Sad Conditions
By Raymond W. Lam
Published by American Psychiatric Pub, 1998
ISBN 0880488670, 9780880488679
Here are the relevant pages for your perusal (thanks, google book search!):












Bibliography:
Brainard GC, Sherry D, Skwerer RG, et al.; J Affect Disord 20:209-216,1990
Lam RW, Buchanan A, Clark CM, Remick RA; J Clin Psychiatry 52:213-216, 1991
Lam RW, Buchanan A, Mador JA et al; J Affect Disord 24:237-243, 1992
Lewy AJ, Kern HA, Rosenthal NE, et al.; Am J psychiatry 139:1496-1498, 1982
Oren DA, Brainard GC, Johnston SH, et al.; AM J Psychiatry 148:509-511,1991
Rosenthal NE, Sack DA, Gillin C, et al.; Arch Gen Psychiatry 41:72-80,1984
Steward KT, Gaddy JR, Byrne B, et al.; Psychiatry Res 38:261-270,1991

Fun with Chiles

Receipe for hot & spicy fun:

Take some chilli con carne or a similar dish. Season very mildly, explain to your friends that you "can't season it properly because you are a bunch of sissies". Put a glass of whole, dried chiles on the table, for "those who want some real flavour." Serve, and watch carefully as people use their fingers to crush the dried chiles. Then tell everybody to "take care not to touch their eyes now, because it $%&^@ hurts!". This seems gnaw at ths subconcious, because not soon after somebody will touch their eyes, or pick his nose.
Lean back and enjoy the ensuing hilarity, especially when people laugh tears at the first unfortunates and then proceed to wipe those away...

For an encore tell everybody to take care when visiting the toilet...

The godess of cats accepts your devotion

But there is no need to be so loud and vulgar in your devotion. Please, grovel silently.

Lightbox Construction

Yet another update (01/16/2009): It worked! My sister reports feeling much better.

Update: For more facts & numbers, see my follow-up post here!

My sister suffers from seasonal affective disorder, also known as winter depression. A commonly prescribed therapy is light therapy - about thirty minutes of bright light in the morning. Bright in this context means more than 10 000 Lumens. You can of course buy commercial light-boxes, but I wanted to construct one by myself...

Behold, the DIY receipe for your very own Lightbox!


You will need:

• A load of  light-bulbs - I used ten 23 Watt flourescent bulbs which were advertised as the equivalent of 130 Watt incandescent bulbs. Anyway, we are interested at the amount of light they put out: 1560 lumens each. The light colour does not seem to be very important, according to the literature dealing with S.A.D. - just avoid daylight bulbs that emit UV.
  
  
• A box - I used a cheap Ikea Mackis plywood box. It's height fits the bulbs I choose perfectly, and you can get up to twelve of them into it. Above to the right you can see where I tried to figure out the placement of the bulbs.
   
• Bulb holders and cable and a plug - the cheapest ones, the holders won't get very hot.
   
• Some way to drill the holes for the bulb holders into the plywood. I used a drill that is meant for use with floortiles. Not perfect, but it worked.

After you have figured out the placement for the bulbs, drill the holes into the bottom of your box. It is not necessary for them to be very neat, since they won't be visible afterwards.

Then find a way of making the interior of the box reflective - if you are cheap and lazy like I am, a bit of aluminium foil will do. If you are awesome, you could drill holes in mirrors or something.

Next on: fitting of the bulb holders and cabling. Use some non-shrinking adhesive to secure the holders - I used "Konstruktionskleber", you could use silicone as well, I guess, or some epoxy. Then you want to connect all of those bulbs in parallel.

Here cabling is finished, and the first test has commenced. After thirty minutes the air inside the box was warmish, but in no danger of overheating and melting the bulb-holders or setting fire to the wood.

When the box is operational, and you have checked your cabling for short-circuits waiting to happen (exposed leads and so on) , it is time for cosmetics, i.e. hiding all the cables from the casual eye (and from not so casual toddler-hands).

Simply glue the top of the Ikea box on the back - if you have measured and planned carefully, all those cables should have place beneath it. If you haven't, it is time to curse and get out something you can use as spacer. I was lucky, though: everything fit.

And here it is, in all it's glory:

Yes, it is bright. Flee, oh demons of depression! Flee the holy light!

Christmas Haul: Coffee Grinder

My sisters, who may just be the most wonderful sisters in the world, not only read my blog, but noticed that in this post, I bemoaned the lack of a proper coffee grinder in my household.

Behold: His Grindingness!

Ohh, the smooth uniformity of the grind, the steady, unyielding churning of the crushing mill, the elegant simplicity of the mechanical timer, which eschews all unnecessary electronics...

Excuse me, I think I am going to have another coffee.

A harmonious Christmas

They are only playing.
Really.

On the road

Today I am on the road, nearly a thousand kilometers back to my parent's in Kaltenleutgeben, near Vienna. Here is a photo of my car-battery for your amusement. It is sitting on my floor, slowly charging on my pitiful 750 mA charger, because it went flat out of scorn for my neglect: In winter it pays to actually use your car from time to time, even if you'd rather take your bike to work.

Preparing the Plants

... for two and a half weeks absence. In the summer I tried to go with bottles of water connected by strips of cloth. That strategy backfired, capillary action failed me and my little palm-tree nearly died.

It is still not entirely recovered - as evidenced by the sad brown leave on the right. The farn and my Ficus benjamina (cunningly hidden behind the Elephant's foot, which is doing very well, thank you) are also ailing yet. So this time I am going with the humid-bathroom method, the well watered plants above a few centimeters of water in the bath-tub.
Should be alright, especially since there is no light, and the temperature will be around twelve degrees .

Back from the pit

A sudden urgency overcame my resolution to post (semi-) daily last week: The dreaded annual report. But now it is done, behold:

 

No, this isn't some innovative new form of writing your report, this is a worlde of the fifteen-page monstrosity I produced. Which I had to cut down to six pages afterwards, because (as I learned) this is the upper limit for annual reports at the EPFL. Figures. I'll put up the whole thing to read here as soon as I have finished finnicking that last graph.

Rings & Riches

For yea, his hand doth overflow with the riches of the earth...

I got more Macor-rings from the workshop today. They made me promise that I would take better care of them this time, because they are expensive and hard to machine - so I lied and said yes.

I guess I am just evil that way.

Gobi desert

Nothing to say, have a photo instead.

Taken with my old Minolta Z1 from the transsiberian railway, back in 2005. ISO 50, f/3.5, 1/125s, 38 mm equiv.

iBrick Mk. II real world performance

About two weeks ago I built the iBrick Mk. II, an external battery for my iPhone. I calculated it's capacity to about 5000 mAh @ 5 V, assuming eight 3000mAh NiMh rechargeables. This would mean an extension of the iPhone's battery life of around a factor of four.

Unfortunately I did not have eight 3000mAh batteries - those buggers are expensive! So I had to made do with six 2500mAh and two 1200mAh accus,  sub-optimal since you shouldn't mix capacities. To make up for it, I gave the iBrick the iBrushed-Metal upgrade, which you can see on the right.

On Saturday morning I charged both the iBrick and the iPhone completely, and used the former exclusively to charge the latter until both ran out of power on Thursday morning. Normally my iPhone lasts me about a day and a half, so the iBrick lasted for around three and a half days, or a bit more than two complete recharges. That looks promising,  and yesterday I bought two more 2500mAh NiMhs, so I can see how much the low-capacity ones dragged the rest down. Stay tuned for more exciting updates about the iBrick!

In the ball-park

On the ninth of October I bemoaned the fact that I'd have to redo nearly all measurements of 2008, due to a nasty reasonance that changed the voltage I was measuring by a factor of 2 to 10, depending on the setup. I said it would take about two to three weeks.

Ha!

It is only now that I have really figured out what was going on, and finally have redone the most important measurements. and this time I am sure, because lo and behold:

The red curve is mine, the rest of the graph is from Lisovskiy and Yegorenkov: "RF breakdown of low-pressure gas and a novel method for determination of electron-drift velocities in gases", Journal of Physics D: Applied Physics, Vol 31 (1998), p 3349-3357. Not exactly the same curve to be sure, but that is to be expected, especially since he used stainless steel electrodes, and I use aluminium ones.  

Totally different ion-induced secondary electron emission coefficients, dude.

Small bruise

In the spirit of total disclosure, and also to show all the girls out there how incredibly tough I am (you have my email, ladies ;), I have to amend yesterday's post. It seems that I have, in fact, sustained a small bruise on the knuckles of my right hand, which I did not notice until this morning. This illustrates that when you punch somebody, you really should take care to hit only with the first two knuckles of your hand (index and middle finger), which are much tougher.

There, now you have learnt something today. Punch away with confidence.