This is the archive for Tech.
- Light temperature, Sleep, and F.lux
I posted again over at The Primal Challenge today. Here is the post, in its entirety, below:
I don’t know about you, but the “no glowing rectangles an hour before bed” rule is difficult for me. At Hillsdale I am usually so busy that I can’t avoid using my laptop before bed, lest work go unfinished. That used to affect my sleep a great deal, but then I came across a tip in Matt Madiero’s book, Roots.
Matt recommends a great piece of freeware called F.lux. Made by Stereopsis, F.lux is a free, cross-platform (Windows, Mac, and Linux) piece of software that changes the color temperature of the screen on your computer at night to the ambient light around you. Normally, screens are set around 6500 K, roughly the temperature of sunlight, which is great for waking you up, but not for allowing you to fall asleep. Some CRTs go all the way up to 9300 K. F.lux changes your screen temperature at sunset to around 3400 K, which is roughly the temperature of halogen light.
When I first installed the software, I didn’t think it made a noticeable difference until I turned it off a few hours later in order to edit some photos. When I turned F.lux off, the screen hurt my eyes! I can’t definitively say it has improved my ability to fall asleep since I’ve used it because I am getting more exercise during the day and I am usually exhausted by the time I go to bed, anyway. Since turning it off hurts my eyes so much, though, I suspect that f.lux is at least not hindering my brain from making melatonin to make me sleepy.
Stereopsis cites a lot of research which deals with the effects of color temperature. Here is an excerpt:
“…we surmise that the effect of color temperature is greater than that of illuminance in an ordinary residential bedroom or similar environment where a lowering of physiological activity is desirable, and we therefore find the use of low color temperature illumination more important than the reduction of illuminance. Subjective drowsiness results also indicate that reduction of illuminance without reduction of color temperature should be avoided.”
- from the paper: “Effect of Illuminance and Color Temperature on Lowering of Physiological Activity”So, does this mean it is okay to use your computer all of the time before you go to bed? No. It is still best to keep things pretty low-key and dim before you go to bed. You should also avoid having lights in your room at night. (I covered up all of the lights on my gadgets.) When you must use your laptop at night though, lower the color temperature with F.lux. Also, if you are the type of person who reads for an hour before bed, use a bulb with a lower color temperature. Wikipedia has a good chart of common bulb color temperatures.
Want to know something interesting? Those most of those curly florescent bulbs that Congress is trying to get you to buy are around 5500 K. So not only do they contain mercury and are more expensive than incandescent bulbs, but they are also ruining your ability to fall asleep. As Bastiat noted so long ago, government intervention has unintended consequences.
- Day 244 – Snow Leopard
Click on the photo to view it at a larger size:
I installed Snow Leopard the day after it came out, since I was on a retreat in the middle of the woods when it was shipped. I can tell a major difference in how fast my computer processes and exports photos, and I like the new Expose and contextual menu layouts. The upgrade was definitely worth $30.
I start classes tomorrow!
- Day 234 – Ashland / Palm Pre
This morning/early afternoon, I went to Ashland with HankD and Jackie to go to Fin Feather Fir Outfitters. While in Ashland, we stopped at Ashland University, where Jackie went to college. Above is a photo of one of the buildings on campus.
A note on my Palm Pre: I found out today that it is possible to put the phone into developer mode and install third party apps. My Pre just got 20x better! This is wonderful, as the Palm App Catalog is still in beta form, and has very few apps. Visit PreCentral.net to see how to do it.
As of right now, I have a Google Voice app, a better Twitter client, a DOF calculator, a tip calculator, a scientific calculator, a unit converter, a Google Mobile web apps launcher, an iTunes remote, an IP address revealer, a flashlight app, and a quick dial application installed.
- Day 230 – Palm Pre
I got a Palm Pre! I’ve only had it for a few hours, but I really like it. I will write an in-depth review in a few days, after I’ve had time to find the ins and out of it. For now, here is a low quality photo of it charging on the touchstone:
- Day 218 – Google Voice
My Google Voice account got activated! (If you do not know what a Google Voice account is, visit http://voice.google.com/.)
My number is: (440) 941-7247
Call, text, or leave me voicemails!
- Day 204 – Major Photo Edit
A few years ago, I did a major photo edit for a lady in my school district. The original 4×6 photo had 5 people in it, and she wanted the guy on the far left taken out, but there was a problem: the guy next to him had his arm around him. So, I spent about two hours putting the guy’s arm back in and fixing the back ground. Click on the image below to see the before and after at a larger size:
- Day 188 – More Kayaking & Misc.
I have only had my kayak out four times since I bought it a little over a week ago, but I am really enjoying it! I took it out tonight at the Wellington Reservation. Here is the view from where I sit:
Since I used my Dad’s camera to take the above photo, I found some pictures of me on it that he took down in Tennessee. Here is one of me in the hat I bought to keep the water from my paddle from dripping on my head:
Now for the misc. part:
I found two free cool Mac apps over the past few days: Adobe Kuler and The Unarchiver.
Adobe Kuler is actually an online application, but it has an Adobe AIR desktop plugin, so it has a nice desktop application. Kuler lets you browse, create, and download color schemes. You can import them straight into Photoshop or Illustrator. You can even create color schemes from photos! This is a must-have if you are a designer or artist.
The Unarchiver is an unarchiving utility. Yes, your Mac comes with one preinstalled in the system, but this one is better. It supports 30+ file formats, including some pretty obscure ones,and it can handle filenames with foreign character sets.
- Day 187 – HTML 5
As many of you already know, HTML 5 was released a few days ago. Say goodbye to XHTML! (Finally!)
Here are a few resources for those of you who want to get an edge on the competition and see what is new in HTML 5 so you can implement it right away:
Also, here is a PDF cheat sheet from Smashing Magazine. Click on the image below to go to where you can download the full PDF:









