Thursday, June 30, 2022

What can you see with a 60mm telescope?

Like every other geek, I love astronomy and most things related to space. I never truly pursued this topic, apart from the odd article on NGS, but now I get to use a telescope on the weekends. The telescope ain't that much, but it ain't that bad either. It's a 60mm Konus, with equatorial mount and a motor (which basically means I can point at an object, turn on the motor and the motor will make up for Earth's rotation). One of the things I would like to know is what can you see with such a telescope. Oddly enough, I still wasn't able to find a comprehensive list on the net... so here's what I was able to see so far: (I've only used the telescope 3 times, so I hope the list will grow in the future!)
  • Moon: Excellent view, great contrast on the craters. I plan to look at it with a lot more detail.
  • Saturn: I was able to see the rings without a problem. I still wasn't able to see the Cassini Division, but I'll keep trying. I was able to see a bit of the texture of the planet, but it's mostly a small white ball. I was also able to see one of the moons of Saturn (Dione, I believe).
  • Mars: I've seen it without much detail, because right now it is way up in the sky and therefore a bit uncomfortable to watch. Still, it is rather small, and the only detail I was able to see was that it was only partly lit by the Sun.
  • Orion Nebula: You can see the trapezium cluster without a problem, as well as the nearer 3 stars. But the nebula itself is rather faint, and you can only see the brightest part. And even that is only a small blur.
Next, I plan to see the Sun (I'll need to buy a filter), Jupiter and some other Messier objects. (I'd really like to see the Whirlpool Galaxy, but I still wasn't able to spot it... don't even know if it is visible with my telescope!)

Beryl: Desktop Fireworks

If you want to make your Ubuntu desktop really come to live, Beryl is the answer. It's an accelerated OpenGL desktop manager that gives you a lot of bells and whistles visual feedback on your window manager operations. Installing is not as simple as you might wish, but it isn't too hard either. On the Beryl wiki there's an entry on how to install Beryl on Ubuntu and you can basically follow that. The only notes I have on the installations steps are: I had an error message while starting Beryl. As a consequence I had no window manager! The message was:
beryl: No GLXFBConfig for depth 32
After doing some searches on the web I found a post that gave a solution to this problem. Just add the following to "Device" section on your /etc/X11/xorg.conf file:
Option "AddARGBGLXVisuals" "True"
Option "DisableGLXRootClipping" "True"
Also I skipped the entire "Configuring Beryl" section and just added beryl-manager to my Startup Programs in System > Preferences > Sessions Next you have to configure Beryl. There's a ton of options, animations, keyboard shortcuts, themes, etc, etc that you can tweak with to make your desktop look exactly like you want it to! And if you have a bit of patience and 28Mb of spare memory to run Beryl, it's really worth the trouble.

Tuesday, September 16, 2014

Building a mobile agenda for JSConf

[Update: Sorry for the missing pics... Deleted by accident. Thank you google...]

A couple of OutSystems' engineering guys were going to a JSConf Europe conference this weekend. While looking for the schedule, they found this:


We just couldn't let this opportunity go by, so João Neves used Platform 9 (which is about to be released) to build an agenda for the event. You can find the application here. It gets the Agenda from google docs using the new REST capabilities, and it is a completely mobile ready!

And, since on the week before I was playing with the source code of OutSystems Now, I built an application for Android that would allow attendees to view the schedule of the conference on their devices, even if offline (source code here).

The results were pretty cool! At the time of writing, 125 people had installed the Android App and we a bit over 7.500 pageviews! And we had some good reviews! :)

    


Saturday, April 26, 2014

Star Wars stop motion

Some fun with the kids, using discount animation software (the movie is in Portuguese...):


If you're curious, we used iStopMotion to record the video using an iPad camera, ToonBoom to add the lasers, QuickTime to record the sound, and iMovie to assemble everything. Extra videos and sounds downloaded from the internet.

Sunday, February 23, 2014

Displaying discrete data in R

Suppose you have a restaurant, and you do a survey where your customers can grade from 1 to 5 several aspects of that restaurant. The 1st 5 lines on your data will look something like:

Food Drinks Location Service
1 4 2 5 5
2 4 3 5 4
3 5 4 5 4
4 3 3 5 4
5 4 2 5 3

To analise this data, what I would usually do is check the mean, standard deviation, maybe do some histograms, and maybe do a boxplot of the data.


But when you have small amounts of data, these approaches tend to hide the story. An alternative option is to use a beeswarm chart:

This type of chart shows the entire dataset, allowing you to see everything at a glance!

If you're using R, you can create these charts using the beeswarm package. You can find the code that built this chart here (it also uses the reshape package).

Tuesday, December 31, 2013

Circular Menu with D3.js

WheelMenu is a circular menu aimed at mobile that allows you to quickly select from a small set of options quickly and with your thumb. You can see an example of the WheelMenu running in jsFiddle.
Right now the menu only works for 6 slices, but let me know if you need other number of slices.

Check the github page for more details on how to use the WheelMenu and for access to the source code. If you're using the OutSystems Platform, head over to the community and download the component.

Credits to the WheelMenu original design go to Tiago Simões and Daniel Nobre.

Sunday, October 6, 2013

D3 drag and drop tree

I needed a heavily customizable drag and drop tree and I couldn't find one that really fit my needs, so I built one. It was also a great excuse to learn about D3, although most of the work was messing with the quirks of drag and drop.

Anyway, although the code is far from decent and the tree is still work under progress, I decided to make it available to whomever wants to use. I hope it's useful for you, and be sure to let me know if you have any problems.

More info and download at github!