Thursday, May 26, 2016

Choosing a koganmobile plan

Recently Kogan Mobile started to offer a great variety of plans. They all have unlimited calls and sms (except for the standalone data pack) with differences in monthly data allowances. The general idea is that the more you pay up front, the better the value that you get.

It can be difficult to figure out which has the best value for you. My monthly usage is about 1.5GB. Here is a chart with what I believe looks like a good balance of spend commitment and value showing in cyan.

Monday, May 23, 2016

LED strip wall painting backlight

Installing an LED strip behind a painting hung on a wall creates a nice effect that highlights the artwork, as well as providing a soft ambient light in the room. You can get the parts via ebay for about $10 to $20.

It is important to offset the painting from the wall, so that the LED strip has a place to sit as well, and has sufficient space for the light to leak out.

On the back side of the frame, install 4 screws at each corner, about 1 inch from the edge of the frame. Leave enough of each screw end to string the strip around it (about 10 to 15mm depending  on the screw head and any loose canvas that my interfere). Finetune the screw lengths by hanging the painting, pressing on each corner in turn and checking for a wobble. In a way the whole assembly should be like a table with four legs -- it should not wobble.

Secure the LED controller module and 12V power cable so that the power cable exits the frame on the lower middle edge, to go to the power supply plugged into the wall. You can use safety pins and attach to the loose canvas at the back that had been wrapped around the frame, or any other means available. You need to have enough tension for the strip so that the lights point outwards. This can be done by securing the power end to the frame, going around the screw corners and setting up a small loop at the other end by using the adhesive backing. You don't want too much tension (as that can damage the strip), or too little (as the light may not be uniform). It is important to cut any excess LED strip length in a suitable place (in this case I only used about 3m out of the original 5m strip).

Saturday, May 21, 2016

Friday, May 20, 2016

DIY 18650 battery hack conversion

The great reason for adapting 18650 batteries to work with your everyday gadgets is this:
In my humble opinion, I think 18650 batteries are an awesome upgrade to the humble old timey AA. They charge much faster, hold more energy, and in recent years had become super affordable at something like a dollar a piece. If you are reading this on an average laptop then there are probably three of them inside it -- try doing that with AAs!
IMPORTANT: 2xAA ~= 1x18650

To get started you will need:

This is going to be a growing list of gadgets to which I applied the 18650. The results are not pretty but this is not called fashion either:
  • Photography flash trigger (originally 2x AA, replaced by 1x 18650) and receiver (originally mini 12V, replaced by 1x 18650)
  • Speedlight portable flash (originally 4x AA, replace by 2x  18650)
  • Hair trimmer charger (originally a proprietary wall-wart with quite a long cable, universal AC to 3.7V, replaced by 1x 18650)

Thursday, May 19, 2016

speedlight speedlite flash 18650 lithium battery hack

In my humble opinion, I think 18650 batteries are an awesome upgrade to the humble old timey AA. They charge much faster, hold more energy, and in recent years had become super affordable at something like a dollar a piece. If you are reading this on an average laptop then there are probably three of them inside it -- try doing that with AAs!

It is baffling why camera gear manufacturers haven't adopted 18650 batteries yet. You can find 18650 in everything now, from Tesla cars to high power flash-lights, USB power banks, and most laptops. My friend pointed out that the average photographer doesn't like change, had to be dragged kicking and screaming to convert their workflow from film to digital, and AA is something that they understand.

Recently I tried to find evidence that hands-on DIY MacGyver type photographers are using 18650 with their flash units and cameras only to find an unconvincing adaptation of the idea, or reasons against it (this had to do with maximum available current, which is contentious depending on who you ask).

I had to try it for myself, so I ordered some 18650 battery holders from ebay.

My initial conclusion is: SUCCESS. It seems to work just fine. What you see here is not pretty but it works. No doubt future iterations will expect to look more glamorous and more resilient to work in the field.

Yes, there is a major current train during capacitor charging, but it lasts for only about 2 seconds on charged batteries on maximum setting (1/1), while a blink of an eye on minimum (1/128). After a few cycles of maximum discharge you can feel the batteries get slightly warm. On a real shoot one would be swapping out a stale set for a fresh set as needed, and not wait to run the batts into the ground, so I'm sure this will work out just fine, and you can pack a lot more power now.

Here is some voltage readings. The low blip is just after a full power flash went off.

Will update this post later, when there is new information.

In the next iteration removed most of the rubber bands

Tuesday, May 17, 2016

Hello World via Google Cloud Platform

No, this isn't strictly speaking Ubuntu related, and is at best most general regarding web servers. However my new tech toy is Google Cloud Platform used to set up a web server to operate a landing page. I have been putting this off for too long, but finally got my toes dipped. Opted for the free trial, you should go for it too, but don't waste it.

Here is a primer, but I did not have time to watch it yet:

Here is on how to make a LAMP stack, but I stopped at LAP:

Here is the cockpit:

Here is on uploading files to your new server, which took me 90 per cent of my initial setup time until I figured out what's what:

Once it is running and you just changed config, remember to restart
sudo /etc/init.d/apache2 restart

Made a landing page:
I wonder how effective would it be to operate without a domain indefinitely.

Update: upgraded the ip url to a domain url,

Friday, May 13, 2016

VLC audio tape record notes

Here are some notes on how I transferred my friend's tape to mp3. VLC gives you a WAV file. I used kdenlive to make a project and export it to an MP3 file. The WAV keeps all of the hiss as it comes from the tape; exporting mp3 at q7 takes the hiss out; mp3 at q10 keeps some of it and other subtleties if you need to preserve them).

Friday, May 06, 2016

No Carriageworks

Ever since I discovered Carriageworks, maybe in 2012, I loved it. It is a local institution. It was one of my favourite places to visit in Sydney and I recommended it to everyone who would listen. In the previous two years we even had a double membership to Performance Space (which is in the same place), which proved to be of mixed value but that's another matter. Carriageworks had maximum available goodwill and my five star rating. And so it baffles me that in the blink of an eye it landed on my shitlist and was reclassified as To be Avoided like a wet blanket.

How this situation came to be had to do with a random visit on a quiet Autumn afternoon, Friday 6 May 2016. Days earlier I got what seemed like a good idea, that is to take a few snaps of walls and floors for later use. That sort of material can come in handy randomly for creative retouching projects. When I got there, the place could hardly be more quiet -- the few staff and volunteers on duty easily outnumbered the few and mostly out of view visitors. For the 10 minutes that I was there, nobody was bothering anybody, until I got pulled up and told to stop.

Of course the poor lady tasked with approaching me was just doing her job and expressing policy, but this shines a light on the bureaucracy, leadership and internal culture. It gets a finger wagging, and the sentiment of my offended sensibilities will be noted and offered to others.

It follows that I unpublish all my user generated content posts associated with the place. As yet I had not decided on how to deal with my new boycott, but paid work associated with the location shall pass. I mostly resent this sort of thing because it renders all past time spent here as a total waste of time and energy. Had we foreseen the outcome, we would have avoided it in advance.

I know that in the scheme of things none of this matters but if you piss us off we hold grudges, and shun. There is no scarcity of better things to do with our time. Nobody needs this.

I'm curious how long this grudge lasts before I need to undo it.

Thursday, May 05, 2016

Chairman Mao (3)

Spicy pickled cucumber
Stir fry cauliflower with cumin with chilli
Stir fry leeks with five spice bean curd and chilli
Xiang Quan / fine spirit from Hunan Province