Time Lapse Photography using Smartphone (Part 3 - Tools you need)

Regardless whether you are using Android smartphone or Iphone to take time lapse photography, there are several must have items you need in order to take the photo successfully... Let's take a look at what is available and what others have done.

1) Smartphone holder

Off the shelf products	Options	Image	Notes
1) Tripod	a) Standard full size camera tripod		Large and heavy
	b) Mini Tripod		Small and light
	c) Mini-flexible Tripod		Small and light
2) Smartphone holder with tripod mount	a) phone holder with tripod mount		Small and light. Only suitable for phones with width of 4.5-6.2cm.

2) Power supply

Unless you are only looking at taking time lapse video with less than 300 photos/frames over a period of 2 days or less, you basically need to hook up your smartphone to a power source to make sure that it do not run out of power during its photo capture.

a) Wall outlet charger: If you have a power outlet nearby, it is best that you use the wall outlet charger that comes with your phone. This is only suitable for indoor use, do make sure that you make it water proof if you use it outdoor or else you will likely cause short-circuit and damage.

b) External battery: If you don't have a power outlet nearby, you can use an external battery to charge your smartphone. There are plenty of external battery packs around in the market that provides 5V USB power. Make sure you buy the one with the largest capacity or do your own calculations to see what much extra power you will need to complete your time lapse video.

Based on the previous article's battery life test results, if you are using a HTC G1, configured to take photos at 60 seconds interval, with GPS turned off. You are looking at current drain of around 220mA. This means that even the largest external battery available, rated at 10,000mAh will only last at most 45hr. Taking into account of the HTC G1's internal battery, you will only get around 50hr, slightly more than 2 full day's of battery life.

If you are using external battery to keep your phone charged, you will likely need to have at least two of them and you will need to change it once per day.

To see if my prediction is correct, I have re-run the earlier battery test on my HTC G1 while it is connected to a 10,000 mAh external battery pack as its power supply, also using 2Gb microSD with the parameters and results below. Everything is done in the same way as before except that in this test, I have also installed Air Droid, which I used to remotely monitor the phone periodically by looking at the date stamp on the photos in the phone's microSD card to make sure it is still running, instead of turning on the screen to check it. This is to mimic real world condition because you can't really go and turn on the phone's screen to check it all the time....

Unfortunately, the results is worse than expected. With a 10,000mAh battery as the phone's power source, the phone was only able to last up to 37 hours regardless of the settings configured. Considering that 10,000mAh external battery is about the largest capacity battery you can buy off the market, this means that using an external battery will only give you at most 2 days worth of photos. If you are going to take many days of time lapse photgraphy on your smartphone using external battery, seems like it is inevitable that you have to change the external battery every 24-36 hours.

c) Solar panel: If you are taking your photos outdoor, it is reasonable to assume there would be plenty of sunlight. Therefore, using a suitable solar panel supplemented with a rechargable battery would be more ideal since the sun can provide "unlimited" supply of power for the smartphone.

There are many solar panels in the market but the power rating on most of them are very low, at around 0.4-0.7W, i.e. only able to provide around 80-140mA current. As evident from the previous battery life test, this level of power output is insufficient to sustain the power drain (>220mA) from the smartphone at all even though the power can reduce the drain on the battery pack.

As the battery life test shows, you will need a solar panel that can provide more than 1.1W (220mA) of power in order to prevent battery drain. Taking into account the power lost during battery charge/discharge as well as the assoicated electronics circuitry, it is reasonable to require solar panel that can supply at least 1.4W of power in order to keep the external battery charged during the day.

Taking into account that the sun only comes out in the day and you need to rely on your battery pack at night as well as during overcast days, it is reasonable to assume that you will need a solar panel that can provide at least 2.8W of power in order to charge your phone as well as your external battery pack during the day. Unless you are prepared to swap the external battery once every 24-48 hours for charging.

3) DIY outdoor time lapse photography holder/stand

If you are taking your shots outdoor, then you obviously have more to consider. The most important would be to weather proof your setup. Below are some DIY phone holders that others have made, with links to the guide.

Custom-made/DIY weather proof box (link)	Image	Notes
Time lapse enclosure for smart phones		not 100% waterproof but can reasonably survive rain
How to Make a Weatherproof Camera Box		Water tight container but the phone/camera may be subject to overheat under the sun

At the time of writing (Dec 2011), I don't see any shops that sells off the shelf weather proof box for smartphones, though there are plenty of water proof phone bags to protect your phone when swimming or playing at the beach. Since those water proof bags uses thick PVC, it will make it hard to use the touch screen.

Unless you are going to build your own weather proof box to house your smartphone, it is going to be problematic to take time lapse photography outdoors for days and weeks.

In the next article, we will look into the materials we put together that we believe would be suitable for outdoor time lapse photography on your smartphone. (If you are interested to buy the setup we make, please feel free to contact us. If you don't see the next article yet, it is because we are still working on it and we would be interested to hear your feedback or if you want to get one immediately.)