With the Seek Thermal camera you can finally measure the temperature of a surface with your smartphone, finally! Ok, maybe I am a little too excited, but this article will show how cool it really is.
In the past year, thermal cameras have had a sudden surge in popularity. The reason for this is the two rivaling companies (FLIR and Seek) releasing their thermal cameras in around the same time (July and September 2014 respectively). At that time, according to Google trends, the popularity of both thermal cameras started to increase. Interesting to note is that at one time FLIR Systems Inc. and Seek were actually friends at one point.
A little history
To appreciate how it comes that two thermal camera companies suddenly build thermal cameras, we have to go back in time and do a little research. In 2004, FLIR Systems Inc. bought Indigo Systems Corp. The company made technology used in FLIR thermal cameras. FLIR makes cameras for military and professonal use. Two executives at Indigo, William J. Parish and E. Timothy Fitzgibbons stayed in the company for some time, but eventually left and started their own company, Thermicon. In 2006, FLIR sued Parish and Fitzgibbons for negotiating with competitor who makes thermal chips called Raytheon Co. [gizmag]. The suit was for “misappropriating trade secrets”. FLIR lost the suit and had to pay $1.6 million in attorney’s fees and costs. [Oregonlive]. Then a couple of years later, in 2008, Parish and Fitzgibbons sued FLIR and won $39 million. Then they started Seek and the rest is history.
The two companies are experts in thermal camera technology and they use a different approach to thermal imaging. Without going into technical details, FLIR use a case that covers the lens of the phone. The thermal image is then fused with another camera which allows the user to get a “augmented thermal image” with pronounced edges from the ordinary camera. This makes it easy to see what you actually see. The FLIR also requires a separate power source (hidden in the case). The battery runs for 5 hours of continuous use according to the FLIR website.
The Seek [Seek] variety is simply a camera that is attached to the micro USB. The camera use the power from the USB and the visual feed from the camera that is already on the phone. When taking photos with the thermal camera (XR) the images from the camera and the Seek camera will not match as well as with FLIR, because of the longer distance between them. Also, the Field of View of the XR differs too much compared to the ordinary camera. This could possibly be fixed in software.
So, why did I choose the Seek camera? Well, that’s nice of you to ask sir or madam. There are a couple of reasons actually
- It is cheap as thermal cameras goes. It cost only $200 compared to FLIR $349 [independent]
- It has a higher resolution at 300×200 pixels compared to Flir’s 160×120 pixels
- It works for Android and Iphone, Flir only works for iPhones
Taking everything into account, I had to go with Seek. Please note, there is another company that sell a more expensive thermal camera ($939, special price as I wrote this) called ”Thermal-app”, but we will only focus on Seek in this post [Therm-App].
An interesting difference between Seek and Therm-App is that Therm-App works fine with Android 4.1 (Samsung Galaxy S2) while Seek require 4.3 (Samsung Galaxy S3 and later). I had a S2, so I had to buy a new phone, but I got a good price.
Tip: You can get the max/min temperature of whatever you are looking at with the camera.
There is an app for that
Yes, there are apps for thermal imaging without the camera, they have been part of the Android and iPhone for a time now (see Thermal Camera). The problem is that they do not work because they can’t really ”see” temperature, it is only a image processing effect. To be able to see temperature you need special IR sensors ([axis]) and a lens made out of chalcogenide glass (Seek has this) because ordinary glass will filter the IR so it never reaches the sensors. This is also the reason why you cannot see through a window using the thermal camera.
The choice of Seek or Seek XR
Seek has two versions and the difference is the field of view (36 compared to 20 for the XR) and the ability to see further. I chose XR because I wanted to use it outdoors.
So let’s show what it can do. First off, it is small and sturdy. When I attach it I always make sure to hold it firmly, because I really don’t want to drop it.
Tip: Disable “smoothing filter” and WIFI if the camera starts to lag.
To show off the thermal camera I took a few photos and videos with it. If you have more suggestions of interesting things to take photos of, please leave a comment.
The footprint is quite noisy. This is due to that the difference in temperature in the actual thermal print and its surroundings is very small, maybe one to two degrees at most. Another thing that might affect noise is thermal noise. That is when sensors react to heat from the actual camera. So a cooler environment will show up as less noise in the photos. I will investigate if this is a problem and how to use image processing to reduce noise in a separate post.
We can also see the absolute temperature (will save accurate tests of temperature for a separate post).
I filled a pot with cold water and poured in some hot water, just to see how it will mix with the cold water. Notice that the brightness suddenly change when the water is poured in. So, the camera dynamically change the brightness depending on the view. I would like to lock the color map so I can take the temperature afterwards. I will investigate the open source codes available to see if this is possible.
The photo of my thermal bodyprint in the beginning of this post reminds me of a movie with Laurel and Hardy called Block-Heads (1938). There is no reason for me to bring up that movie other than that and that it is a really funny movie.
Another use of thermal imaging (sort of). It is a classic scene from Ghostbusters (1984) when Ray Stantz, played by Dan Aykroyd, spots a ghost (Slimer). Note the thermal goggles on his head.
The affordable thermal cameras are not producing high quality images we are used to seeing with ordinary digital cameras, but one has to marvel at the fantastical super power it is to see heat. Remember, darkness does not affect the image quality. In fact, a warm body in the woods, in the middle of the night, will light up like a christmas tree compared to the cool surroundings. Also, the ability to code your own image processing using the thermal camera (if you apply to be a “Seek developer”), will make the community even more interesting. It is also a wise move, as it will most probably make it much more popular. If ordinary users can find creative ways to use the thermal camera with the sensors that are on the phone already. This is why am I excited about this technology.
At the present, the thermal cameras are still a novelty. There are only a few things you can do with a thermal camera at this point. I’m looking forward to the future in thermal imaging. When the thermal camera increases in framerate, resolution (in both pixels and temperature) and maybe even provide slow motion video. Think about the applications today and it will be reality tomorrow.
This is a “review”, but I can’t grade the thermal camera because I don’t have the FLIR to compare it to. But I can say this: the Seek thermal camera rocks and I will play with this some more and see what I can find.
Thanks to Pawel Wozniak and Morten Fjeld at Chalmers, for helping me with administrative issues while acquiring the camera. Thanks to Marta González Carcedo for letting me take a photo of you.
Movies mentioned in this post: