Calel,
FLIR operate the most efficient manufacturing process that they can achieve when producing thermal imaging cameras at it increases the profit margin. With the Ex and Original Exx series they used the same hardware and BoM for all the cameras so that only one hardware platform needed to be manufactured.. there were optional modules like Wi-Fi but they could easily be fitted after main production. The Ex5 series appeared on the market and presented some unusual resolutions that are not available in standard microbolometers. These immediately suggest that a larger microbolomter has had its output manipulated to provide a non standard resolution. There are two ways to reduce a microbolometers resultion, as presented to the user..... you can “Window” the microbolomter and select how much of the arrest is read out, or how much of the read out field is used. This is effectively a form of digital zoom and it effects the FOV of the produced scene. This is a crude resolution hobbling method that I have seen on L3 Thermal Eye based cameras. It is simple to apply, but also can be simple to reverse
The other option is manipulation of the image in the fully digital domain to down sample/scale a higher resolution array to behave like a lower resolution. This option permits the generation of non standard resolutions but care is needed with the down sampling/scaling to avoid significant image degradation for non simple scaling ratios. The advantage of this resolution reduction method is that it offers different resolutions whilst maintaining the same. FOV using a common lens specification across a range of cameras and thermal scene resolutions.
When looking at the specifications for the Ex5 series we see an unusual resolution is offered by one model yet the FOV remains the same for a lens of the same specification as the other cameras. This would suggest that the thermal resolution is a result of downsampling or scaling and not windowing. Knowing what we do about how FLIR operate, it is not unreasonable to believe that the Ex5 series use the FLIR 640 x 480 pixel microbolometer across the whole series and just reduce its resolution through down sampling/scaling to meet a specific cameras specification. I personally have not had confirmation that this is the case from FLIR so cannot confirm that belief as fact but the evidence Does support it.
So what are the other possible scenarios ? Well FLIR make the TAU2 core in different resolutions using the QVGA, QVGA+ and VGA microbolometers. Could they just be using one of the TAU2 microbolometers to suit a particular cameras resolution ? The answer is yes, it is possible that they could do this, but unconfirmed and not supported by the datasheet specification. The highest resolution E95 camera offers 464 x 348 which is a non standard resolution. That tells me that the E95 does indeed use a VGA microbolometer that is down-sampled to this unusual resolution. Can the full resolution be unlocked ? That very much depends upon how a FLIR have protected the down-sampling method and whether the camera is calibrated at its microbolometers native resolution or at the lower, down-sampled, resolution. I suspect full native VGA resolution Calibration would be simpler for FLIR though as down sampling/scaling can create anomalies !
Evidence from the data sheet of a VGA microbolometer and down sampling/scaling :
The Datasheet states that the microbolometer in all models uses 17um pixels.
The interchangeable lenses used across the series provide the same FOV in all models.
A QVGA 17um based Microbolometer would provide approx half the FOV of the VGA 17um Microbolometer when using the same lens. QED the VGA 17um microbolomter is present in both cases and down sampled/scaled in the lower resolution model.
The Ex5 model specs are available to compare here:
https://www.tester.co.uk/flir-e53-thermal-imaging-camera-24-degree-lens-240x180-20-deg-c-to-650-deg-c?gclid=CjwKCAjwrKr8BRB_EiwA7eFapi9fmQsz5luxU8HkocQoq9Fdzbe8NmKvYTHwe38yF00X8wbWvNB3OxoClIUQAvD_BwEI know this does not answer your question but it may enlighten you as to why a VGA microbolometer is strongly suspected. Mass production can sometimes justify ‘overkill’ or use of QA ‘rejected’ microbolometers for lower resolution applications. I am not saying that such is definitely the case here though. One thing I do know is that FLIR will likely not want to comment in case it leads to an effort to unlock the full resolution of the Ex5 series cameras to full VGA resolution.
So why has no one already tried to hack the Ex5 series cameras ?
The answer may be that they are very expensive and often in the hands of professionals who have no interest in hacking the camera. A hobbyist would need to have deep pockets plus a large risk appetite to start digging around in the firmware of an expensive Ex5 camera. The Ex series E4 was relatively inexpensive and so people were willing to risk bricking it in order to discover its secrets. FLIR have learnt from past mistakes and intend to make life harder for those wishing to unlock a cameras full potential. They used Win CE6 in the Ex and Exx series cameras. That is an operating system that is very vulnerable to hacking. I was told that the Ex5 is running Linux but have not had confirmation of that. If it is running Linux, it can be made far more secure than Win CE and that could make hacking of that camera far more challenging. As I say, this has not been proven by me or confirmed for me by anyone at FLIR. From a personal perspective, a move to Linux would be a very sensible idea for FLIR but it would mean a significant change for its firmware development team who are used to Win CE.
Time will reveal the secrets of the Ex5 series but for the moment we have only comments on this forum and their sources may be reliable, or not, as the case may be.
So Calel, are you considering jumping from an E4 to an Ex5 series camera now ? Considering your concerns regarding the Exx series, that is quite a leap and one which will offer you no upgrade options at this time. Or is this just a casual question out of curiosity ?
Be aware that some of us on the forum have had a long term relationship with FLIR and their products so understand some of FLIR’s ‘habits’. We also receive snippets of information through friends at FLIR. We are not able to make all information public as that would be a breach of a confidence in some cases.
Fraser