Just to keep the balance here. Thermal imaging technology was, and is, designed to provide an accurate view of temperature level and distribution in a scene under investigation. It was not, and is not, designed to produce 'pretty' pictures. Such is very difficult in the thermal domain, unlike the visual domain. Artists are experimenting with the technology though, and the BBC have been using it to good effect for (relatively) high resolution imaging of wildlife.
The increase in resolution is very expensive but does produce 'cleaner' images. In the more affordable cameras running lower resolutions, it is helpful to see some context in the image so that the location of 'areas of interest' may be ascertained. One method of achieving this is using a higher resolution thermal imaging FPA, but these bring with them increased cost. 320x240 resolution FPA's do produce an image that the human brain can correlate with the visible domain in order to localise the area of interest. 80x60 resolution is a little more challenging, especially when working at some distance from the area of interest. The solution is often to move much closed to the target in order to gain a better understanding of the scene. Image fusion and image edge detail overlays are designed to provide the user with the context that would otherwise be missing. This in turn helps the user to recognise the area of interest. It should also be noted that scenes with low delta T across them are particularly hard to understand as the thermal contrast in the image is relatively flat. In such cases the target may be artificially stimulated to create thermal contrast, or 'markers' can be used to create points of reference. A marker may be created with nothing more complex than a heat gun or even a humans finger thermal transfer. If a visible overlay is available, it provides the points of reference needed by the user. In darkness near IR or visible light may be required.
Even the FLIR One Mk1 can be usefully applied to a situation where the temperature of a specific point in the field of view is desired. Do you really need to see every nuance of a circuit breakers shape in order to see that it is the only one running hotter than the others ? I think not. Can a 80x60 FPA detect a hot or cold spot on a wall ? Yes, if the thermal contrast is adequate. If someone does wildlife photography in the dark then the situation is very different. The higher the resolution the better ! Horses for courses
The SEEK claimed the advantage of higher resolution than the FLIR One, but it squandered that so claimed advantage with high image noise levels, less than ideal optics and a pretty poor software app that cannot set spans or even emissivity.
A final comment to end upon......
Thermal imaging has been the preserve of the rich for many years. Only recently has it been possible to buy used or new thermal camera technology without breaking the bank of most hobbyists. We are very fortunate to have this technology available to us. As a technology it uses the camera principles of EM wave collection through a lens and projection of such onto a surface that captures an image. It is very different to the modern digital cameras with which we are familiar however. It is relatively low resolution and the optics are very simple in most thermal cameras. When compared to the modern digital visible light camera, the thermal camera has more in common with a cheap web cam ! That is just the state of the technology as it stands today. It meets the needs of the market so there is little incentive for manufacturers to create new and highly expensive complex optical blocks. Much image processing is applied to the thermal data from the FPA in order to tidy it up for the user. It is still prone to some noise and softening of edges however.
Now military thermal imaging is a very different matter.....but we mere mortals are unlikely to get our hands on that sort of imaging equipment any time soon.
Aurora
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