P2 PRO User experienceUpon first sight it was hard to believe that the P2 Pro could have anything more than very mediocre 'Toy' like performance. How could anything that small produce decent thermal images ? The author is pleased to advise that he was wrong in those first impressions of the device. It really is rather good
The Chinese thermal imaging microbolometer and core market has advanced in leaps and bounds over the past few years. The CoronaVirus Pandemic forced faster development of more affordable imaging cores that could still perform well. The P2 Pro is the perfect example of how the imaging cores have shrunk in size, yet are still able to produce accurate thermal measurements. The lens mounted on the camera will dictate how much detail in a scene may be resolved with 256 x 192 pixels but that specification is set by the manufacturer who is targeting a particular market segment. Personally I would prefer a 24 Degrees HFOV lens on such a camera, but the P2 Pro remains a very useable camera for general thermal imaging as well as close-up work. The P2 Pro is an enhancement of the already proven P2 camera. It has the benefit of greater temperature measurement capability combined with a supplementary close-up lens. The supplementary close-up (Macro) lens faciltates detailed thermal analysis of small objects, such as modern miniature electronic components on a PCB. The depth of field offered by the standard 56 degree HFOV lens is impressive. During testing it was determined that the P2 Pro was providing good focus from Infinity down to approximately 20cm. The close-up lens also exhibited a user friendly depth of field at its 25mm fixed focus distance.
The P2 Pro was put through its paces over a month of testing and familiarisation. The hardware worked well and did not exhibit any signs of instability or quality related issues. The design is both appealing to the eye and practical in many different deployments. Once mounted in the "Bostwickenator" designed tripod mount adapter the camera gained great versatility and the mounting options became almost limitless as detailed elsewhere in this review. It cannot be emphasised enough what an advantage it is for the thermal camera head to be so compact and rugged. This little camera punches well above its weight and offers much to the user and maker communities. The USB Type C male connector has proven to be very robust with no signs of flexing or fragility whilst in use. The "Bostwickenator" tripod adapter does assist in removing load from this connector by securing the camera by its rigid body and this can only be a good idea for the longevity of the USC Type-C connector if used in rough handling conditions.
The P2 Pro hardware is, of course, only part of the story. In order to produce a thermal imaging system using a dongle type thermal camera, it is necessary to provide a suitable host that provides the required processing power, communications and display resources. It is no surprise that Mobile Phones are the Host of choice. Modern models are equipped with powerful data processing capabilities and excellent quality display screens, all in a compact, self powered package, that can also provide power to the camera dongle. What is not to like ? Well the author of this review is a self confessed non-fan of dongle type thermal imaging cameras that literally hang off of the Mobile Phone host by their USB connector. To date he has tested the FLIR ONE G2, G3 and Seek Thermal Classic thermal camera dongles. They did not impress !
The issue with dongle type thermal cameras can be the challenges of producing a camera with adequate imaging performance, in a small form factor and the practical use of the system in normal life. The P2 Pro has impressed the author with both its size and imaging performance. It is so small that adding it to a mobile phone does not make the phone bulky or cumbersome.
The Host runs software that converts the data coming out of the thermal camera dongle into imagery that the User may view and save. A product can stand or fall based upon the quality of the provided software. The P2 Pro APP installed on four Samsung mobile phone models (S5, A6, A8 & S9), and one Motorola Moto G5 phone, without incident or difficulty. There does appear to be an issue with the camera not always being recognised by the software when plugged in, but this is easily resolved by deleting the APP from the phones history and re-attaching the camera. The APP will auto-start. Sadly the latest APP release has broken the Icon based start option as that reports "App not found". This is likely to be repaired very quickly though. In use the APP was stable and provided all of the features expected of such a piece of software running on a Mobile Phone platform. There are some oddities, such as the lack of menu rotation when the phone is used in the landscape mode and the saving of the 256 x 192 thermal images as 1440 x 1080 pixel up-scaled monster images. The saved images do appear inferior to the live images seen on the phones display. The camera and App also operate in an Auto Span and Level mode without the usual manual level and span options that can be useful. Thankfully the nature of Hardware/Software hybrid solutions means that such issues can be resolved in a new APP release.
Using the P2 Pro camera was both enjoyable and interesting. As a general use thermal camera, it performs well enough to provide good thermal insight into the environs surrounding the user. In a more directed use scenario, the excellent depth of field offered by the cameras lens enables well focussed imaging down to around 20cm without the need for a supplementary lens. For close-up inspection and analysis activities the P2 Pro supplementary close-up lens comes into its own. With a working distance of 25mm the close-up lens gives an excellent, well focussed, image of modern miniature SMT components on PCB's. The images produced were more than adequate for PCB thermal analysis. The combination of native close focus ability and a very nice supplemental close-up (Macro) lens means that the user may gain a good thermal overview of a large PCB and then add the Close-up lens to gain far greater detail of a specific area of interest. Attaching the P2 Pro camera to a simple, inexpensive microscope stand created a very capable PCB thermal analysis solution. Mounting the camera on an articulated arm created a very versatile bench thermography system for the observation of targets at greater distances than possible with the microscope stand.
Whilst a thermal camera solution may produce acceptable thermal images for general use, if it is to be used for temperature measurement, it needs to be a radiometric model with a design capable of providing accurate temperature measurements. The testing of the P2 Pro and associated APP proved the camera to be more than capable of accurate temperature measurements within its stated specification. Such a capability would be very useful for PCB thermal analysis and fault finding. The Emissivity and distance functions performed as expected and the camera passed the measurement accuracy tests.
Radiometric thermal cameras can offer several different ways to measure temperatures in a scene…
Centre spot measurement
Hottest spot measurement
Coldest spot measurement
Hottest and Coldest spot measurement within a region of interest
Hottest and Coldest spot measurement along a defined line cutting through a thermal scene
The Region of Interest (ROI) may often be a circle, square, rectangle, triangle or trapezoid, depending upon the options the manufacturer wishes to provide.
The P2 Pro keeps matters simple by offering two modes of measurement. Basic mode provides a centre temperature measurement plus the highest and lowest temperature in the scene. Perfect for a quick measurement. For more advanced measurement options the Pro mode may be enabled. This provides user selectable and positionable spot, line and ROI measurement options. The ROI is limited to just a user positioned variable size rectangle but this is adequate for most tasks. It is this ROI function that was used during the Measurement accuracy test as it provided useful information on the emission plate and any thermal gradient across it, if present. The Line and ROI measurement options provide the Highest, Lowest and Average temperature measurements. The relevant points along the line, or within the ROI, are clearly shown with coloured dot markers. With the option to deploy 3 of each advanced measurement type, the user has plenty of multi point measurement capability if wishing to monitor several locations within a thermal scene. The plotting of a measurement point on a graphical display or the saving of the measurement point data in a file is not currently provided in the App but we can but hope such an option may be added as it can be invaluable in R&D applications.
After a month of testing, the author has transitioned from sceptic to believer in this new miniaturised thermal imaging technology. The Infiray Tiny1 thermal imaging core that resides within the P2 Pro's metal casing is far superior to the equivalent cores from FLIR and SEEK Thermal. This review sample will be staying in the authors lab as a very useful and highly portable thermal imaging tool.
My thanks to Infiray for providing the sample P2 Pro camera for this review.
Fraser
Home
Help
Search
Login
Register
