The Electrophysics HotShot LT thermal imaging camera - an unusual design ! - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:15:17 pm
content: Another unusual camera recently camera into my possession. It caught my eye because of the unusual format and design topology. The unit described here is the Electrophysics HotShot LT “tablet thermal camera”The camera dates back to 2005 and was apparently designed for Electrophysics by a company with many years of experience in the thermal camera industry. I will give my thoughts on who that might be in a minute.The camera design is unusual in both looks and the electronics package. In terms of looks, I suspect it is a bit of a 'love it' or 'hate it' design ! I think of it as a bit of an ugly ducklingThe designer created a handheld fat tablet-like casing with large high-friction grip areas to ensure it is not easily dropped. Attached to that 'tablet', at one corner, is an eyeball-like thermal camera head assembly that can rotate in one axis only. At the centre of the tablet casing is a 3.5” colour LCD panel with resistive touch screen. In terms of physical buttons the camera has two button switches plus a navi-pad with central button switch. Many functions of the camera are accessed via the touch sensitive LCD panel.This camera differs from others of the period in a significant way. It contains a fully fledged PDA (Personal Digital Assistant) as the host to the thermal camera head. The PDA runs Windows CE and is able to act as a normal PDA so can create reports etc without the need for another computer. This writing of a report on the camera is a novel idea but would not be my first choice for such an activity. The manufacturers statement that the camera contains a PDA explains the portrait format touch screen display, soft buttons and the navi-pad. There is also a CF card expansion port in the top of the camera, very much like that found in HP PDA’s of the time. I wondered if it was a iPaq PDA hiding inside that bright yellow casing. No detail of the thermal imaging core manufacturer is provided but first impressions make me think it is VOx based and potentially a product of Electrophysics/SOFRADIR. I say this because Electrophysics/SAFRADIR advertised for 3rd parties to show interest in a new very compact thermal imaging core that they had produced and that was around the time that the HotShot appeared on the market with its compact eyeball like core housing.The camera core is equipped with motorized focus that is controlled via the navi-pad. Optional wide angle and tele-photo supplementary lenses were made available by Electrophysics. My unit came with the optional X0.5 wide angle lens that screws onto the accessory mounting thread of the eyeball camera head.Power for the camera is provided by a commercial off the shelf camcorder type Lithium Ion battery that provides 4 hours of camera operation. The battery may be charged either within the camera or in the provided external charger. Two batteries were provided and a new one was purchased for £17 so they are still available not very expensive.The camera can use its PDA internal memory to store images within the camera or a CF flash memory card may be inserted into the CF accessory port for saving on that removable media.In order to provide both thermal and visible light image capture options, the HotShot is provided with a CF card based visible light camera that plugs into the CF card port. This is an accessory originally designed for PDA’s and the HotShot qualifies as such so why notThe I/O port for connecting to a PC is a standard Mini USB port on the bottom of the camera, alongside the external 9V power socket. PC software is provided with the camera for image analysis and reporting.So what about the designer of this unusual camera ? Who could it be ? When I first saw the HotShot camera, I actually thought that it was from a different manufacturer. I had seen similarly bold case designs and flexible camera heads on products coming from Infrared Solutions. For those unaware, Infrared Solutions have been designing and making unusual thermal imaging cameras for many years, including the tablet format "FlexCam" that provides the user with a large display screen and a rotating thermal + Visible camera head alongside in a similar format to some Sharp Camcorders that I remember in the 1990’s. I will be honest and say that I have never really liked this camera case format. It is a personal choice kind of thing. I do not like the FLIR rotating camera head designs either ! That is just old fashioned me thoughBack to Infrared Solutions and their cameras…… the FlexCam camera has a similar casing design theme to the HotShot in that it is quite chunky and a bit like a Fisher-Price toy camera for children ! The FlexCam was grey in colour when first released, but then FLUKE bought Infrared Solutions sometime around 2007 and the camera casing was changed to the bright FLUKE yellow that we see today on the Fluke TiX series. The HotShot in its similar yellow colouring could easily fit into the Infrared Solutions/Fluke stable of cameras in my opinion. Until proven otherwise, I am working under the assumption that the HotShot is indeed a product of co-operation between Infrared Solutions and Electrophysics/SOFRADIR.If I am honest, the HotShot will not win any beauty contests ! I am drawn to it because of its unusual design and build around a PDA. This is actually quite clever and a similar idea to what we see these days with thermal camera heads being attached to mobile phones that then do the image processing and display ‘heavy lifting’. Back in 2005 the common handheld computer was a PDA rather than a mobile phone so it’s use makes perfect sense if you want a compact computer to build into a thermal camera system. Raytheon even used a PDA attached to the top of some of its cameras as additional processing capability for the BST based camera. I never really got on with PALM and IPaq PDA’s and they had an awful habit of losing my data and any programs if the battery went flat ! Later PDA designs used non volatile memory to protect the loaded programs and any data and I expect the HotShot to contain that better version of PDA. Electrophysics do provide a CD that contains both the PC image analysis software and the firmware package for the rebuilding of the PDA if the camera firmware becomes corrupted. Fortunately that invaluable CD came with my cameraSo how does the HotShot perform ? Well I must be honest and say that I have not used it much since it arrived but I am quite pleased with the low noise thermal image that it presents to the user. That said, it’s minimum span in automatic mode is 10C and the sensitivity is definitely inferior to modern cameras at 100mK. In automatic mode it does not clearly show the plaster dabs on my dry lined walls which modern cameras easily display.Is it rare ? It looks to be quite rare from what I can tell. It was a very different format of thermal imaging camera at the time of its release and I am unsure how the market responded to its rounded tablet format and rotating eye-ball camera head. The camera was intended to be more affordable than similar from other major manufacturers, but it was still a significant sum of money to invest in such a capability. Electrophysics continued with sales of the HotShot series of cameras for a while and produced a VGA version that had a rotating camera head that incorporated a larger lens and visible light camera, similar to the Infrared Solutions FlexCam series.Will I being delving inside this unusual camera ? Yes, but only when I have the spare time and sadly that is not at the moment. This is not a camera that I expect many to be that interested in but some may like to know what resides inside that bright yellow bulbous casing with an eye ball protruding out the sideFraser

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:17:48 pm
content: The optional X0.5 wide angle lens...

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:20:49 pm
content: The "Eye-ball" head .....

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:25:16 pm
content: The CF card visible light camera......

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:28:52 pm
content: The batteries, charger and CD supplied in the kit.....

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:36:26 pm
content: Images of the Hotshot operating. Sadly you get moire patterning on the LCD panel so the images seen do not do thos camera justice. It actually produces low noise, well defined images.The last pictures after the image of the camera fitted with the wide angle lens, show teh effect of teh lens and also teh result of using teh x0.5 lens and then applying X2.0 zoom

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:41:59 pm
content: Colour Pallets....

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:45:04 pm
content: Pictures showing the cameras Win CE operating system running on the internal PDA .......

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:47:58 pm
content: Lens parked (down facing and covered) and use positions with screen warning if still parked....

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:51:35 pm
content: More pictures of the casing without flash glare......

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 03:58:46 pm
content: Pictures of the HotShot series of cameras from the internet plus some of the Infrared System/Fluke Flex cam......

author: Fraser
author_rank: Super Contributor
timestamp: September 08, 2022, 04:02:05 pm
content: The Infrared Solutions FlexCam and later Fluke release in yellow livery......

author: Fraser
author_rank: Super Contributor
timestamp: September 09, 2022, 09:13:20 pm
content: The teardown has been completedWhat I found inside the HotShot camera was not what I expected. The PCB's a far larger than expected and in lace of a PDA motherboard I found what appears to be a Sharp LH7A400 equipped Single Board Computer.The Eye-Ball camera is a custom assembly with a well constructed aluminium lens barrel and rear mounted microbolometer PCB. On the rear of that PCB is another that is populated with an ATMEGA16. This appears to be a Mechacon PCB that controls the two motors and takes inputs from position sensors.The camera head uses two motors. One drives the iris that acts as a FFC flag and the other drives a lens for focus. Two opto sensors detect the position of the focus lens barrel.Without more ado, here are the pictures taken during the teardown .....

author: Fraser
author_rank: Super Contributor
timestamp: September 09, 2022, 09:18:21 pm
content: Continued.....

author: Fraser
author_rank: Super Contributor
timestamp: September 09, 2022, 09:23:38 pm
content: Continued.....

author: Fraser
author_rank: Super Contributor
timestamp: September 09, 2022, 09:29:58 pm
content: Continued.....

author: Fraser
author_rank: Super Contributor
timestamp: September 09, 2022, 09:32:25 pm
content: Continued......

author: Fraser
author_rank: Super Contributor
timestamp: September 09, 2022, 09:37:29 pm
content: Continued......