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Products => Thermal Imaging => Topic started by: Fraser on December 09, 2019, 08:21:18 pm

Title: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: Fraser on December 09, 2019, 08:21:18 pm
I bought this little beauty on eBay last week for 99 Pence ! No one bid against me so it was mine for the opening bid  :)

So what did I buy ?

The Agema Thermovision THV550 is a MWIR Stirling Cooled thermal camera that uses a 320 x 240 staring array rather than the single pixel scanning mirror design used in AGEMA models that preceded it. The THV550 was cutting edge thermal camera technology in the mid 1990's when I used one. The cameras case was based on the palmcorder format that was popular at the time. It was significantly smaller and lighter than the scanning type MWIR thermal imaging cameras like the THV880 and THV470. The image quality was excellent thanks to the 320 x 240 pixel staring array that was operated at 77K.

Is this model rare ? In a word yes. These cameras were very expensive when new and sales were heavily controlled due to the nature of the cameras internal technology and high performance. As a result not that many were in Industry and made their way onto the secondary market. They do occasionally appear on eBay but many eBay buyers do not know about this model. These are also a high risk purchase as a Stirling Mechanical Cooler is used to reduce the FPA temperature to -196C. As those who have read my guidance on buying such mechanically cooled cameras will know, if the cooler is faulty or has lost its Helium Gas fill, the camera becomes an interesting paperweight !

This THV550 was advertised as being in unknown condition so I fully expected it to have a dead cooler. I wanted it for my collection though. Of note was the lack of a charger or PSU in the pictured kit. This would mean that the seller was unlikely to be able to power the camera, hence it being sold as untested  ;)

I was thrilled to buy the THV550 for just 99p and the seller was a true Gentleman and honored the auction result  :-+

The camera kit arrived today and I quickly connected the camera to a FLIR PM series PSU to test it.........

The power button was pressed and the camera awoke from its sleep with the reassuring buzz of the rotary Stirling Cooler beginning its cooling cycle. Now for those unaware, the Stirling Cooler should take from approximately 5 minutes to 15 minutes to reduce the FPA to 77K (-196C). As a Stirling cooler suffers wear or loses some of its Helium gas fill, it takes longer to reach the target temperature. Eventually a cooler in need of a service is incapable of reducing the FPA to the 77K operating temperature and the camera is out of service. A cooler rebuild on one of these cameras in 1999 cost £5K  :scared: The price rose over the years until the cameras support eventually ceased all together. My new arrivals cooler sounded very healthy to my ears and I waited to see how long it would take for the cooler speed to reduce as it went into its 'maintain' mode. I was very pleased when this occurred at just 6 minutes as that is a very healthy cooling time  :-+ The cooler in the camera may be the original or it may well have been replaced at some point in the cameras life. The EVF display was showing a plain grey with no on screen graphics or thermal image. This is not that uncommon on the THV550 and FLIR PM series as the EVF can suffer failures in its electronics or the ribbon cable that connects it to the processor PCB. The EVF in the THV550 and later PM570 are the same and are taken from a JVC palmcorder of the era ! Such a fault was of no concern to me. I connected the external video feed to our TV to see if the camera was indeed operating except for the EVF....... it was  :-+

The camera will undergo a full service on my bench and the EVF will be repaired. I have plenty of spare JVC EVF units for just such patients. The RTC battery will also need to be replaced but that is to be expected ! 

I attach some quick pictures of my 99p purchase  :)

Fraser




 

Title: Re: A Stirling Cooled QVGA thermal camera for 99 Pence ! - Yep, no kidding.
Post by: Fraser on December 09, 2019, 08:25:49 pm
The THV550 pictures
Title: Re: A Stirling Cooled QVGA thermal camera for 99 Pence ! - Yep, no kidding.
Post by: Fraser on December 09, 2019, 08:32:46 pm
The auction......
Title: Re: A Stirling Cooled QVGA thermal camera for 99 Pence ! - Yep, no kidding.
Post by: Max Planck on December 09, 2019, 10:46:28 pm
Nice catch Fraser  :-+ but personally, if having a choice, I would prefer the cat.  ;D

Max
Title: Re: A Stirling Cooled QVGA thermal camera for 99 Pence ! - Yep, no kidding.
Post by: Fraser on December 09, 2019, 10:52:57 pm
 ;D
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99 Pence ! - Yep, no kidding.
Post by: Fraser on December 09, 2019, 11:55:59 pm
For anyone confused by the appearance of AGEMA, FSI and FLIR on the cameras splash screen......

AGEMA designed, built and then released the Thermovision 550 camera in 1995
FSI bought AGEMA and the rights to their product range, including the 550, in 1998
FSI rebranded as ”FLIR” (FSI was FLIR Systems Inc)

Simple really  ;D

FLIR kept the AGEMA branding on products for a while as the AGEMA brand was known and respected in both the industry and customer base. They then replaced AGEMA with FLIR branding once the purchase of AGEMA by FLIR was known and understood by the customer base. The AGEMA Thermovision became the FSI AGEMA THV550 up until its retirement. The AGEMA PM570 became the FLIR PM570 and all models that followed in the PM series were based upon the PM570 design.

History lesson over   ;D

Fraser
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: Vipitis on December 10, 2019, 01:15:55 am
where does this rank on your bargain scale? The SC6000 is a far more modern model but the price was a lot higher... Comapreable.

I am very surprised that it's working. Do you have any specifications? FPA, rated performance and lens?
The size is really unexpected, I have seen how large the scanner type cooled cameras were. There will hopefully be some side by side pictures with comparable camera models.

As this is meant as a standalone handheld camera(unlike the SC for example), what kind of digital data can it capture and how is the software situation with these things?

Meanwhile the auction I mentioned on the weekend ended at nearly 300€ for a SIM205 core with 18mm lens from and Evo 4000.
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: Fraser on December 10, 2019, 01:21:54 am
Was just cleaning my teeth for bed (01:00 here in the UK) and thinking about fitting a new RTC battery in the THV550 tomorrow...... I then remembered a little known issue with the RTC module in the PM series that likely applies to the earlier THV550 as well...... the camera is natively NTSC but can be commanded to be PAL where required. The TV standard is held in the RTC memory and read at boot. If the RTC fails it does not hold the PAL ID in the memory at boot and the camera stays in the default NTSC mode. So what ? Some may ask ...... well the NTSC cameras are fitted with NTSC viewfinders and the PAL cameras are fitted with PAL viewfinders. The viewfinder electronics are mono standard. If a PAL camera suffers RTC memory loss and boots up as the Default NTSC, the PAL viewfinder ‘throws its toys out of the pram’ and refuses to display the NTSC image. On later FLIR PM series models the later viewfinder electronics do display a weird raster pattern. This is not appearing on the earlier THV550 EVF. The camera I just bought is a PAL model and the RTC battery is dead so I bet that is why I am seeing a lit viewfinder that does not display any images.

This could well be the reason why the camera was withdrawn from service. FLIR would charge a small fortune to ‘repair’ one of these cameras.

More on this when I have sorted out fitting a new Lithium cell in the RTC module. Unlike the later RTC units used in PM575 and later models, this one does not use a Powercap so the cell must be desoldered and a new BR1220 fitted. Once this is done, the camera firmware writes the factory configuration settings (including the PAL ID) to the RTC memory chip on boot and these are then read out at the next boot, and normal service is restored. It will have been doing this every time the camera with a dead RTC battery booted, but sadly the data was lost every time the camera shut down.

It is little ‘features’ like this that I had to work out for myself whilst servicing these cameras. They are getting to an age when things like RTC batteries start to fail. Thank goodness no camera specific unique data is stored in the RTC RAM like in some test equipment ! It is also great that the firmware recognises the missing data in the RTC memory and replaces it with a fresh set at boot, ready for the next boot sequence  :-+

Fraser
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: Spirit532 on December 10, 2019, 07:01:05 am
My offer is £3 + p&p for the cryocooler to stuff into a... thing... for an SEM!
300% return on investment! ;D

Neat that the cryocooler is still in good shape.
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: Fraser on December 10, 2019, 12:01:57 pm
Spirit532,

I was pleasantly surprised to find the cooler in such good condition. As I said, the cooler may have been replaced at some point in time. These cameras were so expensive that they were often well cared for and maintained by their owners. This includes return to FLIR for firmware upgrades and servicing. I may have struck lucky and found a camera that has a cooler that does not leak :)

I will carefully clean the camera, service it and test its performance. I am so chuffed that it works  :)

Vipitis,

I will answer your post later.

Fraser
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: Fraser on December 10, 2019, 08:53:34 pm
@Vipitis,

I promised to respond to you and here it is :)

OK, when discussing the 1995 Agema Thermovision 550 Vs the 2005 FLIR SC4000 cameras we need to decide whether we are comparing similar hardware with the same intended purpose. The answer to that in this case is a definite no  ;) The THV550 is a portable high performance cooled QVGA MWIR camera. The SC4000 is a static high performance, high frame rate science QVGA MWIR/SWIR camera designed for demanding R&D tasks.

The Thermovision THV550 was cutting edge cooled technology when designed but a lot of cooled camera technology development occurred in the 10 years between it and the design of the SC4000/6000 cameras.

A brief bullet point comparison......

1. Resolution: both cameras are QVGA so equal.

2. Sensitivity : The THV550 is stated as <100mk. The SC4000 is stated as <18mk. In both cases performance was better than the specification when independently tested. The THV550 is a very low noise sensitive camera, but not in the class of the SC4000. 

3. Spectral Response : The THV550 is MWIR only. My SC4000 is wideband, covering MWIR and part of the SWIR band.

4. Frame rate: Both high. The THV550 is 60fps and the SC4000 is a specialist high framerate platform capable of up to 45khz in theory.The SC4000 far outperforms the THV550 on frame rate but then the SC4000 is a specialist high speed camera !

5. Portability : THV550 is very portable and runs on batteries or mains. The SC4000 is mainly used in a static role and powered from the mains. It may be vehicle borne and battery powered, where required, but it is not designed for handheld use !

6. Data output : THV550 has digital radiometric (TAXI-Parallel RS422), Composite video, S-Video and a removable PCMCIA memory card. SC4000 has Gigabit Ethernet, USB, Composite video and S-Video. Exact digital specs would need to be checked but are 14bit or greater.

7. Build quality: Both built to survive the rigors of industrial use. Metal casings combined with appropriate design makes them long lived and reliable within the limits of their mechanical cooler technology.

8. Optical blocks: The THV550 uses a fixed lens block to which supplemental lenses may be attached. The SC4000 uses a removable lens block that may be changed to meet the needs of the application. The dedicated lens block matched to the application normally out-performs the fixed lens block plus supplemental lens.

9. Cooler life : The THV550 uses a conventional rotary micro Stirling mechanical cooler of 1995 design. These coolers are precision devices that have an expected operational life of between 2000 hours and 10,000 hours, depending upon the exact model. The SC4000 contains a split Linear stroke Stirling mechanical cooler of 2005 design. These coolers are well known for their longevity and accelerated aging tests showed them to still be working at 100,000 hours ! The loss of Helium gas fill is less predictable and some coolers do lose their gas over time. The Rotary type coolers are considered to be at greater risk of seal failure than Linear types.

10. The THV550 camera is supported by FLIR Researcher and the SC4000 is supported by both FLIR Researcher and FLIR ResearchIR.

11. Cost comparison : THV550 was around $60K new in 1996. My specific SC4000 was around $150K new in 2008

I think that will do for now. In summary, the SC4000 is superior to the THV550 in all cases except mobility, but that is not a surprise to me. The two cameras were intended to be used in different applications. Both are very strong performers 'across the board' but the SC4000 is a 'Beast' of a thermal camera intended for serious science. It was designed for the U.S. Military to be used on their Missile Test Ranges ! The SC4000 user manual remains a controlled document as a result. The THV550 was designed to be a highly portable QVGA MWIR thermal camera capable of producing excellent low noise radiometric imagery without the need for Liquid Nitrogen cooling. It met that objective perfectly :)

Fraser
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: ArsenioDev on December 12, 2019, 03:07:14 pm
Fraser you lucky chap, guess this is what comes from watching the thermal market like a hawk. Mad jelly
Title: Re: A Stirling Cooled MWIR QVGA thermal camera for 99p (~$1) ! - Yep, no kidding.
Post by: Fraser on December 12, 2019, 04:58:01 pm
ArsenioDev,

The whole story of finding the camera will surprise you......

I was searching eBay for a thermocouple for my BGA rework station and for an unknown reason thought I would have a quick look for any old thermal camera parts. I searched on “Agema” and literally stumbled upon the Thermovision 550 auction and it had 33 minutes left to run and no bids ! I placed a sensible bid on a potentially ‘display only’ camera and fully expected someone to outbid me in the final seconds of the auction. The ‘challenge’ never came and the auction finished with just my bid present. I fully expected the seller to either write and say “sorry I cannot sell it for 99p” or to just refund me and say it was “lost”. I wrote to him asking if he was willing to honour the auction result and he turned out to be a really friendly and honourable chap. I have updated him on the fault on the camera and my ability to repair it and he is genuinely pleased for me. I am guessing this camera is not what he usually deals in and just a curio he put up for sale. He sells industrial kit.

Why I decided to search on “Agema” that day I do not know. Why no one else saw the camera and bid against me, I do not know. Then there is the 33 minutes remaining on the auction ! Fate or Karma certainly dealt me a good hand that day. I have wanted to own a 550 for a very long time and not only have I now got a decent condition example, but it still works ! Amazing  :-+

Another forum member managed to buy a THV550 a while back for around £100 and I was so envious of him ! His 550 was also in working condition. I did not expect to find such a camera for myself any time soon, if at all.

Since my New Years Resolution of 2018 I have stopped my multiple and comprehensive daily searches for thermal camera equipment and only buy unusual kit that peeks my interest. I rarely buy thermal cameras now and I have missed out on several nice and very affordable cameras and cores through no longer searching for them. One of the most painful for me was a lovely condition Bullard Eclipse Large Display model in a navy blue casing. It was sold from Germany and I should have bid on it  :(  On a positive note, my withdrawal from buying thermal cameras on eBay has meant that others get a look-in on auctions where previously I may have outbid them. It was still quite painful to miss out on some of the thermal kit though  :(

Fraser