Thermal Camera purchasing - The perils of buying a cooled camera - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 01:15:14 pm
content: The perils of buying cooled thermal camerasAs some readers will already know, I am a user and collector of thermal camera technology.At last count I own 39 thermal cameras of varying technologies and ages.My favourite cameras are those from the FLIR PM industrial series and some of the NEC AVIO models.I already own one cooled camera, the FLIR Scientific SC3000 that uses a Stirling cooled Quantum Well imaging array. When I say ‘cooled’, I do not mean temperature stabilised, that is very different. A cooled camera uses either Liquid Nitrogen or a closed circuit Stirling Cooler that produces temperatures approaching -200C. At one point in time there were cooled scanning cameras that used Peltier cooler stacks to cool a single pixel detector to -70C, but these are long obsolete technology.Cooled thermal cameras pre-date uncooled Microbolometers, but are still made and used for demanding situations where very low noise images are required without all manner of software manipulation algorithms that could corrupt the data. Such cooled cameras are very expensive to purchase and run. The Stirling Cooler alone costs around $15000 to the OEM and RICOR are a major player in that market.(http://www.ricor.com/innovation-technology/stirling-cooling-technology/)Why are they expensive to run ? Well they are a very high performance machine that contains pistons, seals and a gas fill of Helium that is at enormous pressure. Helium molecules can escape past seals and even through the thick metal shell of the cooler. This means that over time the Helium Fill pressure drops as Helium gas escapes from its captivity within the cooler. Mechanical wear in the precision components also leads to a drop in performance. It is not unusual for a Stirling Cooler from the late 1990’s to require a complete rebuild every 2000 operating hours. Stirling Coolers are usually rebuilt when they need a new fill of Helium. This used to cost me around £5000 when FLIR offered the service. It is most definitely not an amateur DIY proposition as ultra-pure(UP) Helium at pressures in excess of 200psi is used. So every 2000 hours or few years (depending upon the Helium leakage rate, you have to spend around $7500 on the camera.When looking to buy a thermal camera it is wise to investigate the technology that resides within, or else you may make a costly mistake. Many older thermal cameras are advertised on eBay as ‘unable to test’ or ‘sold as seen’. Be wary of such cameras and investigate why they are described as such. In many cases it is because they require liquid nitrogen to be poured into their internal Dewar (vacuum flask cooling chamber). Liquid Nitrogen is a very inconvenient consumable to need for your cameras use. Without it, the camera is a paperweight. If the camera is equipped with a Stirling Cooler , there is the distinct possibility that the cameras cooler is either faulty or has lost its Helium Gas fill, rendering it incapable of cooling the sensor array. Again, this results in the camera becoming a paperweight. You could have the cooler rebuilt, but I know of no cheap way to achieve this and such professional services still cost many thousands of Dollars, and the providers of such services are few and far between (usually return to OEM only), Many OEM’s no longer support such obsolete products.If a Stirling cooled thermal camera is found in working condition, be aware that it is a bit like an unstoppable egg timer, with its coolers life decreasing every day as the Helium escapes. Some coolers continue to work many years beyond their predicted life, whilst others fail more quickly. Even NASA have this trouble with their space rated Stirling coolers used for vehicle instrumentation cooling. Helium leakage can vary from one cooler to the next and some will remain working after 15 years, whilst others have lost enough Helium after 5 years to cause failure. Cameras that were used in labs may have received a rebuilt cooler several times during their life. If possible, establish when the last cooler was fitted. That is not the last calibration data so do not be confused into thinking that calibration involves a new cooler or re-gas.Some types of cooled camera have very hard lives. Namely those used in the military and CCTV applications. The coolers were often running for many hours and suffered mechanical failure before the Helium Fill was lost (bearing failure is a common issue in the Stirling cooler mechanics). With the introduction of new, and more reliable, uncooled TIC technology, many such cameras were consigned to the ‘Stores shelf’ or disposal basket. These cameras are unlikely to be operational and should be avoided.There is a saying in the UK…… “do as I say, and not as I do”I want to tell you a story.........are you sitting comfortably ?I recently saw a very nice condition Inframetrics PM280E cooler thermal camera for sale on ebay for a starting price of £600. I was interested in this camera as it is a mid-wave unit and this example was complete with the very expensive High Temperature filter. This may be attached to provide use up to 1500C. If I am truly honest, I have never liked the Inframetics PM series (very different to the FLIR PM Series). They did not seem as neatly designed in some ways. By the way PM prefixes usually just mean a series for ‘Preventative Maintenance’ . Both Inframetrics and FLIR had their own PM series camera and things got more confusing when FLIR absorbed Inframetrics into its ranks. But that’s another story.Anyway, back to the Camera in question…..I contacted the seller to establish some facts about the camera. It was apparently in excellent condition with all accessories and the important optional ‘HT’ filter. It was said to be in working order and the cooler was working OK. I asked if the Maintenance warning was flashing in the display and was told it was not. This is important as the warning indicates that the camera needs a service. If this has been ignored it does not bode well for the coolers maintenance. I satisfied myself that the camera was operational and advised the seller about the perils of buying a Stirling cooled camera.We agreed that if the camera did not sell on eBay, we would discuss a mutually acceptable price for it. The camera did not sell and I spoke with the seller again. He understood the risk of me buying the camera and asked for an offer. I offered £300 and he accepted. A great deal some might think (me included).The camera arrived and was in its posh flight case complete with all accessories and three batteries. I powered the camera via its mains adapter and the colour viewfinder burst into life. It immediately indicated “Maintenance suggested” at the bottom of the screen……. I got that awful sinking feeling that you get when you think you have been conned. I left the camera running to complete its cool-down cycle.A camera with a healthy cooler will take between 5 and 7 minutes for the cooler to get to operating temperature at the ‘cold finger’ (the attachment point to the sensor array). As the coolers Helium Fill diminishes, with associated lowering of gas pressure, the cooler takes longer to reach the operating temperature. A camera that takes 15 minutes, or more, to complete the cooling cycle needs a Stirling cooler service. My PM280E was still trying to reach operating temperature after 40 minutes…..there is insufficient Helium left in the cooler for it to do its job. It valiantly tried but failed to ever meet its target temperature. In STAR TREK speak….”Its dead Jim”OH cr*p was my response to this discovery. I had a lovely condition cooled thermal camera that promised so much but was incapable of cooling its sensor array. B*gg*r £300 wasted. It was a cash 'sold as seen' deal so there will be no refund coming my way any time soon.I advised the seller of the situation but, as expected, no response. His view is likely that it worked to the best of his knowledge (which was minimal on thermal cameras). My huge mistake was not getting him to email me pictures of the camera actually displaying a thermal image. I was not on the ball this time (others things on my mind), too trusting, and I have got myself burnt. You live and learn. I am telling this rather embarrassing tale in the hope that it prevents others making the same mistake.The bottom line is...... I recommend you do not buy uncooled thermal cameras unless you know an awful lot about a cooled cameras history and that it has a newish cooler fitted. Without such knowledge you risk buying a turkey, like I have just done.Remember..... if a cooled cameras Stirling cooler fails……. It’s is just a posh paper weight !I believe in KARMA and in my world I will not waste precious time chasing the seller or worrying about my loss. It could have been far worse as I have spent more than a £1000 on cameras in the past. This is my first mistake in 39 TIC purchases, so I have not done badly. I bought a beautiful condition FLIR PM575 for only £150 a few months ago so such bargains offset this loss.What of the PM280E ?Its fate is yet to be decided. I may sell it as spares, or break it up as a parts donor. It may just sit in my collection as a reminder of getting greedy and its potential consequences. That alone is probably worth £300 to me.An interesting side note for thermal camera fans….. the 16 Degree lens on the PM280E is not made with Germanium lenses. It uses two large ZnSe or ZnS lens elements, the front lens element having what look to be Fresnel rings on it. I knew some military lenses contained ZnSe or ZnS lens elements internally but this is the only camera that I have seen that uses them for the first two elements. ZnSe and ZnS both have excellent bandwidths and transmission figures. There is a conventional Germanium lens in the cameras bayonet mount, and this forms part of the lens system that may have other interchangeable lenses placed in front of it, much like the AGEMA 880 lens system. Part of it is in the lens barrels and part is fixed in the camera body. Modern thermal cameras with interchangeable lenses tend to change out the whole lens assembly right up to the microbolometer as they use smaller or cheaper lenses in their construction. Germanium is so expensive that OEM's tried to reduce its quantity in the optional lens barrels as much as was possible.Be careful out thereAurora

author: daqq
author_rank: Super Contributor
timestamp: June 30, 2015, 01:24:01 pm
content: Wow! Thanks for the text, I learned quite a lot.I don't suppose you'd be able to hack together a replacement for the cooler module, say, just replace the whole block with a liquid nitrogen holder?You'd get a working-ish, if impractical camera. Though you do not suffer apparently from a lack of them

author: Chanc3
author_rank: Frequent Contributor
timestamp: June 30, 2015, 01:31:24 pm
content: Could you not take him to small claims? Or is that too much effort?

author: BravoV
author_rank: Super Contributor
timestamp: June 30, 2015, 01:53:50 pm
content: Saved, bookmarked n subbed ... thank you.

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 01:57:51 pm
content: @Daqq,No desperation to get this camera workingThe construction of Dewar and Stirling cooled cameras does not lend itself to hacking the modules.With a Dewar camera, the most common detector is the single pixel type which views the output of a scanning optical block. The detector die is actually part of the Dewar and is also inside the vacuum. This avoids condensation issues.The Stirling cooled camera staring sensor array is an integral part of the cooler module. When you look at a TIC Stirling cooler you will see the large 'cylinder head' like assembly and at right angles to that you have the secondary piston housing that does the cooling of the sensor array. The sensor array is attached to the secondary piston permanently via the 'cold finger' and the whole lot is placed in a vacuum to prevent condensation and improve performance. The Stirling cooler can only cool a very small mass to approx -200C. Efficiency is greatly improved by an insulating vacuum. If you try to remove the sensor array from the 'cold finger, it will be destroyed.When a Stirling cooler cannot be rebuilt and has to be replaced, you have to purchase the whole assembly including a new sensor array. The TIC is then recalibrated to take account of the new sensor array characteristics. It looks like my PM280E had a new cooler fitted in 20002 as I have the calibration disk from that repair.I attach some pictures of Stirling coolers so that you can see what I am talking about.P.S. Liquid Nitrogen is very hard to obtain in the UK. I have an Agema 880 which I wanted for sentimental reasons (it was the first thermal camera I ever used). It was gifted to me but will never run again due to the lack of Liquid Nitrogen.Here is a video of a stirling cryo-cooler running with its cold finger exposed (no sensor array fitted as it is not from a TIC)Aurora

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 02:09:08 pm
content: @Chanc3,Its not worth pursuing. It was a Gentleman's agreement.Not being flippant about £300 but if I am honest, life is too short to waste chasing such a sum. It is not as though I did not receive something for my money. The lens and HT filters are worth more than £300 anyway so if I feel inclined I can recover my money by selling the set piecemeal.I just wanted others to realise how risky it is to buy these particular camera technologies, even if cheap.Aurora

author: bookaboo
author_rank: Frequent Contributor
timestamp: June 30, 2015, 03:47:40 pm
content: Thanks for the warning Fraser. To salvage the dead camera could you rip the insides from it and mount something like the 160x120 lepton or a hacked E4 module inside? Im thinking the high quality lens would add much to these sensors.

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 03:58:52 pm
content: @bookaboo,The Germanium lens will be AR coated for Mid-wave energy so that would need to be replaced for Long Wave microbolometer use. The ZnSe/ZnS lens is wide band and would work fine with an LW microbolometer core.Its more work than I would want to do though. I am somewhat spoilt in that I have many thermal cameras and also some thermal camera repairs that are more deserving of my time.Good idea thoughAurora

author: Alphatronique
author_rank: Regular Contributor
timestamp: June 30, 2015, 04:24:49 pm
content: Hisince it already a paperweight ,you may try to add extra gas to it and run it until bearing or seal failurethe good question is how many gas to add and how to add it

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 04:27:27 pm
content: I am sat here drinking a cup of tea and reading about re-gassing car A/C systems. They are talking about 210psi in those systems. I am not used to dealing with A/C's so the pressures sound a nightmare, but from what I have read they are normal and manageable even for the DIY enthusiast.Can you see where I am going with this yet ? I am both a mechanical and electronics engineer so provided I use my old grey matter, I may be able to come up with a way of re-pressurising the PM280E Stirling Cooler with Helium. I am aware that I need UP Helium rather than dirty old Balloon Helium so that will need some tracking down and renting of a bottle. Hoses and gauges for car A/C re-gas should be OK by the looks of it (ebay here I come) but there will be one major challenge that I must overcome. Connecting the gas line to the female threaded receptacle of the Sterling Cooler. From memory, the filler port is 'just' a threaded hole with a conical seat at the bottom. Once filled with Helium, a special threaded seal screw is driven down until it seals against the seat. It is a metal to metal seal to avoid Helium leakage. Hmmmm sounds challenging !I have nothing to lose and everything to gain if this can be achieved and the cooler recharged with Helium. I can then re-fill my FLIR SC3000 cooler when the time comes for such. This definitely sounds like a project for the future though. I will see how much it is likely to cost and decide whether to proceed based on economics.Aurora

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 04:31:56 pm
content: @Alphatronique,Great minds think alikeThis is also an opportunity for me to learn about re-gassing refrigeration systems :-)What I am unsure about at the moment is whether it is essential to vacuum the system down before adding the Helium. Maybe on such a small unit I can get away without doing so ?Aurora

author: mikerj
author_rank: Super Contributor
timestamp: June 30, 2015, 04:47:15 pm
content: Quote from: Aurora on June 30, 2015, 02:09:08 pmA shame that only one gentleman was involved in this transaction, but that's eBay for you

author: Alphatronique
author_rank: Regular Contributor
timestamp: June 30, 2015, 05:51:55 pm
content: that may price less to see the head of the local machine shop when ask for surface finish for gas tight metal to meal for helium

author: Kevman
author_rank: Regular Contributor
timestamp: June 30, 2015, 06:57:06 pm
content: I don't know why 210 psi would sound like a nightmare- its really no big deal (the off pressure on my grandfather's home air compressor is 200). Its certainly not uncommon. All but the crappiest of rubber hose can handle it, and I don't know that I'd call it dangerous in any capacity.Remember that welding and other gas tanks are usually like 2000+, vehicle fuel and oil pressure can get higher. And waterjets can hit 90,000.You may be able to rent a vacuum pump from your auto parts store. Its pretty much required any time you empty a car's AC unit use a vacuum pump. It won't get you high vacuum but it'll certainly get most of the air out.

author: Alphatronique
author_rank: Regular Contributor
timestamp: June 30, 2015, 07:04:28 pm
content: problem it that it not air but helium ,that so tiny that pass/diffuse trough rubberso everything start to be quickly complex when deal whit helium and specially when need to seal it for long time

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 07:09:23 pm
content: @Kevman,I have to agree with you, 210psi is not that bad when you look into it. It just sounded a lot compared to my car tyresThe actual pressure of the fill is 260psi. I checked and BOC supply small Helium cylinders that are pressurised to 200 BAR (2900psi !) Plenty high enough for the taskThis is a journey of discovery for meAurora

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 07:12:32 pm
content: @Alphatronique,Exactly. This is why these cryo-coolers are a bit of a maintenance liability. Helium is a bit of an escapologist and refuses to remain contained for long, even in a solid metal container.Aurora

author: Fraser
author_rank: Super Contributor
timestamp: June 30, 2015, 07:19:10 pm
content: I thought I would give you guys a giggle......A cooled camera to be avoided ?Some time ago I saw a PM380 for sale on ebay. It was a spares or repair unit the like of which I have not seen before. The seller is known to me and asks silly prices for his items so the price was no surprise to me. I actually offered him $100 as I wanted the Stirling Cooler to dismantle. He counter-offered $280 ! What a joke. Needless to say I passed on it. I see that the unit has now sold.http://www.ebay.com/itm/Broken-Parts-FLIR-Inframetrics-ThermaCAM-PM-380-Thermal-Imager-Camera-Corpse-/231373351775?pt=LH_DefaultDomain_0&hash=item35deed2b5f&nma=true&si=JD7hxzq%252Bx5kCpkIYZ1deuNE1gM8%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557If he can sell that pile of cr*p for more than $100 there is still hope for my PM280It looks liek it has been exhumed from an underground resting place !Take a look at the pictures.....suggestions on how it got into such a state invitedOne careful owner ?Aurora

author: artag
author_rank: Super Contributor
timestamp: June 30, 2015, 07:26:31 pm
content: Quote from: Aurora on June 30, 2015, 01:57:51 pmIt's not so difficult. The main problems are the delivery, and what you keep it in. You really need a dewar of your own. We've had regular deliveries (every 6 weeks) at our hackspace fromhttp://mansfieldcryogenics.com/for £500 per year. As I understand it, most of the cost is in the delivery - it doesn't make much difference how big your dewar is.

author: ir.ukrm
author_rank: Contributor
timestamp: July 26, 2019, 04:40:55 pm
content: I see a flame filter in the set, I wanted to know if you worked with it?

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2019, 05:00:02 pm
content: No sadly I have not done anything with the flame filter. The two PM280’s are inoperable but I could test the filter with my Amber Radiance 1 or FLIR SC4000 as they are both SWIR. The problem is that it is quite a small diameter filter due to its intended deployment between the lens and the sensor array. As you likely know the filter enables viewing of the inside of boilers and furnaces that have flames present. Not a great deal of use in everyday scenarios.Fraser

author: cnxunuo
author_rank: Regular Contributor
timestamp: July 30, 2019, 10:55:47 am
content: My photon HRC needs around 30 sec to cool, it seems the cold finger has smaller than usual thermal mass than older or newer models.I once own 3 of them from a electronic waste dealer, however one had died before my hands due to helium leak.

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2019, 11:35:06 am
content: Cnxunuo,It is so sad when an otherwise good condition thermal camera or core is rendered useless by a leak or low pressure in the Stirling cooler. I see that your coolers are the rotary type. If they suffer any form of mechanical failure it is normally pretty obvious from a change in the sound they make when running. They are never exactly quiet but the one I have with a failed bearing makes so much awful noise That I have to wrap the camera in a towel to attenuate itHelium fill loss can be checked by placing the cooler/camera in an environmental chamber (or DIY equivalent). If the camera can not achieve or hold the cold finger at less than 77K in an ambient temperature of 35C, it is in need of a recharge very soon. If it cannot achieve 77K at 20C it is toast and needs a recharge. If a camera with reduced Helium fill is placed in an environment that is 5C, it will sometimes achieve 77K in order to test other functionality. Reducing the environmental temperature to -5, -10 and -20C (in a freezer) will also sometimes get a sick cooler to 77K for testing. I did this with one of my PM280 cameras in order to check its other systems and FPA condition. The camera complained at -20C though as other systems did not like such a low temperature.My SC4000 achieves 76K in less than 5 minutes so is nice and healthy. I note in the GUI configuration software that I can set the cold finger temperature at which the camera enables image collection. On my SC4000 it is set at 80K. Sadly if your Photon HR is only getting down to 80K and not 77K, or better, it is definitely due for a service. As I have already commented elsewhere, FLIR demand enormous sums of money to service these cooled cores and cameras.I have yet to find anyone who has succeeded in refilling a thermal camera grade Stirling cooler with Helium and returned it to normal operation. Even those who have purchased the correct UHP Helium and rented the correct filling equipment have failed to restore normal performance to a RICOR cooler. I would love to hear of success stories but these coolers are not very common in the hobbyist arena and many hobbyists sensibly buy uncooled cameras to avoid cooler induced failure and so loss if investment.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2019, 11:52:16 am
content: Cnxunuo,What software are you using to configure your Photon HRC core ?The full GUI configuration utility that FLIR sent to me has all manner of useful factory configuration options hidden behind a password. I was very pleased to obtain that utility and already knew the service menu password to gain access to the deep configuration settings such as the cooler temperature threshold for imaging and the cooler information page that showed the hours run on the cooler.The GUI configuration utility supports many cameras and cores, maybe even your Photon HRC.Fraser

author: cnxunuo
author_rank: Regular Contributor
timestamp: July 30, 2019, 12:11:32 pm
content: Hi Fraserthe 80K seems to be a set point, as it very quickly get down to 80 and reduced its RPM to save energy, I ran my RICOR without feed back at full power, it can happily get down to 60k, I think its helium condition and bearing (I believe it's a air cushioned bearing) are fine, operating hours around 50, taken from a Russian mower gimble by myself. it is very very unexplained why a Russian gimble which uses russian fiber gyro and swiss motor, Chinese video ethernet encoder, but uses a flir core....I used the online provided HRC software which is not compatible with any other core, it can perform service such as LUT calibration (there's 3 set of pre calibrated table to choose from and they give different noise patterns when booted, I think flir went thru the trouble of calibrating it 3 different times before shipping them out)thanks for the information about other software, however as I am chinese and NOT allowed to obtain any itar related softwares, I don't want to get myself and you into trouble by trying the fascinating software you mentioned.At a aviation show in China, I tried their knockoff version of ricor cooler with knockoff 15um pitch InSb FPA, cant tell a different between my flir one, it seems to be a direct copy,

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2019, 05:04:30 pm
content: You are absolutely correct. I would not breach ITAR, BIS or Wassenaar dual use regulations.The following document may be of interest to you though....https://www.export.gov/article?id=China-U-S-Export-ControlsThe issues around controlled dual use technology exports to China revolve mainly around military use and orders destined for military projects. Where civilian use is concerned, especially by individuals, the USA appears more relaxed. This is why it is not uncommon to find controlled US technology being used in China for non military applications. Some common sense is thankfully applied to requests from scientific institutions etc. Very capable microbolometers from ULIS are exported to China in order for then to be used in Chinese built thermal cameras. There are likely ‘in country’ checks on their use but it is mainly a paperwork exercise. Wuhan Guide were/are using ULIS microbolometers from France.As you already have the required software to drive the imaging core you do not need FLIR’s help anyway. Your unit with only 50 hours run time sounds greatFraser

author: cnxunuo
author_rank: Regular Contributor
timestamp: July 30, 2019, 07:40:37 pm
content: Hi FraserI am aware that flir-china seems very, very, sometimes too relax about academic use of high frame rate thermal cameras in china for some reason (perhaps because sells people are Chinese and they fabricate export documents to save buyers time in order to get more sells), around 3 years ago I was a undergrad in china, we bought a camera which could be used in binning mode to achieve 1500fps, we used it to study micro fluid inside hydrogen fuel cell. we got the unit directly from flir china, without filling any export related documents, not even a end user agreement was needed, Flir representative in china just “take care of everything for us” when I asked since I was an thermal camera enthusiast since a schoolboy and . from digging for price information publicly before purchasing, I found out that at least one of the unit was purchased solely for ammunition study in one of the institute, I presume they didn't go thru any export with flir china....maybe this is why they got fined...as for ULIS, since their mems structure isn't that shock proof, I dropped my thermapp 384 once or twice, and loads of new dead pixel appears, so gun sight and missle cant use them. VOx are much more resilient to shock from my own experience dropping photon and tau, cant observed any new dead pixel when dropped.There is a VOx knockoff when I went to the Zhuhai air show in 2016, they were showing some of the sights which has noise patterns similar to Flir from my limited time (1-2sec) to see thru them, I was carrying a thermapp on my phone so everybody demonstrating their thermal camera became nervous when I pick up their display item and tried to kick me offsite...Anyway I fully respect itar being a hobbyist, and 9hz is enough for me for most of the time. It seems, strangely, there's less thermal camera in UK ebay than in Chinese online markets. people in UK seems happy with their analog CCTV camera while many CCTV in china, 5% I guess, are thermal (from hikvision, don't know what core they use).

author: Hydron
author_rank: Super Contributor
timestamp: August 02, 2019, 04:49:02 pm
content: I know for a fact that ULIS sensors are used for weapon sights (in addition to other military applications). I do not know anything about the packaging of the system or what they are mounted to though - maybe it is sufficiently protected that it handles shocks better than a consumer grade unit (remember that dropping stuff into hard surfaces can produce some pretty high forces!)

author: tske
author_rank: Regular Contributor
timestamp: April 20, 2025, 02:49:35 pm
content: It's 10 years since the OP posted, yet still no affordable cooled/MWIR cameras, not even second-hand ones

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: April 20, 2025, 03:26:32 pm
content: Quote from: tske on April 20, 2025, 02:49:35 pmI dunno, me and my crew have obtained a SXGA 12um pitch unit for 1500, two L3 NC2s (VGA) for $600 each and each FLIR 8500/7500 (QVGA) for $2000 each. Oh and a crashed Safire-380 (SXGA)The difficulty is they are COMPLEX and difficult systems to deal with, and a bear and a half to get information about due to controls.we do NOT recommend for people unfamiliar with the architecture and deep debug and RE.Not worth for most people, we've spent WEEKS on debug and trying to nail down pain points, there's so many pain in the ass parts with the various vintages.China has some COTS SLS cores with zoom lenses for about 35K.

author: tske
author_rank: Regular Contributor
timestamp: April 21, 2025, 12:36:09 pm
content: Yes that's another problem, most cooled cameras are not hobbyist-friendly, they require complex external hardware and software to run.

author: nikitasius
author_rank: Regular Contributor
timestamp: April 21, 2025, 04:34:21 pm
content: Could be great to get the cooled "freezer" like cooled camera 🤓-21 -- 34°C is good enough for a hobby purposes guess.W/ gas you can cool DIY to -27°C. I tried it on a non-cooling chinese type-C camera i had and sold it. Idk why they don't do that.

author: KE5FX
author_rank: Super Contributor
timestamp: April 21, 2025, 09:31:55 pm
content: It seems possible to distill LN2 yourself withreasonably low effort and expense, although you'd probably prefer to scale it down further than this guy did.Medical oxygen concentrators may be a good source of some of the hardware, and they are far cheaper and more widely available in the post-COVID era than they were in 2015 when you (Fraser) started the thread.

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: April 22, 2025, 02:34:27 am
content: It doesn't change the response of a microbolometer.MWIR use direct photon conversion via photodiodes, not a bolometer pixel.the III-V semicons in those bands don't have a great bandgap until they're cooled down, so won't even really work.The other difficulty is removing the cryocooler without breaching the IDCA vacuum, don't really recommend trying to LN2 mod a MWIR.

author: tske
author_rank: Regular Contributor
timestamp: May 21, 2025, 01:18:38 pm
content: Just bought this:https://www.ebay.com/itm/388446750994?A GF306 for $200, new seller just registered. Maybe I'll get an empty box?

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: May 21, 2025, 01:51:53 pm
content: Quote from: tske on May 21, 2025, 01:18:38 pmOh damn you, that one pinged my scans this morning and I wasn't able to snag it. GG

author: Fraser
author_rank: Super Contributor
timestamp: May 21, 2025, 02:08:44 pm
content: If the camera does arrive, you can have some fun with it, but you may decide to sell it for a profit to buy other, more useful, cameras.Sadly Gas Imaging cameras like these have non removable hardware filtering built into them in order to display the desired gases. As such, they may not show you much outside of their intended pass bands. Very expensive specialist kit, but sadly sometimes too specialist to be a useful general purpose cameraThe GF306 has a spectral range of 10.3um to 10.7um from its Quantum Well FPA, so it is a cooled long wave camera with tight spectral filtering for gases. It might provide some general thermal imaging capabilities as the QWIP FPA was used in general purpose cooled cameras such as the SC3000, but do not think it faulty if it does not.Great find, I hope you get a good profit on it if you decide to sell it on.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: May 21, 2025, 02:31:02 pm
content: The good news is that the GF306 does appear to image targets other than just gases and gas leaksThe brochure clearly shows example images where structure is clearly visible around gas events.

author: tske
author_rank: Regular Contributor
timestamp: May 21, 2025, 03:08:50 pm
content: Quote from: Fraser on May 21, 2025, 02:08:44 pmI remember most/all QWIP cameras have very narrow band of response, such as your SC3000 (8-9um).Are they really all filtered? Or just tuned the sensor itself?If a 0.4um band can archive 15mk NETD, then the unfiltered LWIR sensor will have a insane rating...

author: ArsenioDev
author_rank: Frequent Contributor
timestamp: May 21, 2025, 03:26:37 pm
content: Quote from: tske on May 21, 2025, 03:08:50 pmUsually the filter is partially the sensor response of the QWIP bandgap and partially the front window of the IDCA.

author: Fraser
author_rank: Super Contributor
timestamp: May 21, 2025, 05:55:01 pm
content: The weird thing about thermal camera based gas detection is that you are effectively looking for the absence of energy. The camera sees a background that is producing thermal energy and it is against this background that the camera detects the absence of that energy at the gas absorption wavelength. Or at least that is how I understand the physics of the gas detection process. So thinking about that process, the camera has to be able to see thermal emissions from the areas surrounding a region of interest to see the energy absorbing cloud of gas at the desired wavelength. The issue is that the spectral filtering can be quite tight so as to improve detection of the desired gases. I will be interested to hear how you get in with such an unusual thermal camera.Fraser

author: tske
author_rank: Regular Contributor
timestamp: May 22, 2025, 11:57:06 am
content: Thank you Fraser and ArsenioDev.I wonder anyone knows the release year and MSRP?

author: tske
author_rank: Regular Contributor
timestamp: May 22, 2025, 12:05:37 pm
content: I've read the whole manual of GF306 and have a few thoughts.This camera have 2 lens choice, the widest one is only 24 degree HFOV. Personally I consider 45 degree as the minimal usable HFOV. But there seems no user calibration option, meaning I will get vignetting using those LWIR lens from my junk box. Maybe I have to get some 3rd-party supplemental lens.Among the whole series, only GF306 have 10 minutes cooling time, all other models are 7 minutes, why?By the way, the manual said "thousands hours" of cooler lifetime, but how accurate is that?There seems no settings for integration time, I would love a 20hz video with 3x sensitivity.It does have continuous AGC, which is good, many old ones I saw don't have it.

author: Fraser
author_rank: Super Contributor
timestamp: May 22, 2025, 03:40:40 pm
content: The operational life of coolers varies with the type and age of design. Many early miniature Rotary type Stirling coolers had a service life of approximately 2000 hours. This life has increased over the years as new designs and materials were used in their construction. I have seen some modern Stirling coolers with an MTBF of 10K hours. Sadly, a little like light bulbs, the operational life of a Stirling cooler can vary greatly. Some used to die before 2000 hours (usually Helium leak relate), Some made it past 2000 hours but failed soon after (mechanical wear) and some have lasted far longer than the OEM predicted. The operational life is not a precise science, even for Space rated Stirling coolers used by NASA. NASA carried out extensive testing on Stirling coolers as research for their mission use. Improvements in design meant the units tested lasted well, with only a few early failures due to defects. The longest service life came from Linear Stirling Coolers and 100K+ hours is not unknown.Stirling coolers have a heat pump rating for their cold fingers ability to cool a sensor array. The coolers used in portable thermal cameras do not have that much cooling capacity at the cold finger so operate it in a vacuum to improve efficiency. The thermal mass mounted on the cold finger will have an effect on how long it takes for that thermal mass to reach -196 Celsius. Not all Stirling coolers and FPA’s will be the same, so some cameras may take longer to reach -196 Celsius than others and this is not normally an issue.Integration time on cooled photon collection well cameras is quite a complex topic as changing the cameras integration time needs to be done with an understanding of the effect on the imaging system. There are preferred integration times associated with the expected target temperature range within a scene. This is important so as not to reach photon well saturation. FLIR wrote a useful paper on integration time and I attach it here.Note that on my SC4000 science camera, whilst I can change the Integration times and biases, I have to carry out an NUC calibration before I can use the new settings. Science cameras often provide far deeper access into a thermal cameras settings than would normally be available on a “General Purpose” camera. Whilst that may sound good, it can mean that such highly configurable Science cameras need a lot more configuration and babysitting than a GP type camera that is configured to provide decent images in most situations. Thankfully my SC4000 has multiple memories for different configurations (inc associated NUC) so I can set up custom integration times etc, calibrate the camera and save the configuration for future use.Fraser

author: tske
author_rank: Regular Contributor
timestamp: May 23, 2025, 01:26:39 pm
content: Thank you, from the PDF it seems the required integration time is always much lower than frame interval.

author: tske
author_rank: Regular Contributor
timestamp: May 23, 2025, 01:33:25 pm
content: By the way, I just found that my current uncooled cameras really struggle to produce usable pictures in a room without artificial heating or cooling. This include good modern cameras such as E8, TAU and Boson.I'm actually so surprised by this because I began to play with thermal cameras from night vision, and I always thought thermal cameras are my end goal because they will produce image in any condition. Well, how sad that's not true.I'm looking forward to test the new cooled one, if it will ever arrive.

author: Fraser
author_rank: Super Contributor
timestamp: May 23, 2025, 02:20:55 pm
content: Night vision enhancers and thermal imaging systems are very different beasts.With night vision you are either relying upon the available ambient light or providing the required illumination of the target with your own illuminator, normally Infrared. In the absolute absence of ambient light or an illuminator, a night vision enhancement system cannot show you anything. There are no photons available to enhance. This applies to simple IR sensitive camera types of night vision and image intensifier technologies…. No photons = no illumination of the target = no image of target.With thermal imaging there is a need for thermal energy to be emitted from a target or reflected by a target being illuminated by a local source of thermal energy. Thermal imaging systems display the different levels of thermal energy present in a scene. Everything above Absolute Zero generates thermal energy but most uncooled thermal cameras can only display that energy down to -20 Celsius or -30 Celsius. In order for a thermal scene to be anything but a flat field of constant thermal energy, there needs to be differences in the level of thermal energy emitted from, or reflected off of, th3 targets in the scene. The difference in energy levels can be very small and because of differing nervy output from the surface, differing Emissivity of the surface or localised illumination by another thermal energy source local to the scene (even your own body heat is a heat illumination source. The basically means that you need both thermal energy and thermal contrast in a scene in order to see details within it. No thermal energy = a cold flat image containing no scene detail. No thermal contrast = a scene at a temperature level that may be measured, but no detail of specific targets in the scene is visible.A thermal camera has a specification for NETD that gives a hint at its thermal sensitivity. That is to say, the minimum temperature differential in a scene that the camera is capable of showing to the user. That said, an NETD of 45mK does not mean that a user will be able to see a temperature difference of 45mK in a scene. The better specification for what a user can see in a scene with low thermal contrast is MRTD (Minimum Resolvable Temperature Differance) which is the difference in the temperature of two surfaces that the thermal camera can actually show to the user and that they will be able to see. That MRTD figure for a 45mK NETD spec camera can be something like 100mK. The better the thermal sensitivity of a thermal camera, the better it will be at imaging low thermal contrast scenes. If a thermal camera generates a lot of internal noise, creating a poor NETD figure, the noise can effectively mask small temperature differences between surfaces. With all that said, digital image processing can pull detail out of a low thermal contrast scene that would not normally be visible to the user. Signals in the noise DSP etc.Both night vision systems and thermal imaging systems convert energy into something the user can see. In the complete absence of that energy, they can show you nothing. Then there is the need for contrast in both cases. Contrast provides detail of object boundaries and finer detail. Without contrast you have a flat scene with little to no detail visible.The Wiki on MRTD……https://en.m.wikipedia.org/wiki/Minimum_resolvable_temperature_differenceFraser

author: Fraser
author_rank: Super Contributor
timestamp: May 23, 2025, 02:32:04 pm
content: Following on from my previous post relating to the energy needed to image a scene, there is the option to generate energy in a scene to provide the required illumination for reflection and emission. In the case of IR night vision, an Infra Red torch is used to illuminate the region of interest and the IR light is reflected back to the image enhancement system. With thermal imaging there is not really an analogue to the IR torch, apart from maybe a flame thrower !Instead a scene has thermal energy introduced into part, or all of it. In a building the heating systems may be turned on to warm up the area on interest and differing Emissivity values will start to provide scene detail and temperature differentials caused by things like thermal bridges to cooler areas will become visible. The user is effectively introducing thermal change into the scene. For localised areas of interest a more confined form of thermal illumination may be employed in the form of powerful halogen lamps or hot air blowers (heat gun) and the area of interest is warmed and then monitored as it cools. This technique can reveal flaws hidden in a wall or laminated material for instance.Active Thermography…..https://en.m.wikipedia.org/wiki/Active_thermographyFraser

author: Fraser
author_rank: Super Contributor
timestamp: May 23, 2025, 02:55:07 pm
content: Regarding the GF603 imagery in low thermal contrast scenes….. please do remember that the GF603 is a camera that has been tuned to detect gases at specific wavelengths, so it’s usability and performance in general thermography scenarios could disappoint. Yes the camera is cooled and very sensitive, but it will have a relatively slow lens on it compared to a LWIR microbolometer camera and the effects of the narrow band gas filter could degrade imaging sensitivity as you move away from the filters passband. The GF603 does have a high sensitivity mode for the detection of gas plumes, but this is like some really harsh contrast enhancement process and may not be to your liking in general use applications.Fraser

author: tske
author_rank: Regular Contributor
timestamp: May 31, 2025, 05:52:52 pm
content: Quote from: tske on May 21, 2025, 01:18:38 pmThe seller never send it nor reply message, fully refunded automatically.@ArsenioDev No need to envy me anymore.

author: Fraser
author_rank: Super Contributor
timestamp: May 31, 2025, 08:16:44 pm
content: Sorry to hear this news. I have had similar experiences recently, but not with thermal cameras. People advertise items on a “Buy it now”, I buy them and then never get a response to messages when they are not shipped. I am wondering what the scam is as eBay do not pay the seller until delivery is confirmed. Such sales are a waste of time. The more obvious scams ask you to pay direct after purchase by bank transfer and not via the safety of eBay or PayPal.Fraser

author: samuel_hayden
author_rank: Contributor
timestamp: August 05, 2025, 06:48:47 pm
content: Quote from: Fraser on July 30, 2019, 11:52:16 amFraser, do you have the utility you mentioned that might work for the Photon HRC? I have a working core that I would like to poke at more in-depth but I've been struggling to find the FLIR ICDs for the camera itself.

author: Fraser
author_rank: Super Contributor
timestamp: August 05, 2025, 08:06:57 pm
content: Sadly my SC4000/6000 GUI will not work with the Photon HRC.

author: samuel_hayden
author_rank: Contributor
timestamp: August 06, 2025, 05:08:15 am
content: Quote from: Fraser on August 05, 2025, 08:06:57 pmAh, worth a shot. Thanks!

author: MrSheep
author_rank: Frequent Contributor
timestamp: August 13, 2025, 01:25:33 am
content: @samuel_haydenDo you have pictures of the Photon HRC? I believe I have the same core in another camera of mine. Depends on what the proximity electronics look like, but they could be using the same detector.

author: samuel_hayden
author_rank: Contributor
timestamp: August 13, 2025, 06:17:56 pm
content: Some pics.

author: MrSheep
author_rank: Frequent Contributor
timestamp: August 13, 2025, 06:25:15 pm
content: Yeah this seems like a common IDCCA. My Proximity Electronics are identical. Thanks

author: samuel_hayden
author_rank: Contributor
timestamp: August 13, 2025, 06:38:05 pm
content: Do you have the FLIR designed interface board or is it a custom interface?

author: MrSheep
author_rank: Frequent Contributor
timestamp: August 13, 2025, 07:22:50 pm
content: No I do not have the original interface board/photon board. I am a similar spot where I only have the proximity electronics. With enough info on the detector it is possible to create your own A/D converter board to process the analog data stream from your detector into digital 14bit output. From there you can convert that to Pleora or Camera link pretty easily.

author: mr ed
author_rank: Regular Contributor
timestamp: August 16, 2025, 09:30:17 pm
content: I believe all modern gas supplies are very dry and clean due to newer processing. I used to handle 2000psi o2 big bottles transfilling into smaller bottles for aviation use. Some metals will actually burn in 100% o2! Helium wont burn anything. It should be easy to refill the sterling engine just using proper hardware.

author: Liu
author_rank: Newbie
timestamp: September 19, 2025, 06:13:14 am
content: Helium filling requires a lot of professional equipment, the most important of which is the filling tooling suitable for the refrigerator. I also have a broken refrigerator in my collection, and my friend helped me fill it with helium. You also need a helium mass spectrometer that can detect the seal.