Thermal camera for automotive diagnostics

[Toeorfinger]

Hi, I am new to this sight but have seen many eevblog videos. I have been an automotive technician for 25 years and recently saw some videos on using a thermal camera for automotive diagnostics.  I can see the benefit to this tool in many automotive applications. What I would like to know is what resolution should I be looking for in a camera? Or better yet what is the minimum resolution that would let me take advantage of a thermal camera? Snap on makes a thermal camera but I don't care for there electronic tools.  I have read about the flir E4 and a hack to make it perform better, but that seems to have been corrected in the new versions.  Are the units tha attach to your phone any good? Are there any auto techs here using a thermal camera? If so how do you like yours and if you don't mind how much did you pay for it? 
I would be greatful for any help.
Thanks Chris.
Oh by the way toeorfinger is a game from the tv show Scrubs.

[Mjolinor]

The ones that clip to your phone are all you need. Of the two common ones I prefer the Seek but I am sure that a poll would probably split preference slightly in favour of the Flir One.

[Ultrapurple]

I'd tend to go along with that general recommendation, adding only that it's well worth getting something with adjustable focus. That will make the difference between knowing "something in the fuse box is hot" and "fuse number 3 is hot".

But - and it's a big but - what sort of environment will you be working in? Clip-onto-phone imagers won't survive being regularly thrown into a toolbox; there are some much more robust (and expensive) options like those from Flir that might. Fuel, lubricants and other engineering fluids may not be kind to optics or electronics, and few affordable thermal imagers are what you'd call 'sealed'.

The good news is you don't need expensive high resolution if you have adjustable focus (or a very good depth of field). You can always move closer to see the hot bit in more detail.

[Vipitis]

Even the flir c3 isn't rugged or has any ratings for drop and water. It's a useless product anyway because the CAT S60 has the same sensor and more features (it's a full phone) for a cheaper price point.

The industrial rated cameras are really expensive.

[Mjolinor]

Before I got my Seek I bought an Argus 3 and that was truly rugged. So rugged as to be pretty useless if you were anything less than a body builder but for the £80 I gave for it it was worth buying to find out.

[Fraser]

Fire fighting cameras are definitely rugged. More recent models are also quite compact. The nice models are not that common at the moment though. I have bought some at excellent prices this year. The drawback can be their minimum focus distance as they are fixed focus and set up for room searching. Minimum focus will be 1M or more. The focus can be set to something more useful in automotive applications but this requires opening of the cameras sealed case. Temperature readout is provided on many models,  but this should be checked before purchase as it can be a option.

Fraser

[Mjolinor]

I robbed a lens out of a spare laser cutter and used blu tack to stick it on. Worked fine for close up.

[Vipitis]

I have also seen people 3D printing a auxiliary lens holder for the fire fighting cameras... But this won't be part of the ruggedness and exposed optics will take damage.

I would just get a purpose build camera and be a little careful with it.

[Mjolinor]

I have also seen people 3D printing a auxiliary lens holder for the fire fighting cameras... But this won't be part of the ruggedness and exposed optics will take damage.

I would just get a purpose build camera and be a little careful with it.

I agree. That is exactly what I did and it is cheaper. I gave £80 for the Argus 3 and got my Seek for £50 off ebay.

[Fraser]

Please be aware that Close -up lenses are only cheap and easily available if the common types used in laser cutters. That limits you to 20mm diameter and a longest FL of only 100mm. For automotive work I think 100mm will be a little too close to the 'action'

The perfect choice would be the heavily discounted Keysight (Agilent) U5855A camera as it has adequate resolution, manual focus and it is rugged. I am not certain if The Keysight factory outlet on eBay has any remaining stock though. They were around $600 delivered. I own three of them but shipping one to the USA adds expense.

Fraser

[TheSteve]

The U5855A is probably a good option - it also happens to go up to 350 Celcius which higher then a lot of other cams.

[IwuzBornanerd]

I think you should compare spec's of anything you consider to the spec's on units sold for your purpose.  Temperature detection limit comes to my mind.  I expect you would like the thing to be able to differentiate between temperatures much hotter than the boiling point of water.  If that is the case you do NOT want the original FlirOne, as if you'd want the meager 80x60 pixels anyway.  I see that the FlirOne Pro will read over 700 degrees Fahrenheit though.  The Seek stops at 626 degrees F.  I found a review of the Snap-On EETH300 thermal camera & it has the following relevant specs:

See extreme temperatures from -4 deg F (-20 deg C) to 840 deg F (450 deg C)
Large 3-1/2 inch color screen so you don’t miss a clue; 320×240 resolution
Detailed thermal images comprised of 4800 temperature zones

Beware of misleading spec's like the last 2 lines there.  The 320x240 resolution is the display only, not the sensor.  The last line is suspiciously like the FlirOne 80x60 pixels, so I suspect they use a FLIR Lepton sensor with a narrower aperture lens to get the higher temperature limit.  With only 80x60 sensor pixels I wonder if you might actually "miss a clue", but maybe it's enough for automotive uses.

I agree with the other comments on ruggedness, but if you'd like one to use at home anyway, I'd suggest getting a Seek (non-XR) & try it out in the shop a few times to see if it does what you expect.   I've seen Amazon selling the Seek new for less than $200.  But handle it only with clean hands & don't throw it in the toolbox.  Beware that you need a fairly high-end phone to run these things though.

And see if you can find a message board for automotive tech's where people are talking about the cameras and how they use them.

[Mjolinor]

The other thing in the Seek's favour is the extremely well designed box that it comes with. It can be thrown in your toolbox and I believe it is waterproof once clipped shut. It can be a dog to open sometimes and feels as though it will break but it never does.

[IwuzBornanerd]

The other thing in the Seek's favour is the extremely well designed box that it comes with. It can be thrown in your toolbox and I believe it is waterproof once clipped shut. It can be a dog to open sometimes and feels as though it will break but it never does.

An excellent point!  See photo.  But still handle with clean hands.

[Myself]

There is one rugged cellphone option aside from the Cat S60, which is the Seek Compact in the Otterbox Universe case. It holds it to the phone pretty solidly, so it's not supported by just the flimsy data connector. The Universe case is iOS-only, though, so only iphone owners need apply.

I picked one up and I love/hate it. The Seek images are jittery and grainy in a way that I'm not accustomed to (I started on a Flir E4 back in 2014 and the post-hack image quality totally spoiled me), and the app is buggy on iOS 11, which they say they should have resolved by next week so maybe that'll improve.

The case is pretty solid, though, and gives me some sense that the camera isn't guaranteed to destroy the Lightning connector on the phone if I drop it while in use. It's still pretty likely but not guaranteed.

This isn't necessarily a recommendation, but it's another contender in the field. I'm a big fan of the promise of phone-connected sensors, easy image sharing, limitless memory, remote operation, etc. None of it seems to pan out that way (my favorite phone-becomes-an-IP-camera app can't see a USB-connected camera as input, for instance), but maybe someday.

If it's purely for diagnostics and you don't need to save images to show to customers, you might get away with some of the really-cheap offerings like the TG130 or the no-brand 32x32 units coming out of southeast Asia. This can let you dip your toes in the water for about $200, self-contained, no phone required. I think I'd recommend that, with a plan to upgrade later (and sell the toy camera to another auto tech), just as a learning experience to get a sense of what you can/can't see with thermal, and decide how much you're willing to spend on the "real" one that follows.

That being said, I'm the proud new owner of yet another E4, the latest wifi version, promptly upgraded the moment I got it out of the box. I use it (and used its predecessor) in the garage all the time. Today's task was ascertaining whether the radar adaptive cruise control module was radiating while the car was parked and in accessory-on state. The module was plenty warmer than its surroundings, which is in keeping with the power draw while operating, so we concluded the transmitter was running! Definitely easier than fishing out enough of the wiring to get my clamp-meter around the B+ lead...

[PlainName]

I have bother a FLiR (ThermoCAM which cost ~£5K quite a few years ago) and i3systems clip-on. The clip-on is better resolution but, as others have noted, attaching it to a phone can be messy, and the phone needs to be very top-end to get the full frame rate. I'm using a medium expensive phone and get about 2-3fps, so it's not very useful for dynamic situations (and even focusing is a slow affair).

For automobile use I would definitely go for an all-in-one like the E4. Life is just so much simpler (which, of course, cuts both ways) and your focus is then fully on what you're looking at rather than what you're using to look at it with.

[Toeorfinger]

Thank you all for your input. There is a lot here to think about. I will take all your advice into consideration before I make a final decision. I will let you know when I do.
Thanks again,
Chris