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I have a used FLIR ETS320 thermal PCB inspection camera on its way to me
This camera is a specialist product produced by FLIR to meet the needs of the electronics design, production and repair industries.
It is far from a perfect solution as we shall see. It is my intention to improve the unit once it arrives.
I have studied the design and watched Dave's video's about the unit. One is a review and the other is a teardown.
They may be found, along with the associated discussions about the unit, here:
https://www.eevblog.com/forum/blog/eevblog-988-flir-ets320-benchtop-thermal-camera-review/msg1194401/#msg1194401
https://www.eevblog.com/forum/blog/eevblog-989-flir-ets320-thermal-camera-teardown/msg1195706/#msg1195706
My views on this units flaws follow:
1. The ETS head is attached to what can generously be described as a budget Chinese Microscope stand. This camera costs £2000!
2. It is of note that the manual details how to remove the head from the cheap stand and rack, in order to fit it on a better stand maybe ? Why else would they detail such ?
3. The ETS320 contains a virtually unmodified E8 camera chassis. Just a mount for the Lithium battery fitted where the LCD display normally sits. Even the USB socket remains in its original position. A short patch cable is used to relocate the micro USB port to the rear of the head.
3. The standard Ex series lens assembly is used. A custom lens assembly for the ETS would have made it far more versatile. Why no focus control ? I can make such with my 3D printer so why did FLIR not have a focus ring adapter fitted for manual distance focus ?
4. The head is fixed in a downward staring position so, unlike video presenters, it cannot rotate its head to look horizontally. A nice option in some cases and it would have made the unit capable of being a standard desk mounted thermal camera if the focus was adjustable.
5. FLIR could have provided different lens options, including a true microscope lens option rather than a wide angle Ex series lens.
I think I can answer most of the above ..... the ETS320 appears to be someone's 'bright idea'. Take an E8 chassis and bolt it on to a cheap microscope stand, reposition the LCD and voila, a thermal PCB inspection unit using standard FLIR production parts plus a custom case moulding. Nice and cheap to produce. It could almost have come from someone's hobby workshop ! It fits the stated purpose, but only just, and versatility has been lost through lack of proper product development. It looks like a fast track 'quick win' solution to fill a gap in the market.
The good news is that they chose to use the full 320 x 240 resolution of the microbolometer so no hacking required (I may well hack mine though ) They also made it relatively easy for me to attach it to a better microscope stand and to make the lens focus adjustable. I am also hoping to achieve true thermal microscope capability with an auxiliary lens. I can then study insects and tiny electronic components with it
The ETS320 is normally shipped with FLIR Tools+ but I suspect that has gone walkies from my used unit. I already have a FLIR Tools+ licence and FLIR ResearchIR so no worries on that front
It will be an interesting little project to work on. It is a specialist product but I think I can make it far more versatile with some minor modifications. My 3D printer could prove very useful for making custom parts and adapters etc.
What follows are my plans for said improvements and modifications to the ETS320 'System'. Some parts I already have, some have been ordered and some I will make using a 3D printer.
Fraser
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Upgrade 1
Improved stand
The stand provided with the ETS320 is basic with only two axis of movement, namely up/down and left/right swing movement.
I already own a better quality microscope base and 25mm diameter vertical pole. In order to improve the versatility of the ETS320 I have purchased a horizontal boom arm with a knuckle joint end onto which the camera rack head mounts. The boom arm provides the ETS320 head with five axis of movement, namely, Up/Down, Left/Right, forward/backwards, knuckle tilt up/down and rotation.
The combination of a decent base with a boom arm and knuckle end will enable the camera head to be positioned to meet specific imaging situations. It will be far more useful than the standard simple stand.
FLIR even detail in the user how to remove the ETS320 head unit from the focus rack assembly. It is as though they knew that the basic stand was restricting the units versatility and owners would want to attach the head to a better stand. Having analysed the pictures of the ETS320 I noted, what appear to be sleeves fitted in the stand vertical pole mount. The stand uses a 21mm pole but I suspect the sleeves raise this to the other standard which is ~25mm. Thankfully this enables a standard boom arm to be used with the heads rack. There is therefore no need to modify or replace the head focus rack assembly. It is simply removed off of the supplied base and slid onto the boom arms knuckle mount pole. This has yet to be proven in practice, but the odds are good that the rack assembly will fit onto the 24mm knuckle pole
Fraser
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Upgrade 2
Lens manual focus
The standard ETS320 has a fixed focus lens that is the same as that fitted to the Ex series cameras. Its focus point is centre on a 70mm distance to target, with a 20mm total depth of field. This provides a useful distance to target of only 60mm to 80mm. Not very impressive. The standard closest focus distance of 60mm provides a minimum target size of 170um per pixel.
As owners of the Ex series cameras will already know, it is relatively easy to manually adjust the focus on a Ex series camera. You just need a suitable 'focus tool' that fits into the plastic lens mount recesses. There are several designs of Focus Tool available for 3D printing. A look on Thingiverse reveals several choices of design. I have printed then all and presently have one in mind for the ETS320. If possible it will be a firm press fit, but removable fro fitting auxiliary lenses.
With a manual focus tool fitted it will be possible to set the focus for best image anywhere between a few cm and infinity. Very useful when using an adjustable boom arm. In the standard 'rig' the ETS320 can only image a relatively small area of the PCB beneath its head. By having adjustable focus, the head may ne moved much further away from the target and the focus set accordingly. Thanks to the boom arm, the head can even be rotated 90 degrees for horizontal viewing of targets in the near or far field.
Pictured Focus tool on Thingiverse:
https://www.thingiverse.com/thing:188896
Fraser
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Upgrade 3
Auxiliary lens
The standard ETS320 uses the Ex series camera lens that is set for close focus. It is not a lens designed for very close working or thermal microscopy. The options for better close-up capabilities is limited only by budget. As is known by owners of the Ex series, an auxiliary (aka Supplemental) lens may be placed in front of the cameras objective to achieve close-up focus. The minimum focus distance is set by the auxiliary lens specification. Common ZnSe CO2 laser cutter lenses out of China come in several FL's. Common FL distances are 25mm, 50mm, 63mm and 100mm. The 63mm and 100mm lenses are quite versatile for close PCB inspection. I had considered using a close-up auxiliary lens on the ETS320, but manually focussing the lens achieves better results and I intend to use manual focus so nothing is gained.
I have in mind far greater auxiliary lenses for the ETS320. Namely a thermal microscope capability ! Sadly thermal microscope lens blocks are not a common and affordable item ! A good friend, Bill W, once told me about using a standard lens block as a microscope lens by reversing it and using it as an auxiliary lens in front of the cameras standard objective. The cameras standard lens is set to focus at infinity and this matches the output of the reversed lens block.
This technique is used in visible light photography where two approaches are used. Replacing the lens block with a reversed lens block, or adding a reversed lens block to the front of the standard lens block. We are looking at the latter case here.
In a perfect system the optical system works as follows:
If two identical lens blocks, with FL 7mm, are attached 'objective to objective' a 17um pixel on the microbolometer, located at 7mm back focus distance, will image a target 7mm away from the rear lens element of the reversed lens with a spatial resolution of 17um per pixel ! You effectively have a camera with the same spatial resolution as the microbolometer pixels size.
We do not live in a perfect world however and the two lenses need not be identical. The lens block resolution will also restrict the available spatial resolution in this design.
I am actively hunting a suitable lens that I can reverse in front of the ETS320 objective to form a camera with a close to 17um spatial resolution. The area observable on the target by such a lens will only be around 5mm x 4mm at 7mm distance. Mounting it will need some thought, but I am thinking my 3D printer will probably assist me in this area.
Fraser
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Perhaps the reason why they used an E8 is all because of this very forum! You could say that FLIR had tons of E8 stock remaining, as everyone was buying E4s and hacking them! Why not just repurpose them?! One can wonder!
Anyway, great bargain and I look forward to seeing the modifications in situ! -
The E8 guts found inside the ETS320.......
The sharp eyed will notice that the Wi-Fi socket position is populated. it is interesting that FLIR chose to not fit the Wi-Fi module in this unit. A good reason for this wise move might be the desire to avoid RFI from the transceiver to the DUT. Wi-Fi is also banned in some research and production facilities on grounds of security and a controlled RF environment.
Fraser
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The new boom arrived today.
I bought a Chinese 'no-name' boom as it appears adequate for the task. It came with a microscope rack focus mount as well but that is not needed for my upgrade. I was fortunate to find a seller in the UK who was selling just the boom and microscope mount as I already have a nice base assembly.
Fraser
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I have just received a beautiful, finely engineered thermal lens block and lens mount flange for this project.
My sincerest thanks to my benefactor
He knows who he is
The lens block is designed for a professional thermal camera and makes the FLIR Ex series lens block look like a toy, yet they both share very similar fields of view. Perfect for this project.
The Aluminium cylindrical shell of the lens block is threaded along its full length and measures a diminutive 20mm diameter x 12mm long. Due to the full length fine thread, it is easy to reverse the lens in the mounting flange.
I know I am likely 'sad', but I love fine engineering and this little lens block is gorgeous. I suspect it would normally be found in a high end small thermal observation scope or similar.
Fraser -
Another element of my experimentation with the ETS320
Not my work, but that of Joe-C who has very kindly allowed me to use it in my project. He has done a lovely job of the design.
Can you guess what it is hiding under its support material ?
This is just a draft print as I will need to adapt the design to better meet my specific needs.
The 'reveal' will be later tonight
Fraser
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Reveal time
The 3D part shrouded in support material is a new lens holder that may be used in place of the original fitted to the FLIR Ex / ETS320
This enables me to experiment with different objective lenses. It could also be extended to enable easy fitment of the reversed lens for microscope work. The lens holder was designed by Joe-C and he has kindly shared it with me. Joe-C has saved me from a steep learning curve with CAD software designing fine threads ! Thanks Joe
These ABS prints were created on my UP! Box printer. They are 'normal' quality and really just draft prints for the moment. I can use a fine print setting and 0.1mm layers to improve the quality further for the final prints. I am pretty pleased with these 'rough' prints though. The lens holder on the right was just lightly finished with a file to take off the edges, top and bottom.
Fraser
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I just printed the lens holder with 0.1mm layers and 'Fine' print quality setting in the driver software.
The result is far better definition in the fine threads and a better overall finish to the part
The part is so small that it prints in under 30 minutes in the highest quality setting and only 15 minutes in 0.2mm layer/'Normal' setting.
Fraser -
You should do some example shots of how different lenses improve the image quality.
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Hopefully that will be possible once the ETS320 arrives with me. It is due sometime this week.
The challenge I face is a combination of two factors, namely lens block diameter and lens back focus distance. Both if these need to be compatible with the ETS320 metal chassis that holds the lens block
With regard to auxiliary lenses, that is far simpler as the lens just needs to be mounted in front of the normal FLIR Objective.
If I use a non original objective lens block I am also likely to encounter some calibration issues. I have a decent Black Body thermal source so can test for calibration error and gradient across the lens.
My intention is to end up with a manual focus lens and a thermal microscope auxiliary lens that can attach to either the objective housing or the ETS320 casing in some neat fashion. This may provide a pixel size on target of as little as 17um. That is ten times better than the ETS320 standard specification
I will likely not need a general purpose mono element close-up lens if the objective manual focus works out OK. I will try some Thorlabs Germanium Close-up lenses with an FL of 15mm to see how they perform in this role though
Fraser -
Having revisited the issue of the standard FLIR Objective lens and its mounting, I am more and more inclined to scrap the FLIR lens block casing and replace it with something better.
The FLIR Ex/ETS320 lens block appears to use a M13.5 x 1mm thread. Sadly not the usual M12 x 0.5mm 'S' mount thread found on cheap CCTV cameras. I am considering fitting a M12 lens mounting ring to the ETS320 metal chassis and adapting a common M12 type CCTV lens block housing to take the FLIR lens element. The common CCTV lenses offer the advantage of a standard 'S' type mount, a metal lens block casing and a 0.5mm thread pitch.
I can then easily create an 'S' mount lens with a long enough body for manual focus and attachment of the microscope auxiliary lens. I attach a couple of pictures of promising 'S' mount CCTV lenses that might be adapted to the requirement. A key stumbling block may be the diameter of the original FLIR lens element as I need to fit it in a M12 threaded cylinder.
Fraser
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The FLIR ETS320 has just arrived
The unit has been partially disassembled for reasons not known. It could have been a review unit or part of a trade stand display ? It is also possible that someone was looking into the design as it is a unique product in its market segment. I am assured that it still works perfectly but could not be re-assembled into its case. Dave had the same problem when he disassembled his review ETS320.
The re-assembly problem surrounds the short LCD ribbon cable. It is the same assembly as used in the Ex series but the different case design makes it extremely difficult to re-connect the LCD display ribbon cable once it has been removed from its ZIF connector. The ZIF connector easily releases the ribbon during dis-assembly though. At the factory, the LCD panel was fitted after the case lid had been attached to the unit. Dave had to release the display glue to copy that process. I intend to extend the LCD display ribbon with an FPC extender cable. That will provide enough length to reconnect the LCD display without having to unglue it every time I open the units case.
The unit is in very nice condition and was described as 'new' which is interesting. Hence my thoughts about it being a review model or similar. Most parts are present. I say 'most' because the rubber surround to the lens area is missing. All other parts are present, including all the screws (a minor miracle
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The stand is exactly as I expected, a cheap Chinese affair, not worthy of a serious industrial design. I have identified it on ebay and it costs around £40 including the microscope holder and focus rack. Cheap and cheerful sums it up well.
The actual FLIR camera head is an acceptable design and build quality. A true industrial tool would have had a cast metal casing, but then I believe FLIR was building this unit down to a price to fill a gap in the market.
The camera chassis is, as we already know, a Ex chassis with a battery holder and adapter PCB mounted where the LCD display would normally be found on the handheld camera. A reasonable adaption of a standard Ex series production assembly.
Now the mistake that FLIR made for reasons unknown..... the Lens block. This is just a bog standard Ex series lens block. Why on earth FLIR did not design a new manual focus ring lens block carrier or even attach a manual focus ring to the standard Ex part, I do not know. Such a silly oversight as it would have made the unit so much more versatile. I will sort this out on my unit. Manual focus of that lens is, IMHO, essential in this application.
If anyone has a spare of the rubber molding that surrounds the Ex series camera lens, I would be interested in buying it. I know some forum members have stripped their Ex cameras for use on Drones so thought I would ask.
OK, enough comment from me for the moment..... to the pictures.......
Fraser
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Pictures continued.....
Note that the Ex Chassis is fitted with both the visible light camera and Bluetooth module connectors.
Fraser
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Pictures continued....
As suspected, the rack assembly pole mount is fitted with nylon spacers, top and bottom. These just unscrew.
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I have just looked at Dave's ETS320 teardown again. I was incorrect in my assumption that the Ex series rubber moulding is used in the ETS320. Whilst the plastic casing appears designed to take it, Dave's teardown shows just a rubber 'O' ring seal around the lens mount. I can fabricate such a seal quite easily.
Fraser -
Looking at the additional PCB that serves the keypad, I am struck by the number of unpopulated 'diode' positions that are present on the board. Obviously a 'just in case' inclusion in the PCB design
Regarding the lack of a Wireless transceiver module.......
The unit is not fitted with a Wireless communications transceiver, and for likely good reason. It does have the Wireless transceiver header fitted though. RFI is not something you would want to inflict upon a DUT when it is likely that screening covers have been removed for component visibility under the camera.
First minor setback..... the drop arm on my new boom arm is 1mm, yes 1mm, too big for the pole hole in the camera rack mount (with nylon spacers removed)
Such is life. I will either reduce the diameter of the drop arm on my lathe, or fabricate a new one from aluminium bar.
Fraser
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I have fired up the camera chassis on a USB link to my laptop running FLIR Tools.
All is well. The camera is working perfectly and producing nice images.
I discovered why Dave could not extend the focus distance during his review. FLIR have installed three thin 'O' rings on the lens block thread. These prevent the lens block screwing in to the distance found on the Ex series. I do not think this is an effort by FLIR to prevent distance focus, it is most likely a very simple method of 'locking' the lens at the correct focus distance whilst allowing a small amount of focus movement through compression of the 'O' rings. I removed the three 'O' rings and this enabled full focus range from Millimeters to infinity. The thread on the lens block is quite loose and there is no thread locking ring or built in friction strip to hold the lens at a set point. I never did like the Ex series focus block design. That view has not changed. Even the cheapest 'board cameras' from China likely have a better lens block thread design ! Not good FLIR
Whilst running FLIR Tools in live stream mode I captured a test image of my TV to see if all was working as expected. I attach a PNG version of that image.
The camera is loaded with Firmware 3.5. I will likely upgrade that to version 3.9, but not 3.12 !
All is looking good so far
Fraser
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The testing of my draft 3D prints for the focus tool and lens block housing has proved them to be fit for purpose.
The 'Joe-C' Ex series Lens block housing is a good fit, with the same amount of slack in the threads as the original FLIR part. I could make it a tighter fit by slightly increasing its diameter.
The lens focus tool from Thingiverse fits perfectly. It is a nice snug fit and retains itself in the lens housing recesses very well. Much better than I had expected The focus tool will likely be adapted to form a focus ring that remains attacked to the FLIR lens housing.
Fraser
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Focus tool.....
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On the boom arm front........
The focus rack mount that comes with the ETS320 is the same mediocre quality as the stand on which it mounts. No surprises there as it is supplied from the same source. It even lacks a tension adjustment. That combined with its non standard pole hole diameter and crude 'bare screw' pole securing method does not endear it to me.
Thankfully the new boom arm I purchased came with a better quality rack and microscope holder assembly. It has a higher quality feel to it and includes a tension adjustment. It also uses a proper compression band to secure it to the pole. At this point in time I am looking to modify this rack mount assembly to mount it on the ETS320 camera head. It is not a difficult task but needs to be done with care to maintain the quality feel of the mounting.
Fraser
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Hi Fraser,
nice progress
i split the Lens from my Case Project and made some changes for better handling.
the previous design was small to prevent Visual interference (Visual Camera near to Thermal Lens).
Now it is better to handle i guess... but its only a "shoot in the blue", you maybe have to improve it.
The zip contains the Freecad project file and a stl model.
Good luck.
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Dear Joe-C,
Thank you so much for taking the time to do this for me. It is very much appreciated
Best Wishes
Fraser