How to determine TAU's NETD level? - Page 1
Forum section: electronics / general

author: cejoba
author_rank: Regular Contributor
timestamp: November 08, 2022, 01:52:25 pm
content: Hi.There seems to be 3 different NETD for TAU2:https://www.flir.com/products/tau-2/Industrial: <30mK Performance: <50 mK Commercial: <60mKHow can I tell which level does a particular unit have?Thanks.

author: Fraser
author_rank: Super Contributor
timestamp: November 08, 2022, 05:34:29 pm
content: The version you have is detailed in the cores serial numberSee this data sheet and the key to the serial number…https://www.unmannedsystemstechnology.com/wp-content/uploads/2012/04/FLIR-Tau2-Brochure.pdfI attach a picture of the TAU2 serial number key and an image of one of my TAU cores. The performance indicator is the same on TAU and TAU2 cores. Expect to see C, P or I in that location depending upon version.Fraser

author: Bill W
author_rank: Super Contributor
timestamp: November 08, 2022, 05:58:57 pm
content: Those are maximum NETD, what any one unit has would only be on the original test sheet.In reality the NETD will be roughly on a normal distribution, and the price / performance points chosen to avoid losing any detectors.If things were going well in manufacture, a fair percentage of the 'commercial' will be around 45mK.

author: svgurus
author_rank: Regular Contributor
timestamp: November 09, 2022, 12:59:43 am
content: Have anyone ever seen I letter in this SKU?) there is also R, its P with additional measuring functions that I's always have.

author: cejoba
author_rank: Regular Contributor
timestamp: November 10, 2022, 01:50:49 pm
content: Quote from: Fraser on November 08, 2022, 05:34:29 pmThanks you!So you mean part number instead of serial number.Strangely my core's sticker don't have that line.I'll try to see if I can get that from RS232.

author: Fraser
author_rank: Super Contributor
timestamp: November 10, 2022, 02:32:16 pm
content: Sorry, yes part number.The cores part number and resolution is displayed in the bottom right corner of the TAU PC GUIFraser

author: cejoba
author_rank: Regular Contributor
timestamp: November 12, 2022, 01:04:30 pm
content: My part No is "427-0070-21-00"...What does that mean?

author: Fraser
author_rank: Super Contributor
timestamp: November 12, 2022, 02:22:42 pm
content: That part number appears to be for a CCTV camera. Looks like FLIR use the CCTV camera part number for the TAU within it.The TAU specs will be that of the specific CCTV camera.Fraser

author: hap2001
author_rank: Regular Contributor
timestamp: January 23, 2023, 01:53:46 pm
content: Is there any real world performance difference between TAU324(25um) and TAU336(17um), despite they have same NETD on paper?

author: IR_Geek
author_rank: Regular Contributor
timestamp: January 23, 2023, 11:02:49 pm
content: Quote from: hap2001 on January 23, 2023, 01:53:46 pmAssuming you have optics that provide the same resolution, then no. When I say resolution I'm not talking about the geometrical Instantaneous FOV (IFOV), but rather the actual blur. If you want to dive deep into the weeds, then look up MTF (modulation transfer function). Two systems with matching NETD's and MTF are effectively identical. With that said, you typically pay a price in size, weight, and power for larger pixel systems.FYI - I can't stand NETD when used for modern systems. Maybe a good threshold metric, but doesn't really tell you anything about the sensor. 3D Noise is the better metric but harder for people to understand.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: January 23, 2023, 11:38:20 pm
content: Or you could just measure it. You will then know the sensitivity of your camera, and perhaps have a strong clue about which class yours was sold as.https://www.flir.com/support-center/Instruments/how-is-nedt-measured/This is among the simpler methods, much better than the old "3 monkey" method.While doing a very precise measurement requires a very good black body, it isn't terribly difficult to create one for this method that can get you errors in the 10% range, typically better. Review other threads in this area for the best choices of paints, read up and understand the principals of cavity black bodies and think carefully about how you will do your heater and how the heat will be spread. In the olden days part of the expense of a good black body was being able to know the temperature accurately. These days accuracy to a fraction of a degree C is virtually free. Remember while setting up your black body that stability is more important than absolute accuracy.Don't just plug your data into the equation and be satisfied. There are many things going on in these systems that can be seen by carefully going through the raw data.

author: hap2001
author_rank: Regular Contributor
timestamp: January 24, 2023, 11:00:01 am
content: Quote from: IR_Geek on January 23, 2023, 11:02:49 pmYeah, that's why I asked the question. They just slam "50mk" on every brand and model, while they perform really different.