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Products => Thermal Imaging => Topic started by: eurgenca on February 20, 2021, 08:57:09 am

Title: Thermal camera question.
Post by: eurgenca on February 20, 2021, 08:57:09 am
Hello.
I have no experience with thermal cameras. I want to use it for searching a fault on pcb board with smd parts.
So my question is if is cheap chinese (150USD) camera good for this job. What kind of resolution I need?
Regards, Sebastijan.
Title: Re: Thermal camera question.
Post by: DaJMasta on February 20, 2021, 09:26:50 am
The short answer is no.

For PCB inspection you want reasonable resolution (doesn't have to be especially high, but <100 pixel a side dimensions are going to struggle unless the one part is getting much hotter than the surroundings), but most importantly you want optics that can focus up close.  Most inexpensive thermal cameras have fixed optics, and that means they are generally quite blurry within a meter or so of the camera, as they're intended for HVAC inspection or the like at longer distances.  Fewer still have adjustable optics, and especially when dealing with a small target and a low resolution sensor, you want the narrowest field of view optics you can get with the shortest focus distance to get as many of those pixels as possible on the part you want to look at..... and neither of those typically come on inexpensive cameras.


For reference, I bought a FLIR B50 camera (about 10 years old. 140x140 sensor but with a manual focus lens and reasonably up close optics) for PCB inspection and general use and paid about $450.  It wasn't an incredible deal, but it was probably a little cheaper than going rate for that level of performance, and I think before you get to $400 USD or so, it's going to be tough to find something on the market suitable for PCB inspection and as a standalone device.  If you don't mind hacking a thermal core, you may be able to get a better deal on something with analog video output and an adjustable (probably with set screws, but still) lens.
Title: Re: Thermal camera question.
Post by: eurgenca on February 20, 2021, 11:09:24 am
Thanks for quick answer.
You save me 150 USD for crap. Do you have any suggestion which model I must search?
Title: Re: Thermal camera question.
Post by: Bill W on February 20, 2021, 12:54:18 pm
How much hacking are you up for ?

See my website or posts on here about BST and 2000AS cores for example

Cores from that era can be around EUR250.  Usual source is retiring fire cameras from:
These will be at least 160x120 20Hz, mostly though 320x240 30Hz but somewhat chunky by modern standards.

Working kitted cameras are pushing up nearer EUR400+, so less saving against a 'new' cameras

Bill