I don't understand this "forehead elevated temperature" measurement. Most medical studies tell that fever "starts" in the corner of an eye.
You can have temperature of 38°C but forehead will be 36.7°C.
We (I mean polish team of CCTVnerds group) made tests comparing camera with forehead measurement and eye corner measurement.
@MOD I hope it's ok to post it here. If not, please delete
First two we tried to simulate "cold weather" or rainy weather so one of Nerds took cold shower. On second - another nerd put bag of frozen peas. Third video - hot eye corners vs "forehead" measurement and poor resolution.
Maybe you have some other suggestions or comments for those videos?
Yeah, most of CCTVnerds now are somehow connected with Dahua (but not only, there are people from other brands, but less active)
And I have to say - if we make trainings for sales/distributors or anyone else, we always tell that "to get best possible results you need to take off your glasses". This video where we show that camera can read temperature in mask/helmet/hat etc we use during our trainings to show that it is possible to get readig, but it's not suggested (like some sales people claim).
It's just that sometimes, some people will forget to take off glasses, or hat, or their mask, or they drink hot coffee, than it should be possible for the system to still detect best possible spot and still measure temperature.
That's why we suggest using IVSS because you can triger alarm of someone is wearing glasses or mask or hat.
But we are just small part, and not all people listen or use information and knowledge that we share. Or sometimes it's not "correct vision". That's why we post some things without logos, brands and as undisclosed.
Good question, good eye. We did not include a conclusion with Sunell on purpose because Sunell is not as clear to us as Dahua.
Dahua, criticize it or not, is really good at producing a sense of security, likely false, but still, it's very clever (and arguably very unethical) how it aggressively delivers statistically normal temperatures even on bad reads. Sunell is a bit harder for us to easily summarize.
In terms of better or worse, we are going to do a shootout next month to carefully look at each side by side (Dahua, Hikvision, Sunell, etc.) and then we can better comment on that.
Thanks for the feedback. I'll let Ethan address the blackbody specifics for Sunell but to clarify your allusion to our Dahua test, we tested the Dahua blackbody reference box in different ways and found it to not have a material impact, see Dahua blackbody variance testing.
We checked this in our testing. It was drawn larger in some examples, but in most it was tight around the blackbody. In either case, it did not impact measurement, results were consistent throughout.
Sunell looks for the hottest point inside that drawn region to reference, you can see the cursor located in the center of the blackbody region in the thermal image (You can also seen the tighter blackbody region used through most of testing).
Because the blackbody is 104°F, it would take something pretty hot to fit in that region and skew the calibration.
I personally would draw it more tightly (and have), but that's also my personal compulsion to fit a square peg in a square hole.
Given that they claim the best results are generated from looking at the camera to have clear access to the forehead, the panda appearance is actually a pretty good idea, especially when it comes to children.
My understanding is their original market before Covid was nursery and grade schools so the Panda look actually was an intentional design element. They maybe need some new options now that adults are targeted. How do we get a construction worker to look at the camera? It could get interesting.