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people sometimes show photos like this

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one and say that it shows molten metal

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and they claim this is because of the

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color that you see here we see something

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that's orange in yellow and they say

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that the color here indicates this is

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molten is this actually true though I

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decided to do some experiments to find

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out so you probably a chart like this

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before it's showing the whoops what

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color iron or steel should look like if

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it is a certain temperature temperature

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in degrees C you see when it's being

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red-hot it's about 500 plus degrees C

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orange topped is like around 950 here

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and white hot as 1300 degrees C and it

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melts around 15 something so these would

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be very very hot here yellow or white is

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quite hot now I noticed earlier that

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when I was looking at this through the

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my phone camera it looks different to

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what I was actually seeing so what I've

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got is my temperature probe here which

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is I'm gonna heat with a torch and I've

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got it plugged in so I can see how hot

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it is and I've got another camera over

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here which is going to record what it

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actually looks like now I've set the

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exposure down to stops there and that

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will hopefully give a better

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representation of what it looks like I'm

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going to point to this chart as to where

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I think the temperature of this is

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visually so let's give that a go all

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right we can see everything there I'm

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just gonna use this torch here to get is

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quite hot enough now let's see what

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all right now its temperatures going up

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600 degrees C and it's already kind of

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orange I put it around maybe here still

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kind of orange bright orange maybe we

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were around here see like the

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temperature is like eight hundred and

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something here which will be down here

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what I'm seeing is a brighter orange if

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I take this off mmm it's kind of goes to

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that pretty much straightaway let's see

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if we can get it to be a bit a bit

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brighter

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all right that's around about here still

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alright that isn't gonna get much hotter

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than that so I'm gonna try using a more

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powerful torch thank you little touch

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here we got the map Pro touch I'm going

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to spray you the very loud audio there

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he couldn't really hear me talking but

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what I was saying here was basically

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that that what I'm pointing to 1100

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degrees matched the thermometer and as

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you can see it also matches the close-up

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video it didn't get white-hot and it

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took a while before it really got bright

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yellow it seemed to lag a little bit

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behind being more kind of very bright

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orange bright yellow than then getting

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towards any kind of white hotness and it

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didn't look like he was melting at all

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he doesn't like a blob you can kind of

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see it looks a bit like a blob in in the

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video of the iPhone video but it looked

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very clear as you can see in the

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orange mmm Stiller is very quickly down

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already so what can we learn from this

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firstly that the color you see by eye is

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a pretty good indication of temperature

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although in this light you can't really

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see the dollar reds but it works very

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well for the orange to white heart range

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secondly any video or photo of a small

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glowing object greatly exaggerated s--

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the brightness above red-hot and so it

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makes it looks a lot hotter than it

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really is we can see these most clear at

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the end here while the torch is still on

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the probe when I correctly identifies

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the temperature as in the upper part of

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1,100 degrees C and the close-up

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underexposed video also matches as well

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however the phone camera shows it as

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white-hot second later I remove the

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torch from the iPhone perspective it

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looks like it's a molten blob of white

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hot steel but to my eye and the close-up

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camera we can see it's just yellow hot

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not close to molten at all as it cools

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down we can see it matches well by I and

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my close-up as it drops below a thousand

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degrees it's now orange hot but my phone

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still thinks it's white hot on the end

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only when it drops below 902 Gries does

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the phone color start to match what I

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see so the lesson here is color

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temperature and photos and videos is

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greatly affected by the overall lighting

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and exposure and small orange hot

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objects at 950 degrees C can look like

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the white hot at over 1,300 degrees C or