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I have a theoretical question and i am thinking about aluminum specifically, since it due to low emissivity and high reflectivity, should appear silvery-gray in daylight conditions. When the metal has a true silvery color at a certain temperature in air in daylight, and in the case of aluminium has a very rapid cooling effect and often is many hundreds of celsius cooler immediately when poured in air compared with iron that always will keep a high temperature, then there should not be any camera effects that could turn this what for the human eye is a true silvery color, into a strong orange color?.

So i am not only talking about a natural phenomenon, that has to do with temperature and how a molten material looks when molten for the human eye. I am talking about a camera effect, if there exist a camera effect in CMOS camera sensors or with any other cameras, that can change the true color of a molten metal in daylight, the color that is true for the human eye, in this case a silvery color, into a true orange color. My guess would be that it would be impossible for a camera to change the true color of a molten silvery metal into a true orange color, and that you can find many videos with simple cameras where everything looks true to life.

If you also could be kind and tell me who the leading experts in camera psychics are, in what universities and companies i can find them, that would be great. Thanks in advance.

So i am asking, if any camera, when you film a molten silvery metal like aluminium in daylight, if the hot metal with the true color of silver, that you are observing in real life having this silver color, can turn into a true orange color on the video by some camera effect?, i dont understand how this would be possible.

I am told that "It cannot be done without post-processing.The main issue is that the camera must operate on the light received from the scene. In 3d graphics terms, this is diffuse light. It has shadows and is affected by the angle between the surface and the light. The glowing effect of molten metal is unaffected in this way. It glows equally in all directions, regardless of lighting, and has no shadows (in 3d graphics terms, it's more like an ambient light).

There is no way to distinguish between a shadow which hides part of the metal from the light and a piece of dark paper. Thus there is no way to make that shadowed region glow without also making a piece of dark paper glow the same.

Also, the heat patterns are complicated. When I was casting aluminum ingots for fun, the edges and corners cooled first. This caused the center of the ingot to glow brighter than the edges. In some lightings, the shadowless omnidirectional light of the glowing center made it look like I was seeing through the metal into the core of the ingot. I was not, of course, but they eye has to do really strange things to make sense of glowing objects, and mine decided it looked like a glow from the core.

Best bet: film the molten aluminum in a very dark environment. That will make the glowing effect more pronounced when compared to the diffuse lighting because you'll have a lower shutter speed or lower f-stop to capture the low-light scene. I created some interesting photos that way with a flash and then a long exposure while moving the camera. The flash captured the metalic grey, and then the movement created a glowing ghost that followed.

The cameras will capture the light that is present. If the light isn't present, they wont capture it. They might saturate, but that saturation will rarely result in the correct orange glow associated with high temperature metals"

Does this mean that you haft to specifically add the orange color intentially after it has been filmed in a studio with software if you want for some reason to manipulate the colors in the video?. Something that would be televised as a regular documentary or something like this would never have its video manipulated into changed colors like this, it would only be for the film/entertainment industry maybe?. What you capture on your camera and then edit for say DVD should not end up changing unless you change it specifically in the edit, as i understand it.

So i am asking if the only possible way to change the true silvery color of the molten metal in daylight with post-processing (that he is talking about) is when you intentionally add a new color with video tools and software, it will not happen by itself in some standard video process while you prepare the video for a DVD-release right?. I think both about old cameras with CMOS camera sensors and new cameras. I dont see how it would be possible for the true colors to change like that by some standard process without any manipulation with software.

I know that there are some colours/saturation values that will not be recorded by the camera - depending on the cameras dynamic range it will become white at a certain level and so depending on the cameras capability you will get a certain range of values up to where the camera sees the colour as too hot and gives a white value only. But i think for most cameras, even older CMOS camera sensors, you would need a temperature maybe above 2000 C and something like burning magnesium for a constant strong white color. If you had some pure aluminium metal powder and iron oxide metal powder reacting and producing molten iron at 1500 C and above this temp, you should have no problem seeing the orange molten iron if it was falling in the air, and if there was bright white big round ball shaped flashes in the air from the powders, the white flash would be able to block the orange molten material in the air so that you at this moment only will see the bright white flash and no orange molten material, there is nothing making this impossible on a video recording, as i understand it.

  • It sounds like you're looking for camera 'color profiles' which help a camera interpret raw data into images. I know Cannon cameras have a custom color profile editor somewhere online, and you could theoretically shift certain captured colors to other colors, eg. silver above a certain brightness value shifted to orange. Actually doing that is a little out of my wheelhouse though. – BreadEagles Feb 27 '20 at 7:14