by Chris Peterson » Thu Jun 01, 2023 8:52 pm
johnnydeep wrote: ↑Thu Jun 01, 2023 8:19 pm
So, we have "silicon in red, sulfur in yellow, calcium in green and iron in purple," and "the outer blast wave is seen in blue hues". Can anything be said from this image about what elements are in that outer blast wave? Is blue hydrogen and/or helium, or is it a combination of the other four colors? Similarly, what about the white regions?
There's a reason that science doesn't make use of colored images like this. They scramble information. In some cases, as with the Hubble palette, that information is recoverable. Because there are only three wavelengths, and they are uniquely mapped to the three physical color channels (red, green, and blue). But yellow is a mixture of red and green. So when we see yellow here, is it sulfur, or is it a mixture of silicon and calcium? Purple is a mixture of red and blue. So is purple showing us iron, or a mixture of silicon and whatever the blue channel is mapped from (which isn't stated here)?
If we were analyzing this scientifically, we'd have a full set of monochrome images, one from each filter. We would know unambiguously what was what (with some error created by the contribution of continuum sources like stars). But in an image like this? Well, we can sort of make a guess at some of what we're seeing, but it isn't very rigorous or very certain.
In general, if you have an image with no more than three source wavelengths and they are mapped to the primary colors, you may be able to determine quite a lot. More than three inputs, and mappings to combinations of primaries? Not so much.
[quote=johnnydeep post_id=331403 time=1685650799 user_id=132061]
So, we have "silicon in red, sulfur in yellow, calcium in green and iron in purple," and "the outer blast wave is seen in blue hues". Can anything be said from this image about what elements are in that outer blast wave? Is blue hydrogen and/or helium, or is it a combination of the other four colors? Similarly, what about the white regions?
[/quote]
There's a reason that science doesn't make use of colored images like this. They scramble information. In some cases, as with the Hubble palette, that information is recoverable. Because there are only three wavelengths, and they are uniquely mapped to the three physical color channels (red, green, and blue). But yellow is a mixture of red and green. So when we see yellow here, is it sulfur, or is it a mixture of silicon and calcium? Purple is a mixture of red and blue. So is purple showing us iron, or a mixture of silicon and whatever the blue channel is mapped from (which isn't stated here)?
If we were analyzing this scientifically, we'd have a full set of monochrome images, one from each filter. We would know unambiguously what was what (with some error created by the contribution of continuum sources like stars). But in an image like this? Well, we can sort of make a guess at some of what we're seeing, but it isn't very rigorous or very certain.
In general, if you have an image with no more than three source wavelengths and they are mapped to the primary colors, you may be able to determine quite a lot. More than three inputs, and mappings to combinations of primaries? Not so much.