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Comment by 20k

1 hour ago

So in your opinion, the primary thing that makes this a physically accurate simulation is that you've calculated the bending of light rays, and the structure, colouration and brightness of the accretion disk doesn't matter at all?

>As for colormapping: I follow the by-far-dominant approach in scientific literature, where color mapping choice is completely unrelated to physical accuracy of the plotted observations or simulations. Having a preference for different color schemes is a matter of taste; suggesting a linear intensity->pixel mapping is a reasonable feature request, but far from a bug or inaccuracy.

It is not true at all that this is the dominant approach in the literature, the event horizon telescope does not use this approach in their papers. I linked a comment from them elsewhere about this in a github PR

Specifically:

https://github.com/achael/eht-imaging/issues/85

>Unfortunately, vanilla afmhot does remain the current default in the eht-imaging library for historical reasons, but this could change soon. *Rest assured we thought of this issue and the paper images are indeed perceptually uniform!*

I would welcome an attempt for you to create a scale, that maps the output pixel brightness to the underlying physical luminance, which I think would show why the mapping is such a problem here from an accuracy perspective, but you're absolutely not correct that you're following the literature here. People are much more careful about presenting accurate data, and your approach would result in a correction being put out

>> I follow the by-far-dominant approach in scientific literature, where color mapping choice is completely unrelated to physical accuracy of the plotted observations or simulations.

> It is not true at all that this is the dominant approach in the literature

Just to clarify: you are saying that there are not a lot of images in literature rendered with a non-perceptually-uniform colormap (eg, any matplotlib colormap aside from the 5 uniform ones)? Or that there is only one correct way to choose colormap for a given image?