Spectral Images Generation and Processing

Hi,

I’m creating a specific thread about Spectral Images Generation and Processing as a fork of some discussions started in the Notice of Meeting - ACES Gamut Mapping VWG - Meeting #2 - 2/20/2020 thread. I updated the Spectral Images Generation Computational Notebook of the aforementioned thread to mass-generate images. They are then being written to a directory on my Google Drive which is then served via Fast.io: https://academy-vwg-gm-spectral-spheres.imfast.io/ and presents the images with Jeri.

It is quite nifty as it makes it easy to compare things!

A few immediate TODOs:

  • Add Motion Pictures Camera sensitivities
  • Decide on which DSLR sensitivities
  • Decide on the lights spectrum
  • Perform IDTs computation as per the book

Cheers,

Thomas

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Here is the processing variant where an existing spectral image is used: Spectral Image Processing and also scaled to mass-generate data.

It is also served on Fast.io: https://academy-vwg-gm-hyper-spectral-images.imfast.io/

TODOs are pretty much the same than above, it might be worth sourcing real LED lights spectra, maybe @hbrendel and ARRI could provide Skypanel/Orbiter SPDs.

Cheers,

Thomas

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Hi,

Mitsuba 2 has been released a few days ago: https://github.com/mitsuba-renderer/mitsuba2

I will start looking at that tonight.

Cheers,

Thomas

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Hi,

First light with the Point Grey Grasshopper 50S5C sensitivities:

There is a related thread on Mitsuba 2 repo: https://github.com/mitsuba-renderer/mitsuba2/issues/15

Cheers,

Thomas

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Hi,

Some good progress over the weekend and I have mostly ported the Maya scene I made for Cinematic Color 2 to a pure Mitsuba 2 implementation:

Repository is here: https://github.com/colour-science/colour-mitsuba and I will add LED lights this week.

Cheers,

Thomas

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Hi,

I have almost all the pieces required now: https://academy-vwg-gm-mitsuba-spectral-images.imfast.io/



It should be straightforward to generate other images and the advantage with those synthetic renders is that now we are avoiding the clumping that was happening with the relight spectral images.

Note that the Nuke screengrab is rendered using the ACES RRT while on the website we don’t have that, you can press ? to get a list of shortcuts.

Cheers,

Thomas

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