January 21, 2022

Present

• Michael Min

• Nick Porcino

• Joseph Goldstone

• Michael B Johnson

• David Stump

• Alexander Schwank

• Sam Richards

• Kevin

• JT Nelson

• Patrick Palmer

• OT

• Sergio Rojas

• Quentin Birrer

Discussion

Joseph Goldstone

Should there be a fallback for a pinhole model for simple use cases?

usd

- modularity

- well engineered

- established across interested users

questionnaire

- assess sophistication at facilities

- assess rigor vs seat-of-the-pants

- identify precision needs datum by datum

- can camera and lens information be teased apart?

- are we stuck with grids?

- working practice should guide metadata collection

- this is an opportunity to be precise in a shared manner

- too much for OpenEXR

- usd should be the place a common model is canonically expressed

- this effort is user-pull, not vendor-push therefore serves the community

- the original camera parameterization equations we use came from JPL and the Mars Rovers

- there needs to be a procedures manual on characterization and recording the data

- think spectrally, act colormetrically

David Stump

- it's not critical to get it correct first time

- it should evolve as the metadata is used and adopted

- an adoption bell-curve phenomenon, time is ripe to do this, finally

- producers won’t care about the data, they will care about cost-savings

- industry resists efforts with self-interest. Absence of profit motive makes this effort compelling

- coefficients for third order equations characterize lenses, easy to evaluate

- has json data for lenses from Cooke, can supply these for usd camera wg to use

Sam Richards

- usd could be used for overlays with take to take variations

- Cover email to be sent to heads of match move by TC members: 

https://docs.google.com/document/d/1Hnmr8kIiT6VzR0HEVlsO_cK-I15K2Xu4xWVqjLUL0c8/edit?usp=sharing

- Video for commandante:

 https://drive.google.com/file/d/1ERDD5w5vxn3XGFkP00GgOriio9291pld/view

- grid tests should be used to wedge the numeric characterization

- Joseph will send Sam the Cooke Part Three document to share with this group

   Here it is https://bitbucket.org/cookeoptics/cookelensmetadata/src/master/Documentation/Cooke-i-Technology-Part-III-2021.pdf

Michael Min

- accepted workflow is to matchmove approximate data

- trying to break this mold

- a cost savings would accrue if a shared camera model started to supplant match moving

- can we identify a base model in cooperation with camera vendors

Michael B Johnson

- compositional architecture of USD makes it appropriate for scalable data

- layering of data allows variation, levels of detail, and external referencing

- USD is descriptive, not evaluative

The camera data is contained, but there’s no functionally-derived data elsewhere

- can UsdShade be used to make an evaluable graph of camera parameters?