Visual Effects: VFX Requirements & Best Practices
The exchange of images between a finishing facility and VFX vendor(s) is a crucial aspect of post-production which has a large impact on the quality, schedule, and cost of VFX. The following requirements and best practices are intended to reduce ambiguity, maximize image quality and reduce errors during this process. These requirements are based on experience across many types of content and workflows, but the best choices for each project may depend on a number of factors. If you have any questions, Netflix is here to help. Please reach out to your Post Management or VFX contact at Netflix.
- VFX pulls and deliveries must have an intended active image area of at least UHD (3840 square pixels in width).
- No upresing allowed.
- If original capture format was less than 3840 square pixels in width, contact your Post Management or VFX contact at Netflix with any questions.
- VFX pulls and final deliveries must be in one of the following file formats:
- 16-bit EXR (.exr) if color pipeline is ACES, or if the pull color pipeline is set to a Camera Linear color space (such as Linear AWG / Alexa Wide Gamut).
- EXR can be uncompressed or use lossless compression (i.e. ZIP or PIZ).
- 16-bit DPX (.dpx) when the pull color pipeline is set to a Camera Log color space (such as LogC).
- 10-bit DPX (.dpx) ONLY when the primary capture format was 10-bit Log.
- LOG EXRs will not be accepted.
- Framing charts must be shared between all vendors to ensure resolution and framing consistency and pixel-for-pixel accuracy throughout the entire imaging pipeline.
- Please contact your Post Management or VFX contact at Netflix if you feel you will have any issues fulfilling this requirement.
- Color pipeline must be established and communicated to all vendors.
- Round-trip tests between VFX vendors, editorial and the DI vendor must be performed early in the process to verify color pipeline consistency.
- Please visit "Color Pipeline" for more detailed requirements.
- VFX pulls must include dailies color reference (Quicktime or reference frames) along with any CDLs and/or LUTs used in the dailies process. This is to help ensure that editorial proxies of VFX shots can easily be matched to the original dailies proxy.
- Proxy or intermediate Quicktime files must be used only for reference during editing and work-in-progress reviews, and not for final delivery or inclusion in the conform.
- A framing chart per sensor mode should depict the exact resolution that the sensor mode will capture as well as the intended active image resolution(s). VFX can work with the camera department to capture these charts.
- Shooting lens distortion charts, per lens type, per sensor mode for VFX vendors is strongly recommended during camera testing, especially when a significant amount of 3D tracking is anticipated. VFX should provide lens grids and work with the camera department to make sure they are captured appropriately.
- To avoid debayering inconsistencies, it is recommended that pulls are debayered and exported from DI facility or a dedicated vendor who is aligned with the DI facility’s pipeline and set up.
- The pull facility should debayer pulled plates to a standardized color space (such as ACES) that will allow CDLs and LUTs to apply in a way that is consistent with the dailies color pipeline.
- While we do not encourage it, if the plates are to be in a mix of camera colorspaces, then the different colorspaces should be clearly communicated by the pull facility per plate and must be tracked.
Aspect Ratio, Cropping & Scaling
- All vendors should align with the Post and/or VFX Supervisor with any plans to crop/reframe material.
- Methodology for scaling should be standardized across vendors to ensure pixel-for-pixel consistency (i.e. resize filters, order of operations, etc).
- Framing charts should demonstrate the scaling and cropping operations for each type of plate resolution vendors will receive.
- Vendors should be given step-by-step instructions on how to get from any plate resolution to the final delivery resolution.
- VFX should be aligned with DI facility if the finishing pipeline will be in a squeezed or un-squeezed format.
- The working resolution should be equal to or greater than delivery resolution.
Color Grading Plates/Pulls
- Pre-grading plates prior to delivering to VFX vendors is discouraged and should never be baked in. If a pre-grade exists, it should be delivered as a sidecar file (such as .cc or .cdl).
- If required by VFX vendor, any balancing or neutral grading should be performed using debayered plates in a scene-referred colorspace, and corrections should be limited to reversible non-destructive operations, such as the ones that are available in CDLs (slope, offset, power and saturation).
- Editorial should provide proxy media format requirements for VFX proxy media that is to be delivered by the VFX vendor for inclusion in the offline project.
- Please note that this format may be different than the format requested for studio reviews.
- The DI facility may be consulted to provide detailed instructions on how to render proper color into proxy files accurately.
- In a color managed pipeline, this most commonly involves applying CDL and LUT in the defined working color space in order to match original dailies color.
VFX Delivery, Archival & Wrap
- VFX vendors should be provided with specs for the final delivery format for the DI facility, including the image container (i.e. DPX, EXR) and compression type (i.e. uncompressed, ZIP, PIZ). The production team should confirm these specs with the DI facility.
- Final delivery to DI should be submitted as ungraded shots.
- The VFX Producer, VFX Supervisor, or Post Supervisor should ensure that final deliveries are in alignment with the documented post specs on their show to ensure that any final VFX shots will align in quality to non-VFX shots in the DI.
- VFX material should be uploaded directly to Content Hub Workspaces using a folder directory as specified by your VFX Operations contact.
- For Series, archival material can be delivered throughout the project as episodes are finalized via Content Hub.
- If there are VFX shots containing texted graphics, project files for those shots along with textless versions and accompanying mattes , if not already embedded, may need to be provided to help with localization. Please confirm with your post production supervisor to see if this is a requirement on your production.
- Article title changed from "VFX Pulls (One Sheet)" to " VFX Requirements & Best Practices"
- "Requirements" section has been expanded to provide more detailed information.
- Added "Best Practices" to provide guidance in and around a number of areas e.g. Camera Tests, Editorial etc.