Format Support

ISO 12800 value

A new 12800 ISO value is now available in the Colour menu / ISO list.

R3D Bit Depth selector

It is now possible to select the working bit depth when working with R3D files (regular or HDRx files):

• 12-bit (Default)
• 16 bit fp: 16-bit floating point

When selecting the 16 bit fp option, the Gamma Curve setting is automatically set to Scene Linear (16bit fp) to keep it scene-referred and not prematurely tone-map the floating-point image.

R3D transcoding to OpenEXR files

It is now possible to select OpenEXR as a transcoding file format (in the Output menu). The resulting transcoded media will be 16-bit half float RGB files.

HDRx support

The Red Epic camera is able to record R3D files in two modes: standard and HDRx. The HDRx option allows the recording of two exposures as video tracks within the same R3D file. When you import HDRx footage in Lustre, there are new settings in the Format menu to select how you want to use the two exposures.

Format / HDRx Settings

• Primary Exposure: this is the main exposure of the R3D file
• Highlight Exposure: this is the second exposure of the R3D file.
• Blend Exposure: this option allows you to blend the values between the two exposures to create a single image for grading. This option uses both video tracks of their R3D file. Playback performance may be altered.
• High Dynamic Range: this option converts the two exposures into a 16-bit half-float image. When this option is selected, the Debayering / Bit Depth option is automatically set to 16-bit fp and the Gamma Curve setting is set to Scene Linear (16bit fp).

HDRx High Dynamic Range Options

• Blend: Set a value to blend the two exposures of a RED HDRx clip.With HDRx Settings set to Blend Exposures, this field behaves like the blend in REDCINE-X. The blend operation is a blend of the two exposures: -1 shows only the Highlight (X frame), 1 only the Primary (A Frame), and 0 a 50-50 mix. With HDRx Settings set to High Dynamic Range, Blend also attenuates the artefacts created by scene motions. Set to 1 unless you are troubleshooting motion artefacts.
• Exposure Offset: Set how much greater the Primary exposure was compared to the Highlight exposure, in units of stops. Only available when HDRx Settings box is set to High Dynamic Range. The Exposure Offset should be set to match the setting on the camera for how many stops separate the Primary and Highlight tracks. This is typically 2 or 3 stops. Enter the same value used to record the footage or you will get bad results.
• Highlight Threshold: Set the threshold when pixels from the Highlight exposure are used instead of the over-exposed pixels from the Primary exposure. Only available when HDRx Settings box is set to High Dynamic Range. Set Highlight Threshold last because import options such as ISO or FLUT lighten or darken the image. Too high and you get clipping (often including a magenta-coloured cast), too low and the midtones and shadows have noise leaking in from the Highlight track.

A Technique to Set Highlight Threshold

1. Go to the Colour > Grading menu.
2. Grade the image up and down. You want to exaggerate this grading to check whether there is either any clipping in the highlights or noise in the midtones (and shadows).
3. In the Image > Transcode menu, adjust Highlight Threshold.

Regarding the Grading of HDRx Footage

In the High Dynamic Range mode, Lustre imports HDRx footage as half-float (aka 16 fp). The same considerations apply as when reading OpenEXR files.

• Put in place an output LUT to tone-map the values (i.e. convert from HDR to video).
• Keep in mind that Lustre grades floating-point values by converting them to a logarithmic format. This allows the grading tools to work much as you are used to when grading log film scans. Control the scene-linear to log conversion using the Float Conversion LUT (Project Settings > Calibration).
• Try using the log_default as the Float Conversion LUT and the log_default_tonemap as your Render-->Output LUT as a starting point. This should provide a grading experience similar to grading log film scans through a print-film emulation LUT.

As with OpenEXR, RED HDRx images (in High Dynamic Range mode) come into Lustre with values above the normal grading range. For example, with 10-bit film scans 1023 comes in at the top of the normal grading range. If you turn your viewing LUT off the full grading range is mapped across the black-to-white on your projector, and you can see all the highlights detail on the negative. However, internally Lustre has a much larger working range and as with OpenEXR, HDRx images may start out with highlight detail that is outside the usual grading range. As such, even if you turn your tone-map off, you may still need to go into the Colour > Grading menu and grade down the image to see all of the highlight information available. So even though it may not be initially visible, keep in mind that there may be a vast amount of information in the Lustre working space that is available to grade via secondaries and al.

Red Flip metadata

When working with a Stereoscopic camera rig where the camera orientation has been modified to capture footage, it is possible to set the orientation of the image. Wiretap Gateway is able to read this data and automatically present the image in the right orientation. Note that any timeline created with media files with this metadata prior to Wiretap Gateway Server 2012 Extension 1will not show the media orientation based on this metadata. This may create different results than previous versions.

About RMD files generated by REDCINE-X

The latest version of REDCINE-X is able to generate RMD (Red Metadata) file with the HDRx Blend Exposure value. This data is not yet supported in Wiretap Gateway 2012 Extension 1.