Professional Technical Guide — N-Log Recording — En
Table of Contents N‑Log: A Primer.................................................................... 3 • Why Use N‑Log?................................................................................4 Filming N‑Log Footage....................................................... 6 • Using Camera Controls..................................................................10 • View Assist........................................................................................11 • Ensuring Consistent Exposure....
N‑Log: A Primer The term “N‑Log” is an amalgam of “N”, for “Nikon”, and “log”, short for “logarithmic function”. The logarithmic function in question is that used in digitizing light levels based on the density characteristics of negative film to render expo‑ sure differences much as humans perceive them. This is known as a “log curve”. The process of filming movies using a log curve is referred to as “logarithmic” or “log-format” recording.
l Why Use N‑Log? Shooting in N‑Log format preserves details in highlights and shadows and expands the range of effects available through color grading. Preserving Details in Highlights and Shadows N‑Log preserves highlights and shadows in high-contrast shots, such as those that mix indoor and outdoor lighting. Non– N‑Log Footage shot without N-Log shows loss of detail in highlights. N‑Log N-Log produces colors with less ap‑ parent contrast but more variation.
Improved Color Grading Third-party movie-editing software that supports color grading can be used to process the same footage in a va‑ riety of different ways, as is shown in the examples below.
Filming N‑Log Footage To record N‑Log footage, connect the camera to a digital recorder that supports 10-bit video. Use a Type C HDMI cable (available from third-party suppliers) and be sure the camera is off before connecting or disconnecting the cable. Choose cable with connector for external device To film N‑Log footage: 1 6 Select 10 bit for Output data depth. N‑Log footage can only be recorded at a bit depth of 10 bits. In the setup menu, select 10 bit for HDMI > Advanced > Output data depth.
2 Enable N‑Log recording. Return to HDMI > Ad‑ vanced in the setup menu and select On (cannot record to card) for N‑Log setting. Note that N-Log footage is recorded only to the external device, not to the camera memory card. 3 Configure the recorder for HDMI input. For details, see the documentation supplied with the device. 4 Start filming.
N‑Log Recording While N‑Log recording is in effect, Picture Controls cannot be used, ISO sensitivity cannot be set lower than ISO 800 or to values of from Hi 0.3 to Hi 2, Active D‑Lighting and high ISO noise reduction turn off automatically, and photographs will not be taken when the shutter-release button is pressed all the way down. The camera may also have trouble focusing; this is not a malfunction.
Filming N-Log Footage Frame Size/Frame Rate Note the following when choosing a frame size and frame rate for N‑Log recording: Frame size/frame rate 3840 × 2160 30p 3840 × 2160 25p 3840 × 2160 24p Notes • Icons and characters in the monitor display at low resolution, but this has no effect on the footage actually recorded. • The angle of view is reduced to about 90% (Z 6 only; on the Z 7, the angle of view is reduced only when the DX image area is selected). 1920 × 1080 120p N‑Log recording not available.
l Using Camera Controls If On is selected for HDMI > Ad‑ vanced > External recording control in the camera setup menu and the recorder sup‑ ports the Atomos Open Pro‑ tocol, you can start and stop recording using the camera movie-record button(for information on whether your re‑ corder supports the Atomos Open Protocol, contact the manufacturer). The camera displays A in movie live view and B during movie recording.
Filming N-Log Footage l View Assist Although it increases the range of tones recorded, at default settings N-Log reduces the ap‑ parent contrast between colors when the footage is viewed in the camera monitor. If desired, the display of colors in the camera monitor can be simplified to enhance contrast for ease of viewing by selecting On for HDMI > Advanced > View assist in the camera setup menu.
Filming N-Log Footage l Ensuring Consistent Exposure If your recorder features a waveform display, you can film an 18% gray color chart and adjust exposure for a video signal level (IRE) of 35%, equivalent to a 10-bit code value of around 372.
N‑Log Specifications N‑Log specifications are available from the following web‑ site: https://downloadcenter.nikonimglib.com/en/products/492/Z_7.
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