Panasonic AU-V23HS1G Guide
V-Log/V-Gamut
REFERENCE MANUAL
November 28, 2014
Revision history
Revision Date Explanation
Rev.1.0 November 28, 2014 First Edition
Table of Contents
1. Introduction
2. Curve Characteristics
3. V-Log Formula
4. Colorimetric Information
5. Appendix
V-Log/V-Gamut REFERENCE MANUAL
1
V-Log/V-Gamut REFERENCE MANUAL
1. Introduction
This document describes technical information on the log curve and gamut used in Panasonic’s
“Varicam” for utilization in recording and workflow composition.
V-Log has characteristics similar to a log curve of a scan from negative film and is highly compatible
with conventional firm workflow. Light information collected via a lens is converted to electronic
information by sensors. In other words, light information and electronic information have a proportional
relation. Log curve characteristics show the relationship between the linear domain video signal and
exposure measured in stops, and a change in each stop of exposure increases or decreases the signal by
almost the same amount.
2. Curve Characteristics
Fig. 2.1 shows the characteristics of V-Log. This graph is defined as the x axis being exposure and the
y axis being 10bit code values. Fig. 2.2 shows reflection and code assignment. Gray output code with
reflection of 18% is defined as 433, black output code with reflection of 0% as 128, and white output code
with reflection of 90% as 602. Varicam also supports 12bitV-Log output, and a value four times that of
10bit code is the output code with 12bit code.
Fig.2.1 V-Log characteristics
2
Loading...