What is the difference between ... TVI, AVT and SCTV? ??

The concepts of AVT (Aim Values Tolerance), SCTV (Spot Color Tone Value), and TVI (Tone Value Increase) are all related to color management in printing, but they focus on different aspects. Let's see how they correlate:

1. TVI (Tone Value Increase):TVI is about the increase in the darkness of a printed color compared to its intended darkness in the design. It occurs due to ink spreading and absorbing into the paper, making the printed color appear darker.TVI is important for controlling the reproduction of tones, especially mid-tones and shadows, in offset printing.
2. AVT (Aim Values Tolerance):AVT deals with how much variation from the intended color is acceptable in the final print. It's about the allowable deviation in color reproduction.While TVI focuses on the darkness of tones, AVT is more about the overall color accuracy.
3. SCTV (Spot Color Tone Value):SCTV is a method to adjust how spot colors (specific, pre-mixed inks) are perceived under different lightness level. It ensures that colors look consistent, irrespective of their lightness or darkness.SCTV can influence how tone values (including those affected by TVI) are perceived in the final print.

In summary, TVI is directly concerned with how the tone values (darkness) of colors change in the printing process. AVT relates to the acceptable range of these changes (or any color variation), and SCTV adjusts the perception of these changes, especially for spot colors. All three work together to ensure accurate and consistent color reproduction in offset printing.