Transfer Values / Defect Ratings (Indication Level)
What way do most people here (or what is the proper way) to identify transfer value and defect ratings(indication level)?
If you check your transfer value between your cal block and the piece being inspected and the signal comes up lets say 4db above DAC when on the test piece. Is this considered +4 TV because its +4db over DAC or is it a -4 TV because you have to remove 4db to bring it to reference level?
The same question applies when rating defects. According to ASME you have to record anything that is greater than 50% DAC, so a defect thats at 50% DAC, is this considered a rating of -6 because its 6bd lower than DAC or is it +6 because you have to add 6db to bring the signal to reference level?