why does my waveform say my blacks are below 0 IRE after I change the levels??/

[Tyler Smith]

i thought the green line on the right side of the waveform was represented peaks of blacks and whites….i was using this to balance the black and white peaks.

am i balancing my levels completely wrong? Should i also be stretching the blacks and whites as close to the 0 and 100 IRE level as closely as possible?

t

[Jeff Brown]

[tyler smith] “i thought the green line on the right side of the waveform was represented peaks of blacks and whites”

Hoo boy, do i feel stoopid. You’re right. I’m used to hardware ‘scopes; so I made a wrong assumption. But in the image of your overall waveform, I don’t really see anything below zero. Obviously, Premiere sees something there, and I’m not sure what.

[tyler smith] “Should i also be stretching the blacks and whites as close to the 0 and 100 IRE level as closely as possible?”

In my opinion –and take it for what it’s worth– see above ;>), you should not be stretching the levels “blindly”. Scopes are good to make sure the technical aspects of the video are correct, but for visual decisions, you really need a calibrated monitor to judge the image. Use ‘scopes to check your decisions, but trust your eyes too.

-jeff

[Tyler Smith]

Thanks for all the help Jeff…I played around a bit with it and you’re absolutely right. I set the whites and blacks as close to 0 and 100 as possible, that is if those levels are relatively close to the 0 & 100 values. I’m careful not to over do it to a point that ruins the image quality. If stretching & tweaking the levels improves the overall quality while keeping the technical aspects in check, then it’s a bonus. After that I might tweak the gamma in order to match it better with the preceeding & following cut, this really makes the flow of images so smoother…but it seems that the image is easily distorted and gamma is almost better to be used sparingly.

I Think I have a pretty good grasp on things now, and now only need to learn about color grading. 🙂

thanks,

tyler