Exposure Tweaking - Levels or CC

[Chris Harding]

Hi Guys

I always read somewhat conflicting advice regarding the adjust of footage where the whites have maybe blown out a bit or where back lighting has caused issues .. Now and again I'm faced with slightly over exposured bridal gowns at weddings and I tend to favour using the Color Corrector Plugin rather than using the Levels Plug in. I was thinking that maybe I have never bothered to find out the correct procedure for each?

With the CC plugin I just use offset to get the blacks looking good and gain to get the hilights looking good and then tweak gamma for overall brightness... Is this wrong?? With levels I normally pop in the B&W plugin and then set levels to 100 and 7.5 but just using the output sliders ...wrong again???

Is there a right/wrong way to use both and which is best for exposure tweaks?

Chris

[Don Bloom]

Hey Chris, I never learned what they taught in school (cause I never went) but I use a combination of CC, Levels to correct exposure mishaps. I sometimes throw Curves in there as well. Just depends on how bad I screw up ;-)
IOW, I use what works and don't really care about the correct order of things or whether 1 thing is right and another isn't, all I care about is results and I know you feel the same so if what you're doing works, why change, Right?
I'm glad you like your 50s. I'm liking my 700 and with some new work I'm getting ready to do, it apprears that it was the right camera choice for me. I'll let you know more about what I'm starting to do within the next month, still got some kinks to work out but it's something I had never thought about before but now I think I'm glad the opportunity smacked me in the face.

[Chris Harding]

Hey Don

So there are at least two of us that do things "our" way... the correct method is supposed to be that you add a B&W plugin to the clip (temporary) and then set black levels to around 7.5 and white to 100. That seems to work for me but the Levels Plugin has "input" and "output" and I just adjust with output only so I wanted to know if that was the wrong way?? I get much the same with the CC and use offset to get my blacks looking good and then tweak gain so the whites don't blow out .... sometimes using Gamma only seems to work well. It was simply an overly bright day with fierce backlight on Saturday's wedding and I set the EA-50 EV to +1.75 based on the photographer who was quite willing to be a "bride" .. However he wasn't wearing a long white dress so when the bride did arrive I was a tiny bit over on highlights.

Done 4 weddings now on the Sony EA-50 and love the cameras ... better dynamic range too!! Hope your 700 lives up to expectations on the first for the season too... Mind you, it certainly won't be a 100 degree F day in Chicago yet as you guys are only just getting into Spring!!

Chris

[Mike Kujbida]

Chris, see if this technique helps.

Put 3 filters, "Invert" (at 100%), "Color Corrector", "Invert" (at 100%).
Lift up the gamma of the color corrector in the middle.
This darkens highlights first, in the logarithmic fashion, more like a "iris closing" way.
I grabbed this from a thread on the Sony Vegas forum called "Help with Over Exposure!" at
Sony Creative Software - Forums - Vegas Pro - Video Messages
It looks like the original images have been removed which is too bad as this technique worked extremely well.

[Chris Harding]

Thanks Mike

I have used that trick before BUT it was the opposite ... I had totally blown out backgrounds (lot's of backlight) but the bride and groom were severely underexposed so the dynamic range I had to try to correct was hug and putting the inverts either side made a massive difference and it became quite useable.

This was with my Pansonic HMC80's with tiny 1/4" chips and not a lot of dynamic range to begin with and was a few years back and yes, the invert/cc/invert did the trick on footage which was usable.

Saturday's footage is pretty darn good even untouched my new Sony's have a much better range and despite setting EV a bit high (it would have been magic at +1 stop not 1.75!!) It's purely the brides huge white dress with the sun directly on it that's slightly blown out ...in fact I can correct it very easily using just CC or using levels ... To give you an idea the waveform shows the blacks at around 5 and the white level is probably peaking at no more than 110 so very little correction is needed.

I was purely wondering whether levels is the correct way to go or using the CC is easier ...with CC if I lift offset just a fraction to keep the blacks correct and just tickle the gain..I don't even have to touch gamma so the blow out is not really "blown out" but simply a little bright!! It was simply a venue on the top of a hill with plenty of sky behind a very dark gazebo ..The bridal party stood out in the sun and the officiant in deep deep shade and it was an extremely bright and full sun day ... not the best of situations. It's tough to try and expose for a dark shady gazebo with bright sky coming thru the centre and then bright sky either side and when you get it as balanced as you can, the bride arrives in this snow white dress that reflects light like a mirror!!

The input is, as always, much appreciated and the double invert plugin has saved my bacon once already..does anyone know why the inverts are needed??? Just curious!!

Chris

[Gerald Webb]

FWIW,
Lately Ive been using the Sec CC a lot for little things like this. Once you get the hang of isolating whatever you want to play with, be it a Luma high (what you have here),
or a Mid ( like getting your blue skies to look like they do on the weather reports, nice and saturated)
a certain Hue..... whatever.
Just tick the box to show matte, and zero in on what you want.
Great tool.
Levels are great for highlight recovery as well, use the Inputs and Gamma to shape your waveform, then use the Outputs to bring it back to within legal levels.

[Chris Harding]

Hi Gerald

I have never used the input sliders to do any waveform shaping... what do you use it in conjunction with ?
The videoscopes??

Then again I'm lazy!! I just use the output sliders to set my levels to limits and that's it!! Is there a nice advantage to adjusting input sliders?? You obviously need to do that first as it will mess with output levels.

Chris

[Gerald Webb]

Hey Chris,
Ill tread lightly here, since I will prob get burned by someone more schooled than myself.
But this works for me.
For DVD anything below 16 on the scopes is black, and anything above 235 is white.
The advantage with using the input sliders is that you can control how much of the greys in your scene become black at 16, and how much the almost whites become white/clipped at 235.
In the grab below, not a great example but its what I have loaded ATM, it was a little overexposed, but with the levels I can put my lows and highs where I want them, and control how much of them roll off to be crushed and clipped on the high end if I choose.
Interestingly, I can brighten the mids and end up with a brighter looking image and still have corrected to the top and bottom end to more acceptable levels on the scopes.
But note it is still within legal levels.
This is really basic, someone more knowledgeable than I needs to go into greater detail for all the variables.

[Chris Harding]

Thanks Gerald!!

Ok I see where you are going and that makes sense too!! I was only looking at the waveform intead of all the scopes. I can see how you are using the 4 controls to limit to 16 and 235..On mine it was only the bride's dress really that needs a bit of attention. It was in full sun so it really glowed big time!!

The effort to upload screen caps is much appreciated..I'll give that side a whirl on my ceremony footage in the morning

Chris

[Juris Lielpeteris]

I am primarily using color curves to get more exposure to the dynamic range of the objects are not sufficiently homogeneous lit. Often additionaly I'm using Color Corrector, but Levels existence was completely forgotten.

[Edward Troxel]

If you're interested in looking at third party tools, you might check out ColorFast from NewBlue. Check out the NewBlue forum here where you'll see a three-part series on how it works.

[Duane Adam]

I'll second colorfast. I use its luminance and highlights controls in secondary correction to tame blown out whites. It works better than using color curves in my experience. I also use the shadow function quite a bit to restore darker areas without effecting overall balance. Currently my favorite color corrector and I use it more than davinci resolve or adobe speedgrade.

[Tom Roper]

I use the levels plugin on the track to establish the min-max levels for legal output between 16 and 235. Then I use the curves plugin on the event to obtain the desired gamma which will remain legal no matter how far I twist the curves.

[Adam Letch]

For what its worth, I shoot pretty flat, whenever I CC I white balance, then use Curves, then finish with a slight touch up on levels to make sure its legal. Gives me a richer more dynamic look without being oversaturated.

[Tom Roper]

If you did levels first, before the wb, cc, curves, it would already be legal and wysiwyg, whereas if you do levels at the end, you just changed the appearance of all the edits.