EX1 adjusting color

[Craig Seeman]

There is someone by the name of Bill Ravens who has done this too but I don’t know if he visits the COW.

[Craig Seeman]

I did find Bill Ravens results though. He did this in January 2008 elsewhere:
________

First blush inspection of the EX1 color balance showed weak green/cyan and a fairly narrow dynamic range. The histogram filled only about 3/4 of the x axis and tended to be on the underexposure side of things. Granted, I don’t have a 3 color histogram, so, this is really an approximation. My goal was to increase the dynamic range, improve the exposure without blowing the hi-lites and muddying the shadows. I, also, wanted to bring up the weak green/cyan.

EX1, HDRack, and a DSC Labs Camette chart v8.1. Here’s my procedure and results:
1-Light DCS chart with 600w quartz halogen lamp
2-white balance the EX1- result of the WB=2700k
3-zoom EX1 onto 5-step gray chart on camette and look at the WFM.
4-adjust aperture so white step shows 100IRE
5-adjust black and black gamma so black step shows 0IRE.
6-adjust knee and gamma so middle gray sits at 50%IRE and all grey steps are evenly spaced
7-Now the hard part-zoom out to show the color bars on Camette. Turn on Picture profile mode and set MATRIX to ON.
8-adjust global and local phase angles to put all the color bursts within the vectorscope targets

Here’s my results:
Matrix———————on
Select———————hisat
Level………………………….0
Phase…………………………+6
R-G…………………………..+75
R-B…………………………..0
G-R…………………………..-18
G-B…………………………..-23
B-R…………………………..-33
B-G…………………………..+11

Color Correction…………..off
White………………………..off
Detail………………………..on
Detail Level…………………0
Detail Freq………………….0
Skintone…………………….off

Knee…………………………on
Auto knee………………….on
Point………………………..90
Slope……………………….0
Knee SAT level……………50

Gamma Level……………..0
Select………………………STD3
Black……………………….-15
Black gamma……………..-9
Low key sat………………0

It would be great to have someone validate my results. I’ll redo more fine tuning as I go on. For the time being, my latitude is increased above the factory settings, my saturation is more lifelike. The histogram now displays a range from near 0 to 100%. Peaks are well distributed over the range without favoring lows or hi’s.

I’d be glad to post some frame grabs if a server was available.

Time to go test in the real world.
I hope this helps out.

I tried all the gamma presets. All the CINE presets really compress the dynamic range about 30-50% of the available range. I suppose you could boost the LEVEL, but, then, I think you’re manually putting the gamma back in the STD preset

[Craig Seeman]

He later revised it to:
_________

I’ve reworked my original profile based on some feedback and observations I received. It was suggested I use a CINE profile for gamma, reds have been dialed down, black level was raised, slightly. Overall, this is an improvement, I really like this profile, altho’ my test was quick. I’ve posted a framegrab, so the comparisons are here:

Matrix ……………on
Select…………….hisat
Level………………0
Phase……………..-5
R-G……………….75
R-B……………….0
G-R……………….-18
G-B……………….-32
B-R……………….-27
B-G……………….13

Gamma Level…………..-40
Gamma Select………….CINE1
Black……………………..-12
Black Gamma…………..0

Once again, please set your white balance before using. Let me have feedback on your use of the profile.

[Craig Seeman]

and then changed
____

Gamma Level………….. 0 (changed from -40)

You lose a little dynamic range, but, it takes less CCing in post. And selecting a CINE1, 3,or 4 setting, depending on how much black stretch you want/need.
I think part of the lesson, here, is that the color matrix settings are good for a truer color, however, the way Sony applies gamma curve settings is a learning process for me.
One thing about my old settings is that the auto iris tends to underexpose unless one manually adjusts the iris for 100% zebra. It seems to be equivalent to something less than 1/2 f/stop since adjusting the level in TLCS by +0.5 is too much. Light level effects things

[Bob Hayes]

Thanks

I should contact Bill for sure. His posts sort of got me thinking I was on the right path or at least the same path.

[Bill Ravens]

Amazing to me that this has gotten the exposure it has gotten. With a lot more experience under my belt witht his cam, this profile still works well. Keep in mind that settings like DETAIL and BLACK LEVEL don’t really effect the color balance like the MATRIX adjustment does. Tweaking BLACK LEVEL is really based on the scene being shot. If you lower the shadows to near pure black(RGB 16 or less) the scene lighting needs to be carefully controlled so the shadows aren’t crushed(like an indoor performance). If you’re shooting outside, raise the BLACK LEVELS back up to give yourself a little headroom, aka wiggleroom, for uncontrolled variations more than 11 stops.

On the subject of dynamic range, I use Cine1 for outside under direct sunlight, Cine 3 for outside with filtered light(cloudy day) and cine 4 for indoors. If you happen to prefer the Standard settings, I tend to avoid Std1, altogether and always turn off AUTOKNEE.

[Bob Hayes]

Bill

Just the man I was hoping to connect with. No one seems that interested in the color of these cameras as opposed to the Panasonic community which is obsessed with color. My current goal is to create a standard color look for the camera which looks great and is flexible. I also plan to create some specific looks down the line.

I am continuing to play with the camera. My newest setting is:

EX1 7/8/09

Name Bob Hayes – Bobnorm

MATRIX On

Select HiSat
Level -21
Phase 3
R-G 79
R-B 41
G-R 39
G-B 36
B-R 24
B-G 68

COLOR CORRECTION
Setting Off
WHITE On
Offset A 0
Offset B 0
PRESET WHITE 3200
DETAIL On
Level -40
Frequency 0
CRISPENING 15
GAMMA Level 0
Select Cine1
BLACK -3
BLACK GAMMA 0
LOW KEY SAT 0

I have included a Leader Capture to give you an idea of where I am at. I would like to get the green and cyan 15% stronger and the green phased to cyan more. I would be surprised if these numbers track from camera to camera.

[Bill Ravens]

Bob I tried to do the same thing a while back. The best I could do was by turning the Color Correction ON and boosting the Green. My attempts were mildly successful, not nearly as good as the first cut, tho’.
here’s those settings:
Level: ………………………..0
Phase:…………………… -29
R-G: ………………………+31
R-B: ………………………48
G-R:……………………….. -2
G-B: ……………………….-32
B-R: ……………………..-38
B-G:……………………. +4
Color Correction………… ON
Target Phase:…………….. 274
Target Width: …………….0
Level: ……………………91
Phase:………………… -18
Knee SAT ……………….50
Gamma Level: ……………0

[Bob Hayes]

LOL. Sort of my results. I do like the idea of using the color correction as a limited matrix. When I tried to adjust the green the cyan section got truncated and since I couldn’t really see a difference I felt it was better not to tie up the Color correction in my overall look. I usually keep the green and cyan color saturation down as opposed to the other colors.

[Rafael Amador]

Hi Bill,
Great to have you around.
I’ve been trying many PPs that I found in Internet (Phillips Bloom, Douglas, Bass Pigs,..)
I worked for a while with which I think was your first PP.
I found too the Blacks a bit to low and the Reds just a bit too strong.
However this was very easy to correct in Color.
I will try now with the modifications you have done.
Many times I don’t know how the footage will be used, so I need a PP that gives me a picture the most natural possible while using the most of the dynamic range that the camera allows.
Bob complains that haven’t been many discussions about PP’s in this forum. He is right. This thread is the best example: Only four people posting.
But to discuss properly about PPs, I think is necessary a deep technical knowledge that I believe that most of the cameramen (at least my self) we don’t have it. Hope nobody get angry with me for this what I say.
Cheers,
rafael

http://www.nagavideo.com