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Old September 6th, 2008, 02:08 PM   #1
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Highlights get washed out - the gamma curve?

Hi! I have big problem with the highlights, I always get washed out skies, lamps, windows (no details, just white) when I expose so the rest of the scene is alright. If you look at the example you see that the levels shows no cliping in highlight. In the dark parts (left side of the histogram) I have to adjust to really get it black (I move the left triangle .

http://www.access.se/redrockmicro/hi...example_01.jpg

I get this with or without the M2 adapter. I start thinking this is a gamma curve thing. Is it possible to adjust this in the camera so I get a wider spectra? What I really want to do is to adjust the curve so black really gets black and the white parts in the picture still shows details. Is it possible?

Regards / Jimmy
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Old September 6th, 2008, 07:00 PM   #2
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The level is clipped. 255 is maximum for 8bit, and your on it. The sensor is capable of far more dynamic range than the codec, so you need to compress the highlights of that range to suit. Fiddle with your Knee in the PP menu. Maybe try 80-90 Point and +20-25 Slope. If it desaturates too much, bump up the Knee SAT Level some. Fiddle till your in camera histogram no longer clips.
You could also try the old fashioned way, with graduated ND filters and so on.
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Old September 6th, 2008, 08:02 PM   #3
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Yes, the whites are clipped in that frame. You didn't say what PP you used; if STD gamma, the cines will roll off the highlights. In post I think the waveform monitor (luminance) is a better tool than the histogram; you would have seen the clipped region related to scene details. My general approach is to never overexpose any portion of the scene, but that isn't possible always. Try cine4.
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Old September 7th, 2008, 12:29 PM   #4
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Thanks for the imput! I will try to make some adjustments when I get to work tomorrow. One thing I was thinking about is that there IS a difference when using the cam "clean" and using it with my Redrock Micro Adapter. I do get more clipped whites WITH the adapter. I was reading the thread "Picture Profile Recipes" half the night and I found a lot of useful stuff. But I didn't find anything about PP's when using adapters. Maybe there is no difference, it just a exposure thing?

Thanks again. I get back as I have done some testing.

Regards / Jimmy
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Old September 7th, 2008, 12:49 PM   #5
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there IS a difference when using the cam "clean" and using it with my Redrock Micro Adapter.
Could be that Redrock's ground glass is blooming, thus the brightest whites appear washed out.
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Old September 7th, 2008, 01:38 PM   #6
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Yes, it could be. But ALOT of Redrock users use the Panasonic HVX200 and they don't come close to the white "blooming" on EX1. The ground glass should behave the same I think?

I have seen the white "blooming" even on Philip Blooms work, so maybe there's something the way EX1 treats light?

I hope that the input from this thread and the PP gallery can help things a little.

Regards / Jimmy
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Old September 7th, 2008, 01:42 PM   #7
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Just do what david said and set the knee, worked great for me.
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Old September 7th, 2008, 01:55 PM   #8
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And set exposure to keep the highlights from clipping, allowing the rest to be "underexposed" and then pull up the shadows and mids in post. Protect those highlights is video rule #1!
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Old September 7th, 2008, 07:17 PM   #9
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I use the Cine 4 setting, haven't done anything to the knee or anything else.

The zebras are set for 80 and 100 IRE. 80 gives me a sense that detail will be retained and 100 warns against clipping at the brightest highlights.

I'm able to get detail from the top of sunlit-cumulus clouds at noon, and still keep shadows under the bills of baseball caps.

I've even had people back-lit with sunlight glinting off the water behind them, and still saw faces. This camera is amazing. But just like any other camera, you have to avoid over exposure.

The histogram helps, too. Having the "mountain range" centered in the histogram frame helps reassure me that there will be a full range of tones.

I also use the eyepiece exclusively. The LCD is only used to access the menu items and never relied upon for exposure control or focusing.
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Old September 8th, 2008, 08:38 AM   #10
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[QUOTE=Dean Sensui;930621]I use the Cine 4 setting, haven't done anything to the knee or anything else.

Dean,

Do you also use Cine 4 for inside studio work, or shooting interiors? If not, what gamma setting do you use?

Thanks,

Forrest
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Old September 8th, 2008, 01:15 PM   #11
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Forrest...

I use Cine 4 for everything. It's like that rotisserie gadget marketed by Ronco: I set it and forget it.
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Old September 8th, 2008, 01:57 PM   #12
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Forrest...

I use Cine 4 for everything. It's like that rotisserie gadget marketed by Ronco: I set it and forget it.
Dean,

And, how do you have your picture profile set?

Thanks,

Forrest
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Old September 8th, 2008, 03:58 PM   #13
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Dean,

And, how do you have your picture profile set?

Thanks,

Forrest
Forrest...

I have two white balance presets. One at 5500k and the other at 3200k.

Then on both of them the detail and skin detail is turned "off".

The rest of the settings are default Cine 4 settings.
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Old September 8th, 2008, 04:48 PM   #14
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Forrest...

I have two white balance presets. One at 5500k and the other at 3200k.

Then on both of them the detail and skin detail is turned "off".

The rest of the settings are default Cine 4 settings.
So, outside of the Cine 4 settings, are you running with the camera default settings or something like Bill Ravens' TC2?
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Old September 8th, 2008, 05:00 PM   #15
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Just as a reality check here:
Cine 4 may work great for some people, but its hardly neccessary to get good exposure , and neither are Bill Raven's matrix settings neccessary though again people may find them lovely.

However, it is perfectly fine to use a normal gamma like Std 3, simply drop the black level to -6 (where it belongs to get black) and put the saturation level where you find it pleasing - probably raising it to hi sat. That's enough to get very good pictures with this camera. There is nothing wrong with those basic settings.

That's not to say you can't improve on it. I have changed those settings myself, but they really do produce very good pictures.

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