# C-LOG Canon 5D Mark IV - Insane noise level! Clip



## Rob77 (Aug 14, 2018)

The noise level when using C-Log on 5D mark iv is insane (in shadows, dark details)! Am I missing something here?
1080 - 1/50 - f1.4 - Started at ISO 200 in the clip

See a clip here





Zoomed in clip


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## bhf3737 (Aug 14, 2018)

LOG format helps you record maximum dynamic range, at the expense of some image tonality and detail, assuming that you are going to use noise reduction in post. For a low light scene like this, I would never shoot LOG because there is no extra extra dynamic range to record. LOG is meant for scenes that have 11+ stops DR. You should use log if the scene has enough DR and you really need that max DR. 
It is not a 5D IV problem. Any camera in this case will perform more or less the same. If you can record with more bit rate (e.g. 150mbps?), better color sampling (e.g. 4:2:2) and depth (e.g. 10 bit?) you may be able to get a cleaner look after noise reduction.


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## Rob77 (Aug 14, 2018)

bhf3737 said:


> LOG format helps you record maximum dynamic range, at the expense of some image tonality and detail, assuming that you are going to use noise reduction in post. For a low light scene like this, I would never shoot LOG because there is no extra extra dynamic range to record. LOG is meant for scenes that have 11+ stops DR. You should use log if the scene has enough DR and you really need that max DR.
> It is not a 5D IV problem. Any camera in this case will perform more or less the same. If you can record with more bit rate (e.g. 150mbps?), better color sampling (e.g. 4:2:2) and depth (e.g. 10 bit?) you may be able to get a cleaner look after noise reduction.


Yes! These conditions were extreme but it also happened when i filmed in well lit room. There was noise on a black t-shirt (see attached pic). 
I really need Log because the clips are going to be graded to match other material already shot


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## bgoyette (Aug 14, 2018)

To add to what's been said here. Log gamma's are NOT for digging details out of the shadows. What they give you is the ability to control in post, how the overall exposure is placed within rec 709, and generally function best when over exposed in brighter contrasted situations. Take this into a situation where you have adequate light. Expose to the right, (make the image bright) being careful to not clip your highlights, then in post you'll want to drag the the image down...crushing the shadows a little. All that noise should disappear. There is no free lunch with C-log...but if you learn how to use it, it can give you a more flexible image in post. (post script: The 8 bit c-log on the 5dIV is going to be a generally challenged beast at best...it will work...but it's not like a proper 10 or 12bit log on a real video camera....)


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## bgoyette (Aug 14, 2018)

Your definition of "well lit" is perhaps a bit imprecise...shooting an "un lit" black shirt against a sunlit window is a challenging situation...Again...you're trying to dig details out of the murk, and any log gamma will fail at this...now C-log on the 5dIV isn't going to have the 13-15 stops of some other cameras....so you have to see the scene for what it is and not try to shoot beyond what your camera is capable of...Here is a quick grade of that image...how it "should" grade in rec 709...a black shirt in the shadows...should be...uh...black. (and the grain disappears). But notice there is lots of additional detail out that window.....if you don't need all that exterior detail...then increase exposure, so the shirt will be "out of the murk" and you'll have a better result.


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## Rob77 (Aug 15, 2018)

bgoyette said:


> Your definition of "well lit" is perhaps a bit imprecise...shooting an "un lit" black shirt against a sunlit window is a challenging situation...Again...you're trying to dig details out of the murk, and any log gamma will fail at this...now C-log on the 5dIV isn't going to have the 13-15 stops of some other cameras....so you have to see the scene for what it is and not try to shoot beyond what your camera is capable of...Here is a quick grade of that image...how it "should" grade in rec 709...a black shirt in the shadows...should be...uh...black. (and the grain disappears). But notice there is lots of additional detail out that window.....if you don't need all that exterior detail...then increase exposure, so the shirt will be "out of the murk" and you'll have a better result.
> View attachment 179696


Thanks for the answers. Haha yeah not well lit in that way. But still it felt like a decent exposure when it comes to the skin. These were the settings (attached)


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## bgoyette (Aug 15, 2018)

It's pretty common for new users to Log Gammas thing that it means they no longer have to light anything...because "all that dynamic range", and try to "treat" Log like RAW. While C-log does give the user a RAW like experience (the ability to shift exposure in post), it's still a highly compressed 8 bit codec, and the limitations are obvious...noise in the shadows is a very common "new user bug" when shooting LOG. Here's another grade of your image...this one is probably closer to what you'd want it to look like. Notice now I've pushed the highlights up so the walls are reading white, and that's pushed most of the detail out of the window..the shirt and skin look better, but super graining still...this shows you what you should be doing with your exposure...if you want the walls to be white, and don't care about what's out the window...add 1-2 stops of exposure and your shadows will start to fall into line...or add some light to the subject. Good luck. You're well on your way to a real video camera


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## Rob77 (Aug 15, 2018)

bgoyette said:


> It's pretty common for new users to Log Gammas thing that it means they no longer have to light anything...because "all that dynamic range", and try to "treat" Log like RAW. While C-log does give the user a RAW like experience (the ability to shift exposure in post), it's still a highly compressed 8 bit codec, and the limitations are obvious...noise in the shadows is a very common "new user bug" when shooting LOG. Here's another grade of your image...this one is probably closer to what you'd want it to look like. Notice now I've pushed the highlights up so the walls are reading white, and that's pushed most of the detail out of the window..the shirt and skin look better, but super graining still...this shows you what you should be doing with your exposure...if you want the walls to be white, and don't care about what's out the window...add 1-2 stops of exposure and your shadows will start to fall into line...or add some light to the subject. Good luck. You're well on your way to a real video camera


Thanks!


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