C100: Noise pattern on C100?

A

Andy Turner

Active member
I am seeing some vertical patterns in the noise on my camera. Narrow vertical lines running up and down the image. I tried to capture it here:


password: noise

It is hard to see on here...especially with vimeo's artifacts getting in the way (does it seem like this is getting worse to anyone else?...maybe just me) but I tried several lenses, ISO levels, aperture settings, this is in C-log but I tried other profiles as well. It shows up in the dark areas (obviously) for the most part, but I can see it in a lot of areas if I look. It is very pronounced when changing ISO and then settles down but remains there. Is this something with my sensor?
 
Yes I have noticed a vertical pattern in the noise, but usually only when the image is displayed at a much smaller scale in NLE viewer.
I didn't notice it when viewing full size though it's on my list of things to check out.
 
yea i've noticed that odd little changing iso settling in thing. when i first got the camera i left the body cap on and checked out all the ISOs.

but the thing about noise and the c100 is, if you underexpose, you'll likely get some ugliness, but if you expose proper, it'll look quite great.

It's a bit opposite from DSLRs, where you'd get away with the lowest ISO you can manage and boost it up in post, but the C100 benefits from the opposite mentality. use the iso as much as you need to get a proper exposure. for anything that i care about, up to 12,800 is great if needed, but if it's a choice between iso 20,000 or not getting the shot, it'll still look darned nice if that iso gets me proper exposure.

which ISOs have you been trying?

all of the closeup detail shots in this vid were at 12,800. and in some of the shots i post zoomed up to 200%, which i could never do with a dslr and have it not look like crap.

 
I had not heard of that mentality Darren. Is there an ISO range that you stay within? That just sounds foreign to my video background of keeping things at 0db and using gain only if you have to.

In the clip above I was moving between 320 and 20,000 for the end clip.

Here is a photo of an interview I shot the other day. It seems to be fine (shot at 850 ISO, Wide DR, 2.8) but if you tilt an LCD screen upwards you can see that the noise is in a whole bunch of very tiny lines. I know I am being picky here. I just want to know if my camera has an issue...if I just need to live with it, or if there are ways to avoid it?
interview test.jpg

EDIT: Of course I post this and I dont even see the lines in it :) I swear its there...aparently compression takes care of it though since I am having a hard time showing it to you!
 
imdjay said:
It's a bit opposite from DSLRs, where you'd get away with the lowest ISO you can manage and boost it up in post...
Click to expand...

No no no no no. Never do that. With any camera. I use the 5n, 7d, 5dmarkIII and NONE of them gets away with shooting low ISO and boosting post. Do it in camera.

Those lines are sensor artifacts in the shadows. Every camera has them at different levels but usually a black balance gets rid of them. 5dmarkIII is also quite noisy in the shadows but when you push those shadows down, you get rid of the lines. Or shoot with intermediate isos.
 
maarek said:
Those lines are sensor artifacts in the shadows. Every camera has them at different levels but usually a black balance gets rid of them. 5dmarkIII is also quite noisy in the shadows but when you push those shadows down, you get rid of the lines. Or shoot with intermediate isos.
Click to expand...

Please forgive my newbie questions: How do you set black balance on a C100 and what are the intermediate ISOs on the camera?
 
Hi Andy, it was one of the things I instantly recognized with my C100. Up to ISO 4000 it really looks very clean. Once I hit ISO 5000 the blue noise/vertical lines kick in hard and settle down. Then it's there upto 12,800 but bearable. Once I hit ISO 16000 and ISO 20000 it's all over the frame but light hides it. I guess it's normal. Doesn't look like C300 ISO 16000/20000 that I've seen.
 
maarek said:
No no no no no. Never do that. With any camera. I use the 5n, 7d, 5dmarkIII and NONE of them gets away with shooting low ISO and boosting post. Do it in camera.
Click to expand...


Your method suggests introducing additional noise with higher ISO in dslrs, let's take the 5d2 for example, if you need 6400asa of sensitivity to get exposure(extreme example), you're suggesting that you shoot 6400 which has seriously ugly line noise, vs shooting 3200 which has vastly less line noise, and boosting the highs in post?...

the c100 on the other hand has an entirely different architecture with different abilities, such as black balancing like you said.

you may have thought i was suggesting to severely underexpose to grab the lowest iso with dslrs, but i certainly wouldn't condone that, i should have specified that i was only referring to when in a situation where you're pushing the limits of the particular camera's signal to noise ration. such as what i described above. In my line of work it comes into play when shooting low key low light events where lights are just not an option, and i have to push the 5d as far as it can go. i've used 6400 on the rarest of occasions, and it just introduces far more line noise than a 3200 shot in the same light boosted in post.
 
imdjay said:
Your method suggests introducing additional noise with higher ISO in dslrs, let's take the 5d2 for example, if you need 6400asa of sensitivity to get exposure(extreme example), you're suggesting that you shoot 6400 which has seriously ugly line noise, vs shooting 3200 which has vastly less line noise, and boosting the highs in post?...

the c100 on the other hand has an entirely different architecture with different abilities, such as black balancing like you said.

you may have thought i was suggesting to severely underexpose to grab the lowest iso with dslrs, but i certainly wouldn't condone that, i should have specified that i was only referring to when in a situation where you're pushing the limits of the particular camera's signal to noise ration. such as what i described above. In my line of work it comes into play when shooting low key low light events where lights are just not an option, and i have to push the 5d as far as it can go. i've used 6400 on the rarest of occasions, and it just introduces far more line noise than a 3200 shot in the same light boosted in post.
Click to expand...

You just mentioned pretty much the ONLY time when that's the right approach on a DSLR (Canon's in particular at ISO 6400). Other than with the last generation Canon DSLRs at the very limit of their ISO ranges, the best method with pretty much every other camera in every other situation is to set your ISO as high as it needs to be for exposure. Underexposing by a stop will almost always result in a nastier image than bumping your ISO a stop.
 
to be fair, while i could have been more specific in the beginning, you did just agree to that specific situation after saying never ever ever to the general idea ;)

cheers to specifics on both ends. hugs and kisses all around.

back to the issue at hand.

OP, have you tried looking at the noise patterns with the body cap on? you can also shoot a chart, or simply some solid colors and see how the noise looks in each instance
 
imdjay said:
to be fair, while i could have been more specific in the beginning, you did just agree to that specific situation after saying never ever ever to the general idea ;)

cheers to specifics on both ends. hugs and kisses all around.

back to the issue at hand.

OP, have you tried looking at the noise patterns with the body cap on? you can also shoot a chart, or simply some solid colors and see how the noise looks in each instance
Click to expand...


Did a black balance and then did testing with the cap on. Still seeing the same thing. If this is normal I am ok...I just think it is odd.
 
Don't shoot ISO 6400 on the DSLRs, use ISO 5000. That lowers the blacks just enough to get rid of a lot of sensor noise. FS700 also has quite noisy blacks but it has dynamics to spare so you can usually just lower them down in post.

5d mark III looks still quite clean in ISO 5000.

But shooting 3200 and boosting it to 6400 is significantly worse than shooting 6400 and cleaning it up. With a DSLR. It's the shadows you need to worry about, not the midtones or highlights.
 
imdjay said:
well, you can download the original and compare yours to mine. i did this right after a BB:
Click to expand...

I downloaded yours and the noise is identical to mine. I had seen your test on vimeo previously but had not downloaded the original mts file. You have the same lines as I do. I feel confident now that there is nothing wrong with my camera and that the pattern will not be noticeable in real life situations. Thank for the help.
 
I have had my c100 for about a month now and have noticed the same vertical noise patterns as you have. It's been driving me a bit mad lately. I've gone to Canon Hollywood, EVS, Sammy's and Film Tools to compare and as opinions. Most don't have any experience with the c100 enough (including Canon Hollywood) to give me a definitive answer as to weather or not this is "normal" or not. The noise pattern is nicer and all but I'd like a cleaner image overall. I've ready some posts where c300 users complained about the same type of noise when that camera had just some out.

I've done several tests so far and will be doing more. Here are my thoughts. I first noticed this colored noise pattern possibly just like you Andy...shooting interiors around my house with regular practical lighting or ambient coming from the windows. Some shots were slightly under exposed. Walking into a nicely day lit room however didn't help much. I noticed a very noisy image throughout. Granted the noise pattern behaved differently in different lighting situations. In darker shots I'd see the very noticeable vertical noise pattern in the grays and blacks especially. In the brighter rooms I'd just see a more randomized noise pattern but with lots of the color jumping out of it. I'd see it in the shadows and skin tones especially. Stepping outside in bright daylight the noise is less noticeable but you can still see it in the darker areas.

All of this initial testing was done at ISO [850] & wide DR (cp8). I've recorded onboard to SD cards at 24mbit LPCM and into a Ninja 2 via HDMI to ProRes LT. I get the same results every time. Oddly (or not) the noise get's much much worse when you drop the ISO below [850]. This is where I start to see macro blocking and I start to see junk in the shadows and blacks similar to DSLR footage.

Since then I've shot a test tape for a reality show with it using the same settings. Noticed lots of noise in int/ext shots at various ISO's. I then did a lit table top test at various ISO's and CP settings. Put a black card and grey card in the background and had random foreground elements lit by one DIVA lite. Foreground elements seemed to be fine. A bit of noise in the shadows. The black card in the background was buzzing throughout, although not as bad as was in my first test in my house with ambient light.

At this point I'm trying to recreate this with other c100's and this is when I went to Canon, EVS and Film Tools. I get similar results to varying degrees. The inconsistency is nerve racking. Some shots I can barely notice it when properly exposed and having decent light but when I walk into a dark corner...just as bad as mine. I got this camera for the sensor...to help me have more flexibility in those challenging situations where I won't always have the proper light. If I can't even get a very clean image at the native ISO I can't expect much past that.

This issue is the only thing that bothers me really. Love everything else about it and from a practical and ergonomic standpoint it's a perfect camera really...but is this just the image that I should expect? I beginning to think this is it. With all the talk about how clean this sensor is, I really expected more.
 
maybe im just not sitting as close to my screen as you are, but feel free to point out vertical lines in any of these videos which are just about everything i've shot on the c100 so far, all with varying lighting conditions, color temps, etc...











 
darren,

most of your videos are locked down on a tripod. the noise pattern really becomes noticable when the camera pans over a dark area (hand held or on a tripod). point your camera at a black t-shirt and slowly move it back and forth - with my camera (and other cameras too, it seems) you can clearly see a pattern of vertical banding that stays stationary as the black fabric moves across the screen.

this only affects the shadows and anything above middle grey looks incredible. but that noise pattern is definitely there.

i actually returned my first c100 for an exchange as both me and my sales rep saw the issue and thought it was a defective camera. new camera does the same thing though... would love to know if others are still seeing this.

k

p.s. i have samples that clearly show the issue - if anyone wants to see them i'll upload them.
 
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