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    #31
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    If this is normal sensor behavior for the C500.2, it seems anyone with a C500.2 should be able to easily replicate the issue (e.g. underexpose by x, then push in post to reveal).


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    #32
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    This is what I have, shot the morning after I received the camera. Chasing my cats into some dim light. Not sure the ISO. Was shot Xf-AVC. I caution anyone about suggesting that this is somehow proof that this camera is defective. What you're looking at is the absolute noise floor of the camera, and if you think there should be clean detail there, then you simply haven't been paying attention (feel free to read Canon's white papers about log gammas, mat porwolls comments etc). But someone will, and if you do, I'll call you an idiot now, to save myself a post. (whew...glad I got that out).

    Here are two images...one is the native exposure...the other has been gained. The area I'd look at is the horizontal painted wood at the middle of the Frame to the right of Moki and Lila. (the area below is wood slats and so any horizontal pattern is that). Is there some patterning in the area I mentioned?....well...yeah...maybe. Is that normal for a canon, and many other cameras?...Absolutely. Actually, I'd say it's damn good for a Canon Camera. Edit: For perspective I added a version with the LUT applied. that's how dark the image 'should' look.

    While I'm at it, let me show you another shot, already adjusted. This one, originally nearly as dark as the first shot, I'd suggest tells us how much work canon has done on CMOS smear...the C300 mark II would have a nice fat streak across the leg of the bed...

    If I had to guess, I'll bet Airwolf's camera is exactly the same as mine. But that would be guessing. I'm not sitting there dealing with his camera, so I really don't know. But to me I think he's just underexposing, and thats that. Both he and the other poster both started out by taking about how they pushed the images "beyond what you'd reasonably do", showed us verifiably underexposed images, and then all of a sudden it's a defective camera.

    This will be the 3rd camera I've owned in the $16k Cinema EOS range. It's by far the cleanest.

    Noise floor.jpgNoise floor raised.jpgScreen Shot 2020-01-21 at 11.10.55 AM copy.jpgsmear test.jpg
    Last edited by Barry G; 01-21-2020 at 12:14 PM.


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    #33
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    Barry if you can closely replicate the other 2 cams, that would make a case that it's normal for the sensor. The examples you've posted so far look pretty good (and unlike the other 2 cams in terms of obvious streaks).
    I occasionally observed sensor smear on the C300.2, however is was very minor. Worse was the double image from NR (which Canon later (mostly fixed) with IIRC a -1 option for NR lol). Apparently I'm the only one who noticed aliasing on the C300.2 (shot a lot of talking heads with the 24-70 F2.8 II (fairly sharp lens)): that was super annoying (plus the soft 4K). The C500.2 appears to have aliasing controlled (oversampling) and real 4K now (oversampling), so indeed good progress has been made. That doesn't rule out manufacturing and QC issues (like the memory reader (not really Canon's fault directly)).


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    #34
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    I only pushed the image that far because after applying the stock canon LUT (which is supposed to be the fool proof way of grading Clog), I'm looking at the image and i'm going "what the hell is that streak?" Because I can see it in the shadows. I show it to my colleagues and they also see it. So I push it up and there is that ghost of a streak I was seeing, now in living color.

    After further testing, it's possible this is appearing most prominently when there is an over exposed object next to an under exposed object. That window for example, or a street light. But I can't reproduce that 100% of the time either.

    If that's the case and this camera just produces banding, what does that say about the camera, I can't shoot any over exposed objects and something dark at the same time? That's part of the reason I got a camera with "15+ stops of dynamic range". So it could outdo my Sony FS5, which by the way has never under even the worst underexposed circumstances ever produced a horizontal streak across the image. Noise yes, and lots of it, but never a defined shape like that. I've also shot quite a bit with the Blackmagic URSA Mini, and while that has a ton of fixed pattern noise when you raise the exposure up, it does not have this kind of banding, and I've pushed that camera to the extreme in a lot of uncontrolled situations, just shooting regular prores.

    Does this also mean that I always have to crush the blacks down? What if I want to see whats in the shadows? Sure one can argue that a more contrasty image looks better, cleaner, etc, but what if I don't want that for a particular shot?

    If this was a $1,400 EOS R, sure, i'll take banding in the shadows and say I underexposed it. For $16k I expect better. For that reason I sincerely hope this is just a defective batch of cameras.


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    #35
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    Quote Originally Posted by Airwolf View Post
    applying the stock canon LUT [...] is supposed to be the fool proof way of grading Clog
    Since when?


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    #36
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    I always thought that C500 MKII would be perfect for making cat videos.

    (I kid, I kid)


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    #37
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    Airwolf- in the hopefully unlikely event this behavior is considered normal by the manufacturer, especially if others can't replicate, you can first file a dispute with your CC (if you used a CC), otherwise this can be effective: https://www.dca.ca.gov/acp/songbev.shtml (there are similar laws in most states).

    Did you try black balancing?


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    #38
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    Quote Originally Posted by jcs View Post
    Airwolf- in the hopefully unlikely event this behavior is considered normal by the manufacturer, especially if others can't replicate, you can first file a dispute with your CC (if you used a CC), otherwise this can be effective: https://www.dca.ca.gov/acp/songbev.shtml (there are similar laws in most states).

    Did you try black balancing?
    Yeah, i'm using regular channels and giving them the opportunity to fix it before I go that far.
    I did ABB, in fact I did a test before and after ABB, and there was no noticeable difference.


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    #39
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    Quote Originally Posted by Airwolf View Post
    I only pushed the image that far because after applying the stock canon LUT (which is supposed to be the fool proof way of grading Clog), I'm looking at the image and i'm going "what the hell is that streak?" Because I can see it in the shadows. I show it to my colleagues and they also see it. So I push it up and there is that ghost of a streak I was seeing, now in living color.

    After further testing, it's possible this is appearing most prominently when there is an over exposed object next to an under exposed object. That window for example, or a street light. But I can't reproduce that 100% of the time either.

    If that's the case and this camera just produces banding, what does that say about the camera, I can't shoot any over exposed objects and something dark at the same time? That's part of the reason I got a camera with "15+ stops of dynamic range". So it could outdo my Sony FS5, which by the way has never under even the worst underexposed circumstances ever produced a horizontal streak across the image. Noise yes, and lots of it, but never a defined shape like that. I've also shot quite a bit with the Blackmagic URSA Mini, and while that has a ton of fixed pattern noise when you raise the exposure up, it does not have this kind of banding, and I've pushed that camera to the extreme in a lot of uncontrolled situations, just shooting regular prores.

    Does this also mean that I always have to crush the blacks down? What if I want to see whats in the shadows? Sure one can argue that a more contrasty image looks better, cleaner, etc, but what if I don't want that for a particular shot?

    If this was a $1,400 EOS R, sure, i'll take banding in the shadows and say I underexposed it. For $16k I expect better. For that reason I sincerely hope this is just a defective batch of cameras.
    If I were you, I would be expecting to be told that this is normal behavior for the C500 II. Some of the reviews have said they haven't noticed CMOS smear, but that was probably just in comparison to the C300 II. On the C300 II, the streaking would be so much worse and you wouldn't need to raise the blacks to see it. It would just look like you were wearing striped shirt even with a LUT applied.


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    #40
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    Hi Airwolf, I eliminated the classic quote so I could respond to each part...(my answers in italic)

    I only pushed the image that far because after applying the stock canon LUT (which is supposed to be the fool proof way of grading Clog), I'm looking at the image and i'm going "what the hell is that streak?" Because I can see it in the shadows. I show it to my colleagues and they also see it. So I push it up and there is that ghost of a streak I was seeing, now in living color.

    -------I applied the stock canon LUT to your image, and there is no streak visible, because the area in question is rendered completely black.

    After further testing, it's possible this is appearing most prominently when there is an over exposed object next to an under exposed object. That window for example, or a street light. But I can't reproduce that 100% of the time either.

    ---------This could be cmos smear as mentioned previously, and also minor veiling flare - not normally visible with normal processing, but when raising shadows, it can appear in a variety of ways depending on the source of the flare.

    If that's the case and this camera just produces banding, what does that say about the camera, I can't shoot any over exposed objects and something dark at the same time? That's part of the reason I got a camera with "15+ stops of dynamic range".

    ---------I've recommended that you consult Canon's white papers about their log gammas, HDR, etc. They are very blunt about the challenges achieving this kind of DR from their sensors. And the issues specifically with shadow noise. They are illuminating reads.

    So it could outdo my Sony FS5, which by the way has never under even the worst underexposed circumstances ever produced a horizontal streak across the image. Noise yes, and lots of it, but never a defined shape like that. I've also shot quite a bit with the Blackmagic URSA Mini, and while that has a ton of fixed pattern noise when you raise the exposure up, it does not have this kind of banding, and I've pushed that camera to the extreme in a lot of uncontrolled situations, just shooting regular prores.

    -----Fix pattern noise is generally not something that can be cleaned up in post. Take a look at the Fs7 xyla chart below and you'll see some streaking and plenty of fixed noise, and mountains of color noise around where the red line ends. Sony rated that camera at 14.7 stops, the reviewer about 12. (I'd have said more like 10 or 11 given the color noise.) There is a point in all of these cameras where the DR continues, but you can't really consider it usable, thus the term "usable Dynamic Range". Yes the C500 mark II has 15+ stops of DR. Is it all usable? No! Most cameras, including the ones you've mention are rated for around 15 stops. Most reviewers will tell you that they fall well short of that in terms of Usable stops. the only camera I know of that has typically rated it's DR accurately is that damn Alexa. 14 stops. 14 usable stops (well, maybe 13).

    Does this also mean that I always have to crush the blacks down? What if I want to see whats in the shadows? Sure one can argue that a more contrasty image looks better, cleaner, etc, but what if I don't want that for a particular shot?

    ---------No you don't. (not any more than you do with all those camera's you've used with their tons of fixed pattern noise.) You just have to expose properly. I've demonstrated that for you already. I expose properly, and wallah...no noise, no crushed shadows, no problems. Smarter people than me will tell you to never underexpose Log gammas. If you refuse to believe it, I don't know what to tell you.

    _______________________________

    Unfortunately this discussion we're having isn't a new one. People buy a camera with these specs, and log gamma and they think they are a get out of jail free card. That they don't need to pay attention to their exposure, that they can just "fix it in post". If anything these cameras take more discipline because they have that ability to get you into trouble. There is so much range visible in the viewfinder, it's hard to tell what's what. Now, If you took your beloved FS5 out of LOG mode and displayed strait Rec 709, and underexposed the image, you'd know it...the important stuff would be black..and so, you'd probably increase exposure. But then your highlights would be blown out. So then you'd have to go to work... you might have to get out a light, or a fill card, or a flag. Perish the thought!

    Log gammas are, for the most part, the same goddamn information as that rec.709 image, just spread out so you can push it around in post a little more. Thinking about it any other way is at your own peril.

    sony alexa xyla.jpg
    Last edited by Barry G; 01-21-2020 at 03:51 PM.


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