Barry_Green
Moderator
You've seen it, you've read about it, you've heard it, but you may not understand it. What's with all the threads about "noise" on the 170, and how the 200A supposedly looks better? It's been enough of a beef among users that I took a few hours to try to get to the bottom of it.
I set up an HVX200A and an HPX170 to shoot res charts, color charts, grayscale charts, and a real-world "scene". I used Adobe OnLocation for all monitoring, for two specific reasons: first, nobody really cares what the "live" output looks like, as it's the recorded footage that matters. And second, comparing HD-SDI to component will automatically make the 170 look "noisier" (because the HD-SDI will show all the signal, whereas the analog component will potentially roll off some of the highest frequencies, and because each camera uses a different cable I can't guarantee that the component signal is going to be representatively equal).
So I used OnLocation, streaming 1080/30P footage out the firewire port in the exact format that it would be recorded in. I chose 1080/30P for the highest possible resolution and avoiding all potential interlace artifacts (such as would come from 1080/60i or the pulldown inherent in 24P/24PA).
I shot a 12-step grayscale chart to check luma noise at a wide variety of IRE levels.
I shot a color chart to look for induced chroma noise separate from luma noise.
I shot a resolution chart to compare the two after I figured out what was happening.
And I shot the CamBelles to have them represent a more realistic real-world shooting situation.
For those who don't want to be bored by all the rest, here's the long and the short, the fat and the skinny: the HPX170 delivers a better-looking picture than the HVX200A does. That's just the way it is, folks. Reports of noise and whatnot are misinformed based on not understanding the differences between the two cameras. Hopefully my testing will help elucidate those differences and show folks how to get even better-looking footage from their 170 than they could from a 200A!
So, okay, what's the firestorm about, and what's the real deal? The firestorm is that the 200A came out and looked really, really clean. EX1-class clean. Little to no noise. Yet the 170, under the same settings, looks a tad bit noisier. So we've had theories tossed around related to lens diameter, pre-amp gain, etc. In my opinion, those are all red herrings. The real secret is in the CORING control. The CORING has been changed between these two cameras, and unfortunately the settings aren't the same. Just like the Master Pedestal is different between them, so is the coring. Equalize the coring and you'll equalize the noise.
All tests were shot with all menu settings at F1 defaults, meaning zero across the board, HD NORM gamma, NORM matrix, etc. I changed the MP to deliver 0% on the MARKER with the lens cap on (that meant -2 on the HVX200A, and -5 on the HPX170). I also fiddled with the phase to try to get comparable color (more on that later).
In my testing, it seems like the coring in the 170 has been tweaked downward around two notches. What that basically means is, all other things being equal, the 200A at CORING 0 is about equivalent to an HPX170 at CORING +2. And that means an HPX170 at CORING 0 is about equivalent to an HVX200A at CORING -2. So you can't have both set at zero, or yes the HPX170 will look noisier. And, truthfully, I think with an HVX at 0 and an HPX170 at +2, the HPX170 looks less noisy, so maybe the true number should be +1.5, but since we can't set +1.5, I say go with +2.
BUT -- won't turning up the coring make the image softer? If we set the HPX170 to a larger coring value, won't that just make the image a little blurrier? Ho ho ho, hold on to your seatbelts folks, because this is where it gets really fun -- rather than being "noisier", the HPX170 has been tuned to be SHARPER than the HVX200A! I would put the change at about 40 to 50 lines of resolution higher than an HVX200A. Even after equalizing the coring, the HPX170 still shows more detail than the HVX200A does! I even shot the res chart with a +3 difference between the HVX to the HPX170, and they look basically exactly the same with the coring turned up that far!
So yes, I'm flat-out saying it: crank up the coring a little bit and the HPX170 will be NO noisier than the HVX200A, and in fact will be smoother, slightly LESS noisy, and still be sharper! Which means the footage looks BETTER. Slightly better than a 200A, and significantly better than a 200.
Here's the rest of the story: the HVX200A has a very slightly greener cast to the image under white balanced conditions than the HPX170 does. I used professional fluorescent daylight lighting, and manual white balance (and yes, black balance) on both cameras. Matching them for color was not as easy as I would have hoped. In the end, I went with -2 on the phase for the HPX170, which resulted in an extremely slightly purple bias upon deep examination in post; I probably should have stuck with zero on the phase. But on the HVX200A, there was enough green in the image that I went to +2 on the phase to try to match the HPX170 at -2! I probably went a hair too far on both, so maybe +2/0 or +1/-1 would have been a better match, but the point is there's more green in the 200A than the 170. And once I'd rotated the phase, I found the reds to be slightly out of whack so I had to go to -1 on the COLOR TEMP on the 200A to get it to be a closer match to the 170. Never did get it perfectly spot on, but it's pretty close.
And as close as it is, I still think the 170 picture looks better. Not even from a color perspective, not even from saturation or pedestal, I'm just talking straight up noise texture. When properly set, the 170 looks better.
I know there's been some controversy, but this is my summation after spending about 8 hours working with these two units: the HPX170 beats the HVX200A in picture quality. You get better/truer color rendition, a slightly sharper picture, and (when you set the coring properly) you get no more noise, and even a slightly smoother less-noisy image.
I also found negligible difference in sensitivity. There have been reports of them being up to a full stop different in sensitivity, but I can't see how; in my testing at full telephoto and full wide, there is maybe a 1% to 2% difference in sensitivity between them. They are, for all practical intents and purposes, equivalent.
Once I figure out how to post embedded video I'll follow up with some examples.
Okay, video examples. These are all way-magnified extractions, designed to really exaggerate any examples of noise. These videos show the full-frame image, and then zoom in to a small portion to really magnify the noise.
First, a gray chart. Use the FullScreen button to view this in as big and magnified as you possibly can, and this will show noise in the various tones of the image.
Next, a color chart. Unfortunately I kind of messed this one up a tad because they're both shot at coring 0; I don't have a +2 from the HPX170 for this example.
Next, two examples at different coring levels of the CamBelles.
Next, a resolution chart extraction showing that even at +0 vs. +2, the HPX170 is still resolving a bit more detail.
Finally, a resolution chart extraction that shows that even with a +3 differential, the 170 is resolving just as much as the 200A. This is 200A @ +4, vs. 170 @ +7.
UPDATED: There's been some question raised about whether under the other gamma curves, the 170 might look noisier than the 200A. So I equalized the pictures as best I could and shot under the gammas that seem to matter most to people, being HD NORM, CINE-V, CINE-D, and B. PRESS. So compare for yourselves. These are extreme blowups, taking a 400x300 patch and blowing it up to full screen. View these in full screen size to magnify the noise as much as you can to see how these two products compare.
In these examples, I'm trying to equalize out the coring by having the 200A at 0 and the 170 at +2.
For my viewing, the 170 is no noisier and is probably cleaner than the 200A across the board.
But, for those who think that I'm just jacking the coring up and changing the picture by doing so, we can set the coring to be the same. I believe that is actually not equivalent; it seems to me that the coring has been changed on the 170 to where you need to use more aggressive coring numbers to deliver comparable coring results, but even so, what happens if we set them both to zero? This:
Pretty much any which way you slice it, the 170 is not any noisier than the 200A.
I set up an HVX200A and an HPX170 to shoot res charts, color charts, grayscale charts, and a real-world "scene". I used Adobe OnLocation for all monitoring, for two specific reasons: first, nobody really cares what the "live" output looks like, as it's the recorded footage that matters. And second, comparing HD-SDI to component will automatically make the 170 look "noisier" (because the HD-SDI will show all the signal, whereas the analog component will potentially roll off some of the highest frequencies, and because each camera uses a different cable I can't guarantee that the component signal is going to be representatively equal).
So I used OnLocation, streaming 1080/30P footage out the firewire port in the exact format that it would be recorded in. I chose 1080/30P for the highest possible resolution and avoiding all potential interlace artifacts (such as would come from 1080/60i or the pulldown inherent in 24P/24PA).
I shot a 12-step grayscale chart to check luma noise at a wide variety of IRE levels.
I shot a color chart to look for induced chroma noise separate from luma noise.
I shot a resolution chart to compare the two after I figured out what was happening.
And I shot the CamBelles to have them represent a more realistic real-world shooting situation.
For those who don't want to be bored by all the rest, here's the long and the short, the fat and the skinny: the HPX170 delivers a better-looking picture than the HVX200A does. That's just the way it is, folks. Reports of noise and whatnot are misinformed based on not understanding the differences between the two cameras. Hopefully my testing will help elucidate those differences and show folks how to get even better-looking footage from their 170 than they could from a 200A!
So, okay, what's the firestorm about, and what's the real deal? The firestorm is that the 200A came out and looked really, really clean. EX1-class clean. Little to no noise. Yet the 170, under the same settings, looks a tad bit noisier. So we've had theories tossed around related to lens diameter, pre-amp gain, etc. In my opinion, those are all red herrings. The real secret is in the CORING control. The CORING has been changed between these two cameras, and unfortunately the settings aren't the same. Just like the Master Pedestal is different between them, so is the coring. Equalize the coring and you'll equalize the noise.
All tests were shot with all menu settings at F1 defaults, meaning zero across the board, HD NORM gamma, NORM matrix, etc. I changed the MP to deliver 0% on the MARKER with the lens cap on (that meant -2 on the HVX200A, and -5 on the HPX170). I also fiddled with the phase to try to get comparable color (more on that later).
In my testing, it seems like the coring in the 170 has been tweaked downward around two notches. What that basically means is, all other things being equal, the 200A at CORING 0 is about equivalent to an HPX170 at CORING +2. And that means an HPX170 at CORING 0 is about equivalent to an HVX200A at CORING -2. So you can't have both set at zero, or yes the HPX170 will look noisier. And, truthfully, I think with an HVX at 0 and an HPX170 at +2, the HPX170 looks less noisy, so maybe the true number should be +1.5, but since we can't set +1.5, I say go with +2.
BUT -- won't turning up the coring make the image softer? If we set the HPX170 to a larger coring value, won't that just make the image a little blurrier? Ho ho ho, hold on to your seatbelts folks, because this is where it gets really fun -- rather than being "noisier", the HPX170 has been tuned to be SHARPER than the HVX200A! I would put the change at about 40 to 50 lines of resolution higher than an HVX200A. Even after equalizing the coring, the HPX170 still shows more detail than the HVX200A does! I even shot the res chart with a +3 difference between the HVX to the HPX170, and they look basically exactly the same with the coring turned up that far!
So yes, I'm flat-out saying it: crank up the coring a little bit and the HPX170 will be NO noisier than the HVX200A, and in fact will be smoother, slightly LESS noisy, and still be sharper! Which means the footage looks BETTER. Slightly better than a 200A, and significantly better than a 200.
Here's the rest of the story: the HVX200A has a very slightly greener cast to the image under white balanced conditions than the HPX170 does. I used professional fluorescent daylight lighting, and manual white balance (and yes, black balance) on both cameras. Matching them for color was not as easy as I would have hoped. In the end, I went with -2 on the phase for the HPX170, which resulted in an extremely slightly purple bias upon deep examination in post; I probably should have stuck with zero on the phase. But on the HVX200A, there was enough green in the image that I went to +2 on the phase to try to match the HPX170 at -2! I probably went a hair too far on both, so maybe +2/0 or +1/-1 would have been a better match, but the point is there's more green in the 200A than the 170. And once I'd rotated the phase, I found the reds to be slightly out of whack so I had to go to -1 on the COLOR TEMP on the 200A to get it to be a closer match to the 170. Never did get it perfectly spot on, but it's pretty close.
And as close as it is, I still think the 170 picture looks better. Not even from a color perspective, not even from saturation or pedestal, I'm just talking straight up noise texture. When properly set, the 170 looks better.
I know there's been some controversy, but this is my summation after spending about 8 hours working with these two units: the HPX170 beats the HVX200A in picture quality. You get better/truer color rendition, a slightly sharper picture, and (when you set the coring properly) you get no more noise, and even a slightly smoother less-noisy image.
I also found negligible difference in sensitivity. There have been reports of them being up to a full stop different in sensitivity, but I can't see how; in my testing at full telephoto and full wide, there is maybe a 1% to 2% difference in sensitivity between them. They are, for all practical intents and purposes, equivalent.
Once I figure out how to post embedded video I'll follow up with some examples.
Okay, video examples. These are all way-magnified extractions, designed to really exaggerate any examples of noise. These videos show the full-frame image, and then zoom in to a small portion to really magnify the noise.
First, a gray chart. Use the FullScreen button to view this in as big and magnified as you possibly can, and this will show noise in the various tones of the image.
Next, a color chart. Unfortunately I kind of messed this one up a tad because they're both shot at coring 0; I don't have a +2 from the HPX170 for this example.
Next, two examples at different coring levels of the CamBelles.
Next, a resolution chart extraction showing that even at +0 vs. +2, the HPX170 is still resolving a bit more detail.
Finally, a resolution chart extraction that shows that even with a +3 differential, the 170 is resolving just as much as the 200A. This is 200A @ +4, vs. 170 @ +7.
UPDATED: There's been some question raised about whether under the other gamma curves, the 170 might look noisier than the 200A. So I equalized the pictures as best I could and shot under the gammas that seem to matter most to people, being HD NORM, CINE-V, CINE-D, and B. PRESS. So compare for yourselves. These are extreme blowups, taking a 400x300 patch and blowing it up to full screen. View these in full screen size to magnify the noise as much as you can to see how these two products compare.
In these examples, I'm trying to equalize out the coring by having the 200A at 0 and the 170 at +2.
For my viewing, the 170 is no noisier and is probably cleaner than the 200A across the board.
But, for those who think that I'm just jacking the coring up and changing the picture by doing so, we can set the coring to be the same. I believe that is actually not equivalent; it seems to me that the coring has been changed on the 170 to where you need to use more aggressive coring numbers to deliver comparable coring results, but even so, what happens if we set them both to zero? This:
Pretty much any which way you slice it, the 170 is not any noisier than the 200A.
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