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Llaasseerr

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  1. Does that turn it into a full size HDMI port at the top? Yes, 48 would def be nice too.
  2. I'm quite into 72fps because it's a clean multiple of 24 and there are advantages to that, but 60 is obviously handy too.
  3. Just to put things in context, I measured ISO 3200 +1 stop with still a clean noise floor and clipping at a bit less than 20 in RGB, and Arri RAW clips at about 60. So pushing +3 stops with ISO 3200 could put it about 1/3 stop extra highlight detail over an Alexa, with the huge caveat of we would need to see how the shadow detail is holding in the raised noise floor. And obviously you could play this whole game of underexposing with an Alexa to a degree, but I'm just looking at a baseline.
  4. My quick finding from these clips is that at the same exposure, ISO 3200 is only marginally noisier than 800 so my prior thesis still kind of holds. I'm trying to clarify what the advantage of 3200 is, rather than the stream of conscious observation in my prior long post, So I think the simplest way to describe it with the limited dataset is: ISO 3200 = about the noise level between 800 and 1600, probably due to the change to the higher base ISO. But also, lower highlights capture. ISO 3200 +1 stop = same noise level as ISO 6400, but 1/4 stop more highlight capture. I'm just speculating for now, but if you were going to play the underexpose game then underexposing ISO 3200 by one stop more than underexposing 800 will give the best DR. I think. So maybe pushing it to the limit would be comparing underexposing 3200 by 5 stops vs underexposing 800 by 4 stops. Then back off from there one stop at a time if the black details are getting destroyed. I'm not including 1600 or 6400 because they don't seem relevant.
  5. I know this is getting off topic of the thread which is about the external recorders, but as far as using an SSD for internal DNG recording, if you use an NVMe stick and can get 1GB/s across USB-C then couldn't Sigma do a firmware upgrade where the camera could potentially output 6k RAW or HFR 4k 12-bit? It could potentially do 72fps.
  6. For sure, shooting 3200 with that much ND seems like a really interesting possibility if the black levels hold up! Thanks for re-uploading.
  7. Yes that makes sense, it would just be looking at the metadata tags in the ProRes RAW file that say it's V-log and applying the linear to log transform for display. But as you say since it's not baked in, you can easily change the transform to another log curve/gamut available from the drop-down list. I guess Atomos just decided that for generic cameras they will set it to V-log. It's not meant to make any difference what log curve and gamut you use as intermediate encoding if you have a colour managed pipeline. For example in ACES if you use the V-log IDT for V-log or the Alexa IDT for LogC. But it's worth noting that V-log clips at 46 in linear space vs 55 in LogC. Probably not a problem for the Sigma fp though!
  8. I'm just noticing the shadow levels are getting a little lost at the bottom of the waveform for the pushed 3200 image, so despite the fact it looked visually the same to me when inspecting noise per channel, it evidently is throwing a bit of detail out in service of the highlights. It will be interesting to see how the deepest shadows hold up if the image is shot -2 stops or more underexposed. Also, sorry for the numerous typos in the above post.
  9. Here's the highlight clipping without/with highlight recovery based on the just the red channel: ISO 100: 1.0 / 2.09 ISO 200: 2.0 / 4.13 ISO 400: 4.0 / 8.25 ISO 800: 8.0 / 16.1 ISO 1600: 8.0 / 16.1 ISO 3200: 5.0 / 9.92 ISO 6400: 8.0 / 16.48 ISO 12800: 8.0 / 16.73 So the clipping point in the DNG is reached at ISO 800, but it's just due to amplifying the signal by +3 stops from base ISO 100. ISO 800 seems to be the starting point for the Ninja V implementation, which clips at ~9.34. This seems about right since I don't think it uses any kind of highlight recovery. When I balance ISOs 100-800 to the same exposure, they're the same clipping point because 800 hits the max highlight value form that point on. The noise floor actually looks the same to me as well. In this case, ISO 1600 and up are not adding anything in the highlights. ISO 3200 clips earlier than the rest, so ~9.9 vs 16.1, but the noise floor is about the same as ISO 800. If you think about it, there's a net gain here because the highlights are holding about 1/3 stop less than 6400 but the noise floor is -1 stop less. So it's the same as 800, which is really just ISO 100+3 stops). So to me, the way to take advantage of this is to underexpose 3200 by at least 1 stop so you're rating for at least 6400. The effect is that the noise floor is the same as 6400, but the highlights now clip a bit higher. This ISO difference is the same behaviour with the Ninja V at 3200. I'm uploading two waveforms: 1. ISO 3200+1 stop vs ISO 6400. = +1/4 stops more highlight detail. Max value 19.86 vs 16.48 in the red channel, noise floor the same. 2. ISO 3200+2 stops vs ISO 12800 = +1 1/4 stops more highlight detail. Max value 39.7 vs 16.48 in the red channel, noise floor the same. For reference, Alexa's sensor clips at 55 in linearized logC which is only half a stop more, so it seems that the shadow detail would hold up okay if the ISO rating was pushed further. I was going to upload a split screen of the shadow noise, but it honestly looks the same in each image when inspecting each channel individually so take my word for it. It would definitely be interesting in more test images showing the same ISO range at the same exposure level (adjusted with either lens or ND), and also protecting the highlights. It does seem like there's plenty of room to push shadow detail way down and still recover a decent image. EDIT: I just want to clarify that in the +2 stops waveform image (LHS), the highlights are not getting clipped but they're in the upper code values of the log range and can be pulled back.
  10. Thanks! I'm taking a look right now. It's helpful that the light clips and that the underside of the cabinet is still relatively in shadow at the highest ISO.
  11. I should add that with the Ninja V it would be possible to do a transform to a log-ish image with a LUT, but I'm not sure if the highlights would be preserved. And then an additional LUT would be required to transform to a Rec709 image. These two transforms can be collapsed into a single LUT at the expense of highlight values above 1. It's possible the entire range could be preserved by underexposing the image and using the LUT to lift the exposure. In summary, if there isn't a built-in way, there probably is a way of forcing the Ninja V or anything else to display a usable monitoring image with some hacks and workarounds.
  12. You are correct, ProRes raw is linear raw the same as DNG. It is no great mystery. In ACES or a similar linear gamma project, the linearity is maintained but the exposure is shifted to account for where middle grey is so that there are superbright values in floating point above 1.0. In editing software besides Resolve, the ProRes raw file needs to be interpreted as log but it should still set it to the correct exposure. And then as you say, you apply a film print LUT to Rec709 or similar. You are meant to display raw images in log because it shows the entire range, before adding the look LUT in either HDR or SDR space. This is the big problem with this camera - people who say it doesn't need log are forgetting about monitoring. There is always an intermediate transform of linear raw to a log format before applying the display LUT since LUTs only work in 0-1 space. I spoke to Atomos, and they could not even say what the colour space is of the Sigma fp when monitoring native on the Ninja V, but I suspect it's somewhat like the OFF profile. This goes back to Sigma not documenting this. So it might be a kind of Rec709 space, but it seems that it's more flat than that. I also asked if there was a way to transform the native image into a known log format and they said no. So I don't believe there's any value in writing down those IRE values, since they are only ever within the context of the gamma encoded space of the image display (even though the underlying image is linear) and no-one can say how the image is encoded. That is why I asked, can you check false colour on the camera itself? If as others have said, it takes the values directly from the sensor. That might also give you some clues as to how to set it on the Ninja V. You can also create your own false colour LUT for the Ninja V.
  13. I'm thinking of making this as simple as possible, just an ISO change. Just so that there's a bright enough source that will clip the sensor at all those ISO settings, and also that there's enough shadow detail to challenge the noise level a bit.
  14. If anyone can upload some 12-bit DNGs shot through the ISO range with shadows and something bright enough to clip the sensor, that would be great! I think the following: 100, 200, 400, 640 (if that's possible), 800, 1600, 3200, 6400, 12800. Bonus for a grey card, but not essential. @OleB both your lightbulb tests were great, but maybe what would be easiest for a DNG test is to replicate the second test with the exposure increase via the ISO change, and without the compensation of stopping down the lens. It then cuts out one more variable.
  15. Before I say anything else, I want to clarify that when I mentioned a blue tint in my last post I did not mean from the camera - just that there was blue light in the scene that made the colorchecker skew towards blue, which is fine. What I was referring to as metering for the "Atomos ISO rating" is that you said you metered based on ISO 200 instead of 1600, for example. Given the amount of overexposure, I suggest trying to meter for the Atomos ISO value. if you just forget about false colour, what works for me with other cameras is to just take a meter reading and adjust the exposure based on that (with ND or stop down lens). Then I check in linear space in Nuke and it should be at around 0.18 in each channel of RGB (depending on scene light tint). Without Nuke, what I suggest is encode the linear image to a known log curve where you know the code value or IRE for middle grey, then check the raw log image to see that it's a close match. So the log encoding would need to be documented, which for example some Blackmagic ones are not. It seems the false colour "north star" would be to establish if the recent v4 internal version works predictably, if that actually measures the scene radiance as captured by the sensor. The grey card should hit green on the false colour as a sanity check for you while shooting. Regarding false colour on the Atomos and in general, I'll admit I have not been tracking exactly what you've been doing as it sounded a bit complicated. This may just be my preferred workflow and others might not like it, but I generally ignore manually reading IRE values. If I was going to consider using the Atomos false colour at all, I would instead aim to know that the false colour display is designed specifically for the image that you're monitoring. But again, there are many variables here since we don't know what the encoding of the OFF image is that is being sent by the Sigma to the Atomos, although I speculate it's the middle range of the linear scene capture that is then transformed to Rec709. But then you mention you're monitoring in PQ, so I don't know if the false colour is accounting for that transform, either. It seems that there are several undefined variables at play due to the undefined transforms. You might also find it helpful to see how the Falsify plugin in Resolve interprets the image: https://xtremestuff.net/falsify-false-color-transform-released-for-davinci-resolve/ Without having the camera in front of me, I would guess that the OFF output displayed is Rec709, so maybe first take PQ out of the equation and see if it works for you. Also just a note that it seems to me that for a ProRes RAW recording from the Ninja V where the camera manufacturer does not have a defined log curve/gamut, that Atomos adds Vlog/V-gamut metadata tags. But I don't think it's monitoring in that space on the unit. I think it just means that by default, when you're in some software later that it will read those tags and transform the linear/native sensor gamut to Vlog/V-gamut. However I've been overriding this and exporting as Alexa LogC/AWG. Overall, it's pretty confusing.
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