Joseph Owens
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COW Coins
16
DaVinci Coins
Forum Replies Created
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[Khashyar Darvich] “If I removed the 3 duplicate “freeze” frames from the middle of the pan and closed the gap, then it would create a jump cut,”
What you’re saying is that the camera dropped three frames and filled in the gap with the last frame it saw before resuming the pan. My first down and dirty fix is to put a motion map on the freeze frames to try to follow the pan. Next strategy would be to try to synthesize the three missing frames by morphing between the adjacent good frames. There are a few applications which offer some form of that.
Still a PITA.jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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Depending on what the actual environment/content looks like or is supposed to represent, many times the purpose of green screen is to convince the audience that what they are seeing is a single composition. So after you have roughed in your plates, either by linking an alpha channel or extracting a matte from the blue/green/whatever foreground and connecting that to the appropriate plate layer, then you are simply grading to achieve what we always do.
Its very similar to grading around a foreground character or object with a secondary or power window, except the elements come from different sources/shots. It gets trickier if you are compositing action footage in front of synthetic scenery. Film grain, electronic noise, lens DOF, all these factors contribute to the authenticity of the complete shot. Then there are other issues such as perspective changes, lighting direction, shadows… it becomes an iterative process sometimes, since all you are supposed to be responsible for is the general feel between the elements so that they seem to be appropriate for their settings, but if care has not been exercised in designing the effect elements in the first place, all you can hand to the next step is the best compromise.
So your actors were shot under flat studio lighting (daylight) with a different camera, (say a 5K EPIC) than the bg element, which is a middle of the night alleyway that has a single (and flashing) practical emergency light offscreen (by a run and gun, handheld H264)? That would be fun. Ka-ching!
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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[Dmitry Kitsov] “Make your own HD bar chart in resolve with power windows”
You can’t be serious.
I know people try to make their own charts with Photoshop and various other graphic programs, but let’s just say that conflicting color profiles and a general unawareness of what goes into making a bona fide reference test signal generator goes beyond what a lay person, or a general operations technician can achieve. Color bars, for example, as simple as they may appear, are the result of a matrixed luminance/chrominance data field, and if you wish to create something similar to an EIA/SMPTE color bar standard (and this whole argument is about creating a universal reference) you will have to re-create the work that was done by a team of engineers in the ’50s, who actually understood all the ramifications of what they were doing… in terms of gamma, black point, white point (peak and APL), luminance/chrominance matrix (not just adding R+G=Yellow, for example — you get the wrong Y’ result), and added to that the fact that RGB/Cy,Y,Mag are not equidistant in relative phase.
Underscoring this exercise in futility is the reality that even if you were to somehow fluke a perfect SMPTE color bar reference, it is only valid for composite (baseband NTSC/PAL) transmission, which we don’t do anymore. There is no way to use SMPTE color bars to set up the overall emissivity of the display (which affects everything else), so roughing in the hue, black point, and saturation using blue-only (especially with a do-it-yourself image) is like lobbing a baseball back over the stadium wall and hoping it will land exactly in the middle of home plate. The national lottery is a better bet.
I absolutely understand the desire to “do things right”. But in order to do things right, you actually have to “do things right”.
But this is not much worse than camera assistants photocopying framing charts to shoot lens tests.
“But what would be wrong with that?”jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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[Arno Beekman] ”
that doesn’t mean that that is the problem though. the bottleneck might be earlier in the chain…”Yes, that bitrate is simply for file transfer, and doesn’t take sampling and encoding into account. Hardware capture in ProRes is fairly straightforward since the bitrate is only about 10% of Uncompressed, and you are only creating one file. DPX capture, depending on the bit depth, requires more processing and disk access becomes even more critical since you are writing one file per frame, which can quickly overflow any caching, so then the capture chokes.
The usual minimum number I work with in 1080P is 185 MB/sec, but with an external 20-drive quad-lane fiber channel RAID that is capable of 1.2GB/sec sustained. Seems like overkill, but that’s still cutting it close to the minimum for 4K…. uncompressed flows.
Its just the math.
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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My thinking as well, the screen captures seem to resemble a decode failure similar to for example Single-Link / Dual-Link confusion.
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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I’m wondering what you are referring to as a “project”. Resolve communicates with edit applications via EDL, XML, and AAF. If you edit a sequence in one of the majors, you must export a description of your edit to Resolve in one of those forms, which rebuilds the sequence as best it can (there are some banned operations which will cause failure to import). In Resolve, the command File, Import should open a browse operation that is specifically looking for XML from Final Cut, and AAF from Media Composer or Symphony.
“Import project” is looking for another, possibly archived or externally generated Resolve project, not a Final Cut prj.
Change Parent Directory allows you to re-link to other source material within a succesfully launched project, in other words the media should be already linked in some way; it is not specifically a Reconnect Offline operation.
These operations do work, at least they have been for a couple of years. For other opinions, it would likely be worth searching for some FCPX-specific round trip workflow tutorials. I understand there are tons of them available.
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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[Dave LaRonde] “You can’t trust the QT viewer to report accurate resolutions.”
Yeah, often its just parroting the header in the file and ignoring what it actually is.
Only a few applications will really tell you what the media is — Apple COLOR (because it operates outside of ColorSync and Quicktime, SHAKE, and Resolve. None of them Apple originated applications.
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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[David Dean] ” I’ll ask it in a different way — is this something I should be expecting with future ProRes to H.264 conversions? “
On a MacBook Pro, yes, pretty much. The times will go up if you try to set a target bitrate that a broadcaster might insist on.
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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At first blush, this faintly resembles the “rubber”-cam that you sometimes get when stabilizing seriously whip-lashed footage. The bottom of the frame doesn’t match the top geometrically, because the “scan” is temporally displaced. Handheld to start with, you can try a Smoothcam, but I’m betting the bottom will never match the top, because the imaging device is continuously rotating and translating. Originating format is…..??? an H264 Long-GOP HDSLR???
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.
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For an experiment, would you consider sending it to Compressor?
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.