Yeah, I had to grade commercials a couple of years ago, delivered as Log in 8 bits MpegII. Shot in a supermarket where there is funny light here and there. (To make meat look better.)
The normal fluor light has a very low CRI. It was hell. At a certain shot I had about 16 colors to draw a face. Amiga all over again.
https://www.youtube.com/watch?v=bT4fRsX8rvs (Not the worst one, but I fail to see the 'increased dynamic range', and trust me, I've tried. Used Resolve with tons of masks, there was nothing to save…)
On a lot of Log shots you see that there are no blacks and no whites, only about 1/3 or less of the dynamic range is used, and there is very little color.
Now, if you stretch that to full, you will suffer somewhere, even if you have 10 (theoretical) bits..
Next, to pull a good key you need a decent codec. Why not add a video assist recorder (BM, Atomos or my loved Sound Devices Pix) and shoot in Prores or DNxHD?
Just run tests, shoot color gradients or alike, grade and if you see banding you know for sure that it is a dead end.
On 20 Jul 2019, at 08:14, bigfish@pacbell.net [Avid-L2] <Avid-L2@yahoogroups.com> wrote:The bit depth on the mxf files from the Cannon Camera is 10 bit which I've been told on this list should be the bare minimum for shooting log as 8 bit can get crunchy. I'm no video purist I just get stuff to look the best I can make it and still make air.
---In Avid-L2@yahoogroups.com, <bouke@...> wrote :So when my Post Supervisor told the DP it was better to shoot Rec 709 for green screen the response was, "Why would I want to give you less information."The DP might have a point that he does not want to give you 50Mb 8 bits MpegII if he can also switch the cam to a better codec.But log still does not make sense. Raw does.Clearly the DP doesn't really understand the reality of what shooting Log actually does to the information.Virtually no-one does, and almost all log i've seen was way underexposed, trashing even more info.As has been pointed out in this thread shooting log sacrifices chroma info for luma info, if I understood that correctly.Yes, but not in all cases. IIRC, Arri once came out with 'some' form of log to compensate for omissions in their codec. sorta kinda Dolby for video.In my mind shooting log packs more latitude of exposure into the limited space of the codec and it also sacrifices information detail in bright areas to give more detail to the darker areas because the human eye is less sensitive to detail in the highlights.So in a nutshell there is only so many steps in 10 bit and shooting log compresses greater latitude into a smaller space that will then be decoded back out to the as much latitude as the deliverable specs allow. But putting more range into less range and then stretching it back out is adding quantizing issues etc…The amount of steps in 10 bits is 4 times more than in 8 bits, and 12 bits has 4 more steps than 10 bits.However, most of the time not all colors theoretically possible fit in the color space of the codec.But 10 bits to start with gives room if output is broadcast, that is (afaik) almost always 8 bits.Why is this such a misunderstood concept?The emperors clothes combined with the collective stupidity of this bizz to always do things the most complicated way without testing the entire workflow.Eg, people started shooting with DSLR's, we all got tons of out of focus video. People bought REDS while horsepower to de-bayer was not yet there. Nowadays it's the Canon XF705 that records in a format that needs tons of preprocessing before you can edit with it.Shooting log totally overcomplicates things. Back in the lineair days, grading was an extra, I've made hundreds of hours of television without it, and still the sun came up every morning.In the end, there is only one thing that counts, the end result.Now, for a very high contrast shot with no means to control the lighting Log has a place. (Again, if you know how to expose while shooting log, and have a good grader.)There is a new craft out there, called DIT. (Digital Intermediate Technician.) Someone who knows what buttons to push in the menu of the cams in what situation to achieve max quality.I myself have never been able to grade a shot to match the same one shot with the same cam not set to log, and definitely the log footage always looked worse. (Granted, I'm not the best grader out there.)To send files, go here:
__._,_.___
Posted by: Bouke <bouke@editb.nl>
| Reply via web post | • | Reply to sender | • | Reply to group | • | Start a New Topic | • | Messages in this topic (13) |
this is the Avid-L2
SPONSORED LINKS
.
__,_._,___
No comments:
Post a Comment