I would shout from the mountain tops that the LUT has no clothes. While in theory there are advantages to shooting in log in practice those almost always fall apart in my world.
I for one use the standard Arri LogC to Rec709 and the Panasonic Vlog to Rec 709 and Sony's various S3 and S2 gamuts as a good starting point most of the time.
I've heard it said that shooting log puts things into the sensors sweet spot, as been mentioned in this thread, but I don't understand that. My understanding is the intention is to sacrifice detail in the highlights to afford more detail in the low lights where it is more critical. Log is a math transform to compress too much contrast range into a smaller data range that the codec can handle. I don't see how any of this puts things in the sensors "sweet spot." The sensor is hit with whatever light comes through the lens and responds accordingly. The Log C or whatever transform is applied after this so it has nothing to do with a sensor sweet spot as far as my limited knowledge tells me. I'd welcome an explanation as to how the math transform has anything to do with the sensors sweet spot.
I do believe that the math transforms try to increase detail in the areas that the human is more sensitive to. Perhaps that is the sweet spot that people are referring to.
The bottom line when people shoot log on an 8 bit codec it can add more noise than it's worth. There are only some many steps of detail and if you look at the camera image un lutted you will generally see a contrast range of about 550 mV instead of the usual 700 mV in Rec 709. Fewer steps means less detail to me, please correct me here if I am wrong. I've also read that this is manipulating data so my waveform evaluation is perhaps not as valid as I might think. Again I'd love to understand this more.
One thing I know for sure is if you are shooting for Rec 709 delivery the cleanest path is to properly expose things for Rec 709 let the camera do the necessary contrast scaling to bring the image latitude in line with Rec 709 specs. Also when you shoot with WYSIWYG there is no longer the endless need for image manipulation just to see what they really intended in the field. There is a whole cottage industry built up around on set and pre processing the media so it is presentable. Much like the days of dailies in the film world. All that goes away if you shoot Rec 709 for a Rec 709 delivery.
Future proofing also gets tossed about and that is certainly a valid concern but again I find this a pointless argument for most of the projects I work on. If no one has re-purposed my 3D Swimsuit Spectacular from 1986 into 4K by now I highly doubt any of my current reality documentary/entertainment work will get upgraded in format in the future so shooting log is just unnecessary.
High end features etc... sure but most TV/Cable it's really overkill and a big time suck IMHO.
---In Avid-L2@yahoogroups.com, <bouke@...> wrote :
On 26 Jun 2017, at 23:52, RRF Avid rrfavid@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:Do I use the Source LUT as a starting point and then apply CC?Or just bring it in with no LUT, and use CC to make everything right?Depends. Generally we use LUTs to translate the color for creative editorial, review copies of dailies, etc. For grading, we strip our the LUTs and grade from scratch.- RichDoes Symphony CC provide access to the full range that Slog3 is intended to provide?Or just bring it in with no LUT, and use CC to make everything right?Do I use the Source LUT as a starting point and then apply CC?Since the productions boys got a Sony FS7, I've been trying to figure out the best way to use the files in MC/Symphony. They are very excited to give me XAVC-Slog3.If you have links for me to go read, please post them, but my main questions are about getting the video to look "right". I'm told that they can't do white balance anymore because that's disabled in the mode they shoot in. So when I have Source Settings using the default Sony LUT, so I'm having to make a white balance adjustment to everything anyway.
Posted by: bigfish@pacbell.net
| Reply via web post | • | Reply to sender | • | Reply to group | • | Start a New Topic | • | Messages in this topic (8) |
No comments:
Post a Comment