JeremyDulac

Happy New Year!
Alexa has a distinctive red (when LogC is paired up with the intended display primaries). It is a deep magenta red, and twists moreso approaching extreme saturation. This can look stunning. Other cameras may opt for the default of twisting towards orange with increasing saturation because Cmos red clips to yellow, and the gamut clipping is more coherent. For example, the Alexa has an especially messy extreme red clipping at tungsten WB. With Gen 4, this extreme red behavior is simulated. Here is P4Ka v Alexa in extreme gamut, with EC709 (P4K at bottom):

Apart from desired hue twists, like Arri display gamut, hue twists when conforming color spaces via interpolation (in log etc) have generally been one of the main challenges in developing EC (to keep the true clean hue lines as they should twist). At many stages, I've coded the engine to preserve clean hue lines. Hue is perceptually salient in color, and has a privileged place in the engine today (whereas once upon a time, it was just 'one of three' in the engine)

When exporting to YT and Vimeo from Resolve, I've found h.265 to be optimal. There is a slight magenta shift when the video sites re-encode the footage, and I've found it to be slightly less with h.265 (the colors are slightly more accurate). The difference for h.265, to compensate during export, is a node with -3 Tint. H.265 is also a much smaller filesize, which is less heavy on the Vimeo upload quota, and there is no size penalty for higher resolution.
However, I've found the sweet spot for streaming video sites is 2560x1440 (or 2560 pixels wide). The load times are not much worse than 1080p, but the apparent visual quality is much better (because 1080p is very compressed for streaming on these sites). The load times for 4k are much higher, with less of a leap in visual quality. Also, the fluidity of playback for 2560 is smoother than compressed 4k for streaming.
Here are my Resolve settings (horizontal resolution to match aspect ratio):

It appears there is only the option to set Quality to Auto-Best, or to restrict the upper bitrate (unlike Premiere). I gather that they've looked at the needed bitrate for each quality ranking, and kept the works 'under the hood'

That lut is literally not in the same universe as the level of work Alex has done here. I doubt that person profiled each camera - it looks more like hue curve adjustments in Resolve.

That lut is literally not in the same universe as the level of work Alex has done here. I doubt that person profiled each camera - it looks more like hue curve adjustments in Resolve.

That lut is literally not in the same universe as the level of work Alex has done here. I doubt that person profiled each camera - it looks more like hue curve adjustments in Resolve.

That lut is literally not in the same universe as the level of work Alex has done here. I doubt that person profiled each camera - it looks more like hue curve adjustments in Resolve.

12 bit log is RAW enough for me. I thought I needed CNG RAW so I got the USRA mini pro v1 and it turned out I did a session with both CNG and BRAW the difference did not make a difference for the project.
Really, this decision is a win for Blackmagic who is already marginalizing RED.
That said: RED thanks for the cinema camera revolution!  Those were good days when RED was the good guy, on the side of the little guy and I went to bed at night dreaming of 3k for $3k. I miss rooting for RED.
Now I’m rooting  for Blackmagic. I feel like my future success depends on Blackmagic’s future success, which is just silly, but that’s how my mind sees it.  I like believing that there are companies who gets what I need and are trying to deliver it.
At this point, as far as I can tell, Blackmagic is the company who Is trying to best meet my needs as a wannabe filmmaker.  
There I said it:  Blackmagic is for all us upstart-no budget-wannabe-filmmakers and I am very thankful!

I am glad I went with Braw in the end. It seems like the best and most supported "independent" compressed raw format right now.
This is a great opportunity for BlackMagic to gain more market share on raw formats.

Ah gotcha.

I'm not really directing this at you but just to anyone in general who isn't aware or wants to learn more, and I'm probably being a 'stickler for accuracy' here but obviously a sensor/camera has no inherent highlight rolloff as the sensor is linear (as close as practically possible with calibration) so highlight rolloff is mostly down to the dynamic range of the sensor, how the image is exposed and how the colourist chooses to roll off the highlights. All typical CMOS sensors will have "hard clipping" though, being linear capture devices.
I only say this because I see a few people mention 'highlight rolloff' as part of a log curve or colour science or something when in that respect it is just a by-product of the log curve optimising the dynamic range of the sensor in the container its being stored in. It's still assumed the user will create their own highlight rolloff in grading (I'm speaking just of RAW and log captures, not "profiles" or looks applied in camera intended for display on Rec.709 devices).

ARRI for example have a lot of stops above where they recommend middle grey be exposed for - due partly to their very large pixels and the large dynamic range they have - and when a log curve is calculated for mapping that dynamic range from middle grey to 940 (video white in 10bit where they map sensor saturation to in their log curves) you get a very flat curve at the top as it maps that range. When you flatten contrast that much it also appears to desaturate. I've seen some mention they believe ARRI purposely desaturate their highlights, but if they did that in processing before creating RAW files or LogC ProRes clips you wouldn't be able to inverse it correctly into linear for ACES workflows etc because processing like that is non-linear. They possibly do something like that for their LogC to Rec709 LUTs etc but people seem to attribute it to their LogC/RAW files too.

For our cameras we map sensor saturation at our "native ISO" to 940 also, but for ISO curve's above we go into "super whites" to make better use of the bit depth available especially since we deal so much with SDI output (10bit) and ProRes 422HQ is common for our customers (10bit also). ARRI says ProRes 444 (12bit) is the minimum for LogC because they don't use the full range available. We may change that in the future but the caveat would also be you would need to use 12bit for best results.
In theory you could expose a 10 stop camera/sensor so that you place middle grey at the second bottom stop, giving you 8 stops to create a very gentle highlight rolloff. You would just have VERY little range for the shadows. ?

So long story short, the question I would suggest people ask is 'what is the dynamic range like compared to other cameras' as that will really tell you what kind of highlight roll off YOU (the user) can create for your preference with how you like to expose given the amount of shadow information you like to retain, tolerance for noise, etc.

EXACTLY! Well said.

I mean the guy is only one person, and funding the camera rental, while nice, still doesn't pay the bills - which is where the time thing comes in, and Alex clearly has made a decision on what to do first based on the P4k demand. While that may not fit your needs, the Gh5s is becoming the minority, and I just think it is distasteful to act like he should just focus on what you want, because he said it is on the roadmap a long while back. He made no promises, and I am sure he has every intention of getting to it.
I was simply throwing some sarcasm out there.

DUDE,  people only paid for the Gh5 lut not the S! I dont recall Alex having a preorder for the S version. There shouldn't be anything to complain about. 
  You used the word "entitled" in an earlier post. That's how the likes of you sound on this thread  - "Entitled" for "Good money"
It's beyond ridiculous. Like Jeremy said, Folks probably  don't understand what goes into this.
Let's Allow the genius to create, refine and continually develop the Luts in PEACE

Its a sure thing that the S will be supported as an update to all 5 users. I made the classic error of making estimates based on projections of future productivity. This is something I've seen so often, I'm surprised I fell into it myself (I was one of those scarred by the 3K Scarlet experience, circa '08-'11, still waiting). I think smaller, independent manufacturers can fall into the trap of being too enthusiastic and optimistic about their own speed and potential.
Something key to the picture is that the P4K, by virtue of its gamut and range, revealed limitations that I had missed with the GH5. It has been crucial in determining what the process to make the new HDR EC space would be. That process will directly be ported to the S and 5, and I think I will be able to do it much faster.

EXACTLY! Well said.

I am in agreement with you!!!
I don't understand the rebellious-teen-diva-ish tone in some of the demands of this thread that the LUT be ready at their command.  They probably don't understand that Sage is  a one man R&D team, so he has to take his time to fine tune the luts. Plus as someone pointer earlier, updates are going to roll out soon and we don't know how that might affect the LUT as well.  Sage probably has other film demands to attend to, perhaps a full time job? He owes no one any deadline schedule. 

Hi, i been busy buy but i wanted to share this short film i did last year.
The video is private, the film is now going thru festivals, so please don't make it public. But feel free to show with friends.
 
This was shot with GH5 and the used GHAlex Clog conversion, then B/W film emulation.

I mean the guy is only one person, and funding the camera rental, while nice, still doesn't pay the bills - which is where the time thing comes in, and Alex clearly has made a decision on what to do first based on the P4k demand. While that may not fit your needs, the Gh5s is becoming the minority, and I just think it is distasteful to act like he should just focus on what you want, because he said it is on the roadmap a long while back. He made no promises, and I am sure he has every intention of getting to it.
I was simply throwing some sarcasm out there.

You should probably put your money where your mouth is and fund him quitting his day job.

I'd suggest anyone stacking filters try different orders and see which order gives the least reflections.  Setup the camera on a tripod and shine a light source into the lens to really accentuate the effect and then compare images and see which has the least undesirable side-effects.

I personally have a Hoya Variable ND which has been fantastic is is very affordable.
There is IR pollution when using ND filters on the P4k, not nearly as bad as the Ursa but it is definitely there. I put the IR cut first based on some recommendations i received on filter stacking - I figure since most IR cut filters are over the sensor, it makes sense to have it first?
I use a promist 1/8 and just leave it on all the time. I feel it is a nice balance, sometimes it isn't enough, but it is never too much - and I like being able to leave it on all the time to take the edge off any harshness.
 

Thanks so much!
Indeed it seems the P6K has a unique personality of its own. I don't know when it'll be ready, but I can say it will be something special.
An idea of what I've been kicking around: I rewrote the engine to work at whatever resolution on the fly. I did this to handle unique 97x/129x resolution passes that handle 'super' values beyond floating point 0.0 - 1.0. I've entirely remade the EC component in this larger space, and will be able to offer DCI-P3 variations (massively benefits 709 conversions as well)

Please don’t advertise you’re an American, it makes the rest of us look bad.
Hahaha... just kidding. 
I’m almost convinced Skip77 (and possibly ZachGoodwin2) are alter egos of somebody on this site having a laugh.

The post you just made is trolling.  
I made no comments directed at you.
You guys don't like AMERICANS and that's all this is.  You all ran off @webrunner5 because of his views and you attack me for saying the same-things camera related comments that other people post about. 
 
You might want to create a few more new click - bait titles for your You Tube channel instead of bothering with me. 

Same thing for me. I had that troll on ignore but some how he resurfaces. 
Because you are trolling and deserve it?