How to grade footage for WEB distribution?

[jakub_friso]

Hello guys, I was grading some short clips in my new setup with professional color grading monitor to test it out and I have posted them to web to see if I am well calibrated for the web and I have to say that both on Youtube and Vimeo the clips looked very different - little different in colors and absolutely awful in terms of gamma and black level... As the clips looked pretty accurate on other consumer monitors, except they were little brighter because they were LCDs and I was grading on OLED monitor, the web destroyed everything...
I know that I cant do much in terms of that HTML5 web decoding but I was wondering till what point I can still affect how the video will look on the web and how much can I do about it till its still in my hands?
Do I have to adapt my workflow for the web distribution?

Please, if you would show me some article that focuses on this topic I would really appreciate it.

thank you

 

[movie-grinder.com]

when you do color grading, then it is important to know that different distribution channels have different color spaces. web, tv and cinema are different in terms of color. when you are grading on a tv reference monitor then you need to know that tv expects lifted blacks and a lowered whites. the tv hardware then applies a "color correction" to the footage and lowers the blacks again and lift the whites. these are broadcast legal colors.
when you watch your footage on a computer screen, no matter if is is an ipad, or laptop or desktop pc then your blacks are gray and your whites are not white, your footage looks a little dull. the color space on a computer is called srgb and it expects a color range where black is 0 and white is 255 (in 8bit terms).
so if you expect your colors to look the same if you are watching it on a tv and on a computer, you need two different color corrections.
using a broadcast reference monitor is a very good thing when you work on commercials or tv shows or what ever tv content, but it is not the best idea when you want to distribute on the web. for that purpose i use a sony oled ref monitor AND a ref computer monitor (in my case the eizo fs-2333, that is ridiculously cheap but excellent for that purpose).
when you know that you need your footage for both, tv and web, it is a good idea to do the grading in srgb full range first and then do a conversion to rec709 (broadcast legal), coz when you do it the other way round, you can easily create banding, especially when working in 8bit. in these days where 10bit or higher is the standard it might be not so important to watch out for banding, but still, is is the nicer approach to create a master with the higher amount of data first, and then create the lower data versions from there.

i hope this is helpful, i've tried to simplify as much as possible.

 

[jakub_friso]

Well to be honest, I am kinda confused I based my knowledge on this article from RED
http://www.red.com/learn/red-101/cinema-color-management

where they say that sRGB and Rec709 have nearly similar color space ITU Rec.709
I am using Sony Oled Monitor Trimaster EL and based on that article I have set it show me color space ITU Rec.709
which, to my knowledge should be similar to the sRGB colorspace so I was expecting that I am correctly calibated and only difference that I should expect will be that it will be slightly brighter on the regular monitor because LCD cant display 100% black

is that correct?

 

[movie-grinder.com]

ok we are talking about two slightly different things here. sRGB and Rec709 are somewhere in the same area when we talk about the screen gamma. and they are only in the same area when you compare that to linear or log. the difference between sRGB and Rec709 is very very noticable when you compare them directly. but however, the more obvious difference between tv and web is that tv works from 16-235 (not 100% sure about these numbers, google it if you want to know 100%correctly) while web works from 0-255 (all 8bit terms - not 100% correct coz tv works with voltages but precise enough to explain). now when you send a picture with a color range of 16-235 to a tv, then the hardware knows 16 equals all light off - so it is black. and it knows 235 equals all light full power - so it is white. now you take these broadcast legal colors with a Rec709 gamma (that makes the picture a little darker than sRGB gamma) and you display it on a computer screen. then the first thing you notice is that the black is not black, it is dark gray, coz for a computer 0 equals all lights off and 16 equals - make it a dark shade of gray. same goes for the light, 235 is not white on a computer screen - 255 is white so the same image on the computer screen looks a little less contrasty, then the Rec709/sRGB gamma comes into play and reduces the contrast a little more. so you end up with two completely different looks. now all the 0-255 is 8bit rgb talk, in 10bit it would be 0-1024 and when you talk with vfx guys then we talk 0-1, and a broadcaster talkes in voltages, but the principle is always the same.