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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Gamma 2.4? Or 2.2?

Stephen Pruitt

Stephen Pruitt

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Hi all. . .

I just sent my Flanders CMC171 monitor in for recalibration, and it came back with a normal gamma of 2.4. I asked about this, and Flanders said "that's what things are going to" or something like that.

And yet I've always heard that 2.2 is the appropriate gamma.

What say ye, kind souls?

Thanks.

Stephen
 
Okay, great! Thanks, Marc!

I really appreciate it.

Stephen
 
i think you can switch to 2.2 within the flanders.

my experience is that although 2.4 is the technical "correct" gamma to use - 2.2 will normally give you less head ache, because alot of clients now approve online, and most computer monitors are 2.2.

in regards to DCP, i believe the way EasyDCP in Resolve handles the gamma and color correction to the DCP specs from a rec709 - is from gamma 2.2 to 2.6 (DCI compliant.)
 
Okay, Sidney, this could be crucial. I'm primarily looking to release our film online. Should I therefore set my monitor to 2.2?

My major issue, and the one I'm struggling mightily with, is that whereas things look amazing on my monitor (using the CM171 on a Wintel machine) and terrific on my Macbook Pro computer, it looks like absolute CRAP on my Samsung LCD TV (which is just your ordinary set set to "cinema"). DVDs look terrific on the tele, but my "correct" color looks unwatchably bad.

I am seriously as the end of my rope dealing with all this!

Thanks.

Stephen
 
Are you sure your issue is with gamma? The difference between 2.2 and 2.4 is near black and is how fast you come out of black. If you master for 2.2. and show on a 2.4 display, then you will see more shadow detail. If you master at 2.2 and show at 2.4, then you may crush near black.

Playing video content on the PC out to a consumer TV also deals with video level differences between PC (0, 255) and TV (16, 235).

One option, if you want to go through the trouble, is to install MPC (Media Player Classis) with madVR as the renderer. Then in madVR you can switch between video and PC levels. This even supports true 10-bit now, if you have 10-bit HEVC encoded files.

You also have to deal with RGB vs. YCbCr and these may use different default video settings in the display as well as different memories. e.g. You may calibrate from a DVD player using YCbCr output and then the PC may use RGB output and a completely different memory with different settings.

Have you tried burning to a DVD/BD and then playing back in a consumer player? In this case, it assumes the authoring software does the right thing as well.

There are facilities (GDMX, Deluxe, etc...) that do this full time and know what they are doing. They test and test and test on various displays, check levels, etc... They also use better encoders than what you might find in Adobe or Apple products, but that is not your problem here.
 
Sidney L. Plaut said:
in regards to DCP, i believe the way EasyDCP in Resolve handles the gamma and color correction to the DCP specs from a rec709 - is from gamma 2.2 to 2.6 (DCI compliant.)
Click to expand...

EasyDCP lets you change the gamma to 2.4 if you like, but you'd have to edit a couple of text files.
 
Roger Singh said:
EasyDCP lets you change the gamma to 2.4 if you like, but you'd have to edit a couple of text files.
Click to expand...

ok ok, but I like to avoid that and use as little energy as possible:)

Stephen,

there are ofcourse a million ways to get to Rome, and you can use a lot of money and time on it, but I know you are an indie filmmaker doing your features,
we just finished my first feature film - Dark Samurai, which was selected last year for Camerimage in the cinematographers debut.

After talking to Fraunhofer institute, the makers of easy DCP and a bunch of post houses, we decided to stay in rec709 gamma 2.2, to let Easy DCP do the transform into XYZ gamma 2.6, which it does perfectly.
I tested the DCP in 3 theaters and it looked fantastic. - ofcourse there are differences between a silver screen, a 2K or 4K projector etc... but the DCP looked exactly like it did in resolve on my Sony Monitor.

It is definitely a very simple workflow. and being in rec709 you are ready for the blu-ray/ VOD version as well.

But as I said there are many ways to get your film finished.

-
 
God this stuff is hard. Wish I had more money to hire someone to do it for me. But I don't. So here I am.

One last clue: The film looks UTTERLY HORRIBLE when playing the files in Windows Media Player. I've been burning just 1080p AppleTV H.264 files to play on our MacPro and TV (via USB). But playing the AppleTV files on the Windows Media Player everything looks completely washed out.

I feel like if I had one reliable target (CM171), I could get a really great look. Unfortunately, the target (computer, TV, etc.) keeps changing. Somehow DVDs look good on everything. That's what I'm trying to do.

Thanks gents.

Stephen
 
well if your are also changing from RGB to YUV depending on what codec's you are exporting to - that will also affect everything. - forinstance in resolve 10, if I export r3d to prores444 everything is correct - if i export to a YUV codec like prores 422HQ the colors/ gamma is not correct. - so export to a RGB codec or DPX and encode from that in another program.
 
As Sidney points out, the issue when converting RGB to YUV can be the level problem (16, 235 -> 0, 255 / visa versa) or 601 vs. 709 3x3 color matrix.

As an interesting point, Netflix, Amazon and Microsoft all use the HD source to create their SD assets and they are all 709 now. By that I mean the SD content on those services expects the 709 3x3 matrix on playback because they are simply scaling the HD source to SD resolution and no longer twisting the color space.

Stephen, what is your workflow? What is the final product you are outputting your content from? e.g. FXP, Resolve, Premiere Pro, etc... How are you playing it back on the TV? Which software? If you wanted to provide me a 1-minute piece of your content, I can try and get it encoded properly so you can try and play it back on a CE device and see how it looks. At least try and help you find a better workflow.
 
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