A story about how I almost spent a fortune on color grading. But surely I can still fight with my current gear...?
My latest hobby is color grading in DaVinci Resolve.
Hello everyone. I'm a self-proclaimed 'Color Grading Guy'.
Actually, I've been really hooked on color grading in DaVinci Resolve lately. My editing skills are still a work in progress, but for some reason, I've become obsessed with adjusting colors. You know how it is, right?
I'm using a Sony a6400, and I'm enjoying fine-tuning the settings little by little.
Beyond 'That looks great!'
Something happened the other day. I sent a video of a camping trip to a friend, and they said, 'That looks great!'
I got so happy that I thought, 'Alright, I'm going to make it look even cooler!' and I put a lot of effort into the color grading.
And then...
'Wait, what?'
The gradient in the sky looked a bit off. Some kind of block noise started appearing.
The expert in my head starts whispering.
Expert: 'That's the limit of 8-bit.'
Me: 'Huh?'
Expert: 'If you want to create better footage, you might need a 10-bit compatible camera.'
Me: 'Seriously...?'
But wait... is that really the case?
Could it be that I still don't fully understand the a6400?
Is this really the limit of 8-bit? Am I truly drawing out the full potential of the a6400 as it stands??
I checked the settings for this footage, and it was recorded in PP7, S-Log2, S-Gamut.
I asked ChatGPT (I've been asking it everything lately), and apparently, to bring out the true value of the a6400, PP8 S-Log3, S-Gamut3.Cine is better.
Oh... this is embarrassing. I'm still not using the camera's full performance, am I? I feel bad for the a6400 if I keep this up.
I tried reading Sony's official website.
Since I've come this far, I have no choice but to get to the bottom of it. I opened Sony's official help guide.
Using Picture Profile presets This camera has video settings pre-registered in [PP1] to [PP10] to match shooting conditions.
MENU → (Shooting Settings 1) → [Picture Profile] → Select the desired setting.
PP1: Setting example using [Movie] gamma
PP2: Setting example using [Still] gamma
PP3: Setting example for natural tones using [ITU709] gamma
PP4: Setting example for tones faithful to the ITU709 standard
PP5: Setting example using [Cine1] gamma
PP6: Setting example using [Cine2] gamma
PP7: Setting example using [S-Log2] gamma
PP8: Setting example using [S-Log3] gamma and S-Gamut3.Cine color mode
PP9: Setting example using [S-Log3] gamma and S-Gamut3 color mode
PP10: Setting example for HDR shooting using [HLG2] gamma
Hmm, I see, I see?
Gamma:Select a gamma curve.
- Movie: Standard gamma curve for movies
- Still: Standard gamma curve for still images
- Cine1: Softens the contrast in dark areas and clarifies gradation changes in bright areas to create a calm-toned image (equivalent to HG4609G33).
- Cine2: Provides almost the same effect as [Cine1], but select this when you want to handle it within 100% of the video signal for editing, etc. (equivalent to HG4600G30).
- Cine3: Strengthens the contrast between bright and dark areas compared to [Cine1], and clarifies gradation changes on the black side.
- Cine4: Strengthens the contrast in dark areas even more than [Cine3].
- ITU709: Gamma curve equivalent to ITU709.
- ITU709(800%): Gamma curve for scene confirmation assuming [S-Log2] or [S-Log3] shooting.
- S-Log2: [S-Log2] gamma curve. Settings assuming image processing after shooting.
- S-Log3: [S-Log3] gamma curve. A gamma curve with characteristics more similar to film, assuming image processing after shooting.
- HLG: Gamma curve for HDR shooting. Characteristics equivalent to Hybrid Log-Gamma, which is an HDR standard, ITU-R BT.2100.
- HLG1: Gamma curve for HDR shooting. A mode that prioritizes noise reduction. However, the dynamic range that can be shot is narrower than [HLG2] and [HLG3].
- HLG2: Gamma curve for HDR shooting. Settings that consider the balance between dynamic range and noise.
- HLG3: Gamma curve for HDR shooting. Settings for when you want to shoot with a wider dynamic range than [HLG2]. However, the noise level increases.
* [HLG1], [HLG2], and [HLG3] are gamma curves with the same characteristics, but with different balances of dynamic range and noise. The maximum value of the output video level differs for each: [HLG1]: 87%, [HLG2]: 95%, [HLG3]: about 100%.
...Hmm, I see, I don't get it (lol)
From PP1 to PP10, it seems there are various settings. Movie, Still, ITU709, Cine1, Cine2... Do the pros understand all these differences?
What does this even mean... Which one has the widest dynamic range setting after all???
I found a technical summary regarding Sony's S-Log, so I will quote a part of it.
"S-Gamut3.Cine/S-Log3" is designed to be more Cineon-like than the previous S-Log2, and its color reproduction is closer to scanned negative film from film shooting. The color gamut is set slightly wider than the DCI-P3 color gamut so that graders can easily adjust it in the post-production process, and the tone curve provides richer gradation expression in dark areas than S-Log2, taking compatibility with traditional Cineon workflows into account more than ever before. In contrast, "S-Gamut3/S-Log3" can capture the maximum color gamut possible with each camera and record it as a digital negative. The color gamut of S-Gamut3 is the same as the original SGamut, but further improvements have been made in color reproduction.
S-Log3 is designed based on the Cineon digital negative revised in 2007. S-Log3 does not have the shoulder characteristics unique to film, and there is almost no foot part in the dark areas. As shown in the figure below, S-Log3 is designed to be even more Cineon-like than S-Log2, and is designed to be more intuitive to grade when grading in log space than S-Log2.
"Let's experiment" strategy
Since I can't understand it just by theory, I decided to actually shoot the sky and compare them.
Applying the same color grading, I compared footage shot with S-Log2 and S-Log3.
WB, ISO, etc. are all the same settings
...Huh? Isn't the block noise actually more noticeable with S-Log3?
The degree of influence of the DaVinci Resolve color space
I remembered that I had set the Timeline color space to Rec.709 during video color grading, so I'm adding this note for reference.
Thinking that the block noise might be caused by this setting, I tried matching the color space to S-Log2.
I only changed the color space in the project settings, and the results obtained are as follows.
What do you think?
Overall, it has become darker and the gradation is relatively less noticeable, but block noise can still be confirmed, so this might be the limit of my editing.
In the case of videos, if the main goal is to upload to YouTube, since YouTube is a world of Rec.709 color space, setting the Timeline to Rec.709 has the advantage of making it easier to see if the colors will break down.
It seems there is a way to use the Color Space Transformer effectively, but when I tried it, the overall tone was too vivid and editing became difficult, so it still requires more research.
In the end, I tried tweaking various DaVinci Resolve settings, but I didn't reach a complete solution. Is this the limit of my skills, or is there some other answer...?
If there is a better way, I would really appreciate it if you could leave a comment and let me know. Please teach me, thank you very much.
Bonus: Does the camera I want support 10-bit?
While experimenting, I started wanting one more and more. A 10-bit compatible camera.
I had researched it until I was blue in the face, so I knew, but just in case, I'll re-examine the specs of the Sony a6700, Nikon Zf, and Sigma fp that I mentioned I was considering the other day.
Sony α6700
The α6700 supports internal recording in 4:2:2 10-bit format. Specifically, it is capable of shooting at up to 120fps at 4K (3840×2160) resolution. The bitrate varies depending on the recording settings, but for example, in the XAVC S-I 4K format, it is approximately 600Mbps for 4K 60p and approximately 300Mbps for 4K 30p.
Nikon Zf
The Nikon Zf supports internal 10-bit recording in H.265 format. At 4K UHD (3840×2160) resolution, it can shoot at frame rates of 60p, 50p, 30p, 25p, and 24p. The bitrate is approximately 340Mbps for 4K 60p and approximately 190Mbps for 4K 30p.
Sigma fp
The Sigma fp supports 12-bit RAW video recording in CinemaDNG format. By using an external SSD, it is possible to shoot at up to 29.97fps at UHD 4K (3840×2160) resolution and up to 100fps at FHD (1920×1080) resolution. The bitrate is approximately 2980Mbps for UHD 4K 12-bit 29.97fps and approximately 2530Mbps for FHD 12-bit 100fps.
(Especially, isn't the Sigma fp's 12-bit RAW shooting just amazing? I know it's over-spec, but...)
My wallet: "Please stop... not there... stop..."
Bonus 2: Which modes on the a6700 support 10-bit?
Sony α6700
Achieving high quality in grading using footage recorded with Log shooting
Equipped with S-Log3, which achieves a wide latitude of 14+ stops (*) and gradation characteristics from shadows to midtones (18% gray). The color gamut supports S-Gamut3 and S-Gamut3.Cine. To obtain high-resolution and high-quality textures, we emphasize the characteristics of the footage shot with this camera and make adjustments to make it easier to create high-quality video in post-production after Log shooting.
Also supports HLG (Hybrid Log-Gamma) with 4:2:2 10-bit recording
Equipped with HLG (Hybrid Log-Gamma) as a picture profile preset. By connecting the shot footage to an HDR (HLG) compatible TV via HDMI and playing it back, you can enjoy realistic images close to the naked eye with suppressed crushed blacks and blown-out highlights without color grading. It supports the wide color gamut BT.2020 color space, and with 10-bit fine gradation reproduction, you can display richer and more high-definition images than ever before.
It's hard to tell from the spec sheet, but it seems to support 10-bit 4:2:2 in both S-Log3 and HLG.
Summary: My experiments will continue!
Now, for everyone who has read this far. Actually, even as I write this article, I am still searching for new experimental methods.
Don't you all have similar experiences?
- I feel like I can take better footage with my current gear
- But I also want a new camera
- I wonder if these color grading settings are correct...
What I'm particularly curious about:
- What settings do you all use for S-Log3 shooting?
- If anyone has mastered the Color Space Transformer, please let me know!
- Also, does anyone know a solution to this "sky block noise problem"?
Please let me know in the comments!
(And please stop my "I think I'll buy a camera" disease... lol)