Color space transform vs Conversation LUT

[Shylesh Kumar]

Can I use colorspace transform instead of a conversation lut ? What are the differences here? 

I am hoping someone will shed some light on this for me.

Thanks

[Anton Meleshkevich]

3D LUT often contains not a precise math for color space transform but more artistic changes like s-curve, highlights compression and soft clipping, saturation remapping and sometimes more. And usually it clips highlights above 100 IRE (actually not IRE of course, I mean above 1024 on Resolve waveform monitor).

But color space transform ofx also can do some of these things.

I prefer to use color space transform for from log to another log conversions. And I often use new arri log to rec709 LUT from their website for from log to rec709 conversions. But I use color space transform with luminance and saturation (sometimes) mapping as well. It all depends on  footage and desired look.

[Adam Fiori]

On 6/16/2020 at 8:40 AM, Shylesh Kumar said:

Can I use colorspace transform instead of a conversation lut ? What are the differences here? 

I am hoping someone will shed some light on this for me.

Thanks

It’s really a matter of what gets you to your destination. However, there's and advantage to using a color space transform as it gives you more control and you aren’t locked or bows on by the fixed nature of a LUT.  CST vs the camera’s official log to Rec.709 LUT will be a bit different, though you may prefer one over the other visually, neither is absolute. 
 

Resolves CST is quite flexibility and can be dialed in (sat and luminance mapping,) however, an alternate method is to roll your own log to Rec.709 conversion using your grading tools. 
 

Edited July 7, 2020 by Adam Fiori