Log shooting

[sh1209]

So I think I have it figured out finally. I disabled the 709 conversion, did the corrections then applied the LUT and dialed it back a bit last. To me it looks dead on accurate to what I am seeing in the room

You can only see EXIF info for this image if you are logged in.

 

[Alistair]

So I think I have it figured out finally. I disabled the 709 conversion, did the corrections then applied the LUT and dialed it back a bit last. To me it looks dead on accurate to what I am seeing in the room
View attachment 105265

Yes that would work. Without that initial Rec.709 conversation it probably defaults to a wider intermediate space/gamma in which your edits are performed. The LUT then converts the edited footage to Rec.709.

 

[PhilcTx]

Looks like you're there. Good.

Out of curiosity I checked the instructions I received with my Phantom LUTs for their FCP settings. (I use DR). I usually apply the Phantom neutral ARRI LUT that provides a Rec709 look.

Phantom's instructions for use with FCP:

- In Library Properties: click Modify then select Standard Gamet SDR for color processing.
- Once LUT is added ensure Input and Output are both set to Rec.709 in the Custom LUT toolbar.
- FCP is natively Tetrahedral by default so should be no issues it says.

Dunno if that applies to the Sony 709 LUT or not.... but thought it might be of interest.

 

[sh1209]

Looks like you're there. Good.

Out of curiosity I checked the instructions I received with my Phantom LUTs for their FCP settings. (I use DR). I usually apply the Phantom neutral ARRI LUT that provides a Rec709 look.

Phantom's instructions for use with FCP:

- In Library Properties: click Modify then select Standard Gamet SDR for color processing.
- Once LUT is added ensure Input and Output are both set to Rec.709 in the Custom LUT toolbar.
- FCP is natively Tetrahedral by default so should be no issues it says.

Dunno if that applies to the Sony 709 LUT or not.... but thought it might be of interest.

I will definitely check that out. I have contemplated buying phantom luts. I’ve seen a lot of good reviews about them. I’m assuming you like them pretty well?

 

[MotoPixel]

I've posted this video before, but a review might be in order for some here...lots of good general purpose info that can apply to making sure whatever editing/color grading system you use is properly managing color space and gamma through the editing pipeline. I wish I had run across this 4 years ago when I had to ferret out this info from a variety of sources. The concepts discussed here apply no matter what camera you're shooting with, though some of the methods of managing color workflow are more Resolve specific. Once you understand the concepts, you should be able to apply to FCP or Premier implementations of color management.

One of the bugaboos that plagued me at the start was LUTs...and now I avoid them like a plague...unless...unless Resolve doesn't have internal support for a specific log format internally. In my case, there is DJI Dlog-M that is the log output of my Mavic 2 Pro or Action 5 Pro. I was confounded because I kept trying to apply the Nikon LUTs when DaVinci had already done the conversion automatically because I was initially using Automatic Color Management. Sounds similar to what Steve and others have been dealing with in FCP. One other thing about LUTs that many don't understand...you have to feed them what they're expecting as an input. You can't feed a LUT expecting a Rec.709 format stream with a Rec.2020 color space and log gamma...you'll get a very weird result. If you edit in a wide-gamut color space/gamma, like DaVinci Wide Gamut Intermediate, you have to convert back to Rec.709 before sending the content into a LUT designed for Rec.709. Likewise there are LUTs designed to work with DWG/I, not Rec.709. Many of the LUT's out there aren't really transparent as to what they're expecting.

 

[sh1209]

I've posted this video before, but a review might be in order for some here...lots of good general purpose info that can apply to making sure whatever editing/color grading system you use is properly managing color space and gamma through the editing pipeline. I wish I had run across this 4 years ago when I had to ferret out this info from a variety of sources. The concepts discussed here apply no matter what camera you're shooting with, though some of the methods of managing color workflow are more Resolve specific. Once you understand the concepts, you should be able to apply to FCP or Premier implementations of color management.

One of the bugaboos that plagued me at the start was LUTs...and now I avoid them like a plague...unless...unless Resolve doesn't have internal support for a specific log format internally. In my case, there is DJI Dlog-M that is the log output of my Mavic 2 Pro or Action 5 Pro. I was confounded because I kept trying to apply the Nikon LUTs when DaVinci had already done the conversion automatically because I was initially using Automatic Color Management. Sounds similar to what Steve and others have been dealing with in FCP. One other thing about LUTs that many don't understand...you have to feed them what they're expecting as an input. You can't feed a LUT expecting a Rec.709 format stream with a Rec.2020 color space and log gamma...you'll get a very weird result. If you edit in a wide-gamut color space/gamma, like DaVinci Wide Gamut Intermediate, you have to convert back to Rec.709 before sending the content into a LUT designed for Rec.709. Likewise there are LUTs designed to work with DWG/I, not Rec.709. Many of the LUT's out there aren't really transparent as to what they're expecting.

Thank you I will check it out.

 

[Alistair]

Thanks for this great information. Like Steve, I'm keen on not giving up on Log and getting through the knotholes. Would you mind if jumped in from time to time and asked a Canon specific question, such as checking with you about my colour management set up in Davinci Resolve?
Rudy

These settings at the project level will get you started, lots of other ways to do it but they are all doing the same thing. In the Input color space gamma setting you have the options of Canon Log, Canon Log 2, Canon Log 3. Just choose whatever one you are using. Then apply your basic exposure, contrast and saturation adjustments in the colour tab. See if you prefer the results to non-log footage.

 

[PhilcTx]

I will definitely check that out. I have contemplated buying phantom luts. I’ve seen a lot of good reviews about them. I’m assuming you like them pretty well?

Yes - very pleased. I use the LUT with all 3 of my Sony's that are set to use S-Log3 S-Gamut3.Cine

Really simplified color grading and consistency for me when I use their LUT with a DR Node Tree template.

 

[sh1209]

Yes - very pleased. I use the LUT with all 3 of my Sony's that are set to use S-Log3 S-Gamut3.Cine

Really simplified color grading and consistency for me when I use their LUT with a DR Node Tree template.

So you still do all your exposure contrast setting first correct? Then apply the Lut last?

 

[PhilcTx]

So you still do all your exposure contrast setting first correct? Then apply the Lut last?

My DR Node Tree has 6 serial Nodes.

1st Node is to correct any exposure clipping
2nd Node is where the LUT is applied.
3rd Node is for minor exposure adjustment
4th Node for small contrast changes
5th Node for small color balance adj
6th Node for applying small amt sharpening

Resolv's Color Management is set per Phantom to Color Science DaVinci YRGB; Timeline color space Rec709; Output color space same as Timeline, and 3D lookup table interpolation Tetradedral

 

[sh1209]

My DR Node Tree has 6 serial Nodes.
1st Node is for larger exposure/contrast adjustments in case of over-exposure etc.
2nd Node is where the LUT is applied.
3rd Node is

Not sure what a node is but I’m assuming it’s like a layer in FCP

 

[PhilcTx]

Not sure what a node is but I’m assuming it’s like a layer in FCP

I assume so - but I've never used FCP.

 

[sh1209]

I assume so - but I've never used FCP.

I really think I finally have a handle on this now finally. One of the biggest mistakes I have been making is applying the LUT first in the workflow which is a no no. As far as exposing, dual iso values and all of that I am good with. I was basically setting myself up for failure right out of the gate with the lut. Thanks for your help and suggestions

 

[NikonshooterRTFan]

I'd like to see some A - B comparison between an edited LOG video and a SOOC standard video where someone prefers the LOG. Some of the examples here look fine, but I'm not convinced they are "better" than the standard shooting profile, or that it's worth the time and work involved to shoot LOG. It's been a while since I looked into this but a year or 2 ago when I did, I couldn't find any examples where LOG was noticably superior.

Also when you are shooting a house interior with bright sunlight coming through the windows, keep in mind that is a specific scene that is always going to involve compromises in correctly exposing for either highlights or shadows at the expense of the other. It's the shooter's choice which to emphasize and the LOG profile which is going to underexpose is going to make the outdoor areas look better, but at the expense of failing to ETTR the rest of the scene.

I think the bottom line is that LOG (along with the other less commonly used modes) is a specific setting that works for niche scenarios, but for daily / typical / standard scenes there is a reason the color science engineers picked the "standard" profile that they programmed.

Whenever I've viewed these side by side typical daytime comparisons, the differences are either marginal or I actually prefer the standard versions. Here, out of 4 scenes (which look VERY similar) in many scenes the old GoPro 10 footage looks the best and the GoPro 12 HDR looks the worst! (I realize LOG shooting is not the same as HDR but both are altered color / exposure modes and I feel the same about both).

For me LOG is either Emperor's New Clothes, or it just presents an image tone that I don't care for, or I just don't shoot in the specific scenarios that it benefits from.

 

[sh1209]

I'd like to see some A - B comparison between an edited LOG video and a SOOC standard video where someone prefers the LOG. Some of the examples here look fine, but I'm not convinced they are "better" than the standard shooting profile, or that it's worth the time and work involved to shoot LOG. It's been a while since I looked into this but a year or 2 ago when I did, I couldn't find any examples where LOG was noticably superior.

Also when you are shooting a house interior with bright sunlight coming through the windows, keep in mind that is a specific scene that is always going to involve compromises in correctly exposing for either highlights or shadows at the expense of the other. It's the shooter's choice which to emphasize and the LOG profile which is going to underexpose is going to make the outdoor areas look better, but at the expense of failing to ETTR the rest of the scene.

I think the bottom line is that LOG (along with the other less commonly used modes) is a specific setting that works for niche scenarios, but for daily / typical / standard scenes there is a reason the color science engineers picked the "standard" profile that they programmed.

Whenever I've viewed these side by side typical daytime comparisons, the differences are either marginal or I actually prefer the standard versions. Here, out of 4 scenes (which look VERY similar) in many scenes the old GoPro 10 footage looks the best and the GoPro 12 HDR looks the worst! (I realize LOG shooting is not the same as HDR but both are altered color / exposure modes and I feel the same about both).

For me LOG is either Emperor's New Clothes, or it just presents an image tone that I don't care for, or I just don't shoot in the specific scenarios that it benefits from.

Yeah I have definitely had my doubt as well but for me it is more wanting to learn how correctly than it is to state it's superior. Most of the time I will continue to use the standard profile but in troublesome lighting situations, I can see log possibly having an advantage. Most of the time in good lighting the camera definitely does a great job on its own.

 

[Rudy Pohl]

These settings at the project level will get you started, lots of other ways to do it but they are all doing the same thing. In the Input color space gamma setting you have the options of Canon Log, Canon Log 2, Canon Log 3. Just choose whatever one you are using. Then apply your basic exposure, contrast and saturation adjustments in the colour tab. See if you prefer the results to non-log footage.

View attachment 105269

Alistair,

Could you have a look at my setup please?
After watching some Youtube videos on Log editing I've been using Color Space Transform as the final node in my node tree in Davinci Resolve. I use a Canon R5 shooting C-Log3 and the colour space is Canon Cinema Gamut. I input the below information into the CST form.
Is this OK and if not what should I be doing differently?
Thanks,
Rudy

Color Space Transformation
- Input Color Space: Canon Cinema Gamut
- Input Gamma: Canon Log 3
- Input Color Space: Rec709
- Output Color Space: Rec709
- Tone Mapping Method: Davinci

 

[Alistair]

Alistair,

Could you have a look at my setup please?
After watching some Youtube videos on Log editing I've been using Color Space Transform as the final node in my node tree in Davinci Resolve. I use a Canon R5 shooting C-Log3 and the colour space is Canon Cinema Gamut. I input the below information into the CST form.
Is this OK and if not what should I be doing differently?
Thanks,
Rudy

Color Space Transformation
- Input Color Space: Canon Cinema Gamut
- Input Gamma: Canon Log 3
- Input Color Space: Rec709
- Output Color Space: Rec709
- Tone Mapping Method: Davinci

Hi Rudy, Using this CT, what are your colour management settings in the project settings? Are you applying edits before, after or in the CT? BTW I assume your third bullet point is a typo and should be Output Gamma: Gamma 2.4.

But depending on your project settings, you may be converting straight from Canon to Rec709 with no intermediate colour space for editing. But DVR may be handling it under the hood, its hard to tell. If DVR is not handling it, you will be unnecessarily restricting your working colour space.

To make sure, try using 3 nodes:

Node 1: CT node:
- Input Color Space: Canon Cinema Gamut
- Input Gamma: Canon Log 3
- Output Color Space: DaVinci Wide Gamut
- Output Gamma: DaVinci Intermediate

Node 2: Your edits

Node 3: Another CT node:
- Input Color Space: DaVinci Wide Gamut
- Input Gamma: DaVinci Intermediate
- Output Color Space: Rec709
- Output Gamma: Gamma 2.4

Your project settings colour management should then be:

I suspect what you will see, compared to the settings you describe above, is that your footage will look a lot flatter before edits. However there will be far more editing latitude in the file to apply contrast, saturation and exposure adjustments. You can try making rather heavy handed adjustments and see how the footage holds up, it should hold a lot more colour information if my suspicions are correct.

Incidentally, the project settings I showed in my previous post able achieve the same as the two CT nodes I describe above in this post.

Regards.

 

[Rudy Pohl]

Hi Rudy, Using this CT, what are your colour management settings in the project settings? Are you applying edits before, after or in the CT? BTW I assume your third bullet point is a typo and should be Output Gamma: Gamma 2.4.

But depending on your project settings, you may be converting straight from Canon to Rec709 with no intermediate colour space for editing. But DVR may be handling it under the hood, its hard to tell. If DVR is not handling it, you will be unnecessarily restricting your working colour space.

To make sure, try using 3 nodes:

Node 1: CT node:
- Input Color Space: Canon Cinema Gamut
- Input Gamma: Canon Log 3
- Output Color Space: DaVinci Wide Gamut
- Output Gamma: DaVinci Intermediate

Node 2: Your edits

Node 3: Another CT node:
- Input Color Space: DaVinci Wide Gamut
- Input Gamma: DaVinci Intermediate
- Output Color Space: Rec709
- Output Gamma: Gamma 2.4

Your project settings colour management should then be:
View attachment 105275

I suspect what you will see, compared to the settings you describe above, is that your footage will look a lot flatter before edits. However there will be far more editing latitude in the file to apply contrast, saturation and exposure adjustments. You can try making rather heavy handed adjustments and see how the footage holds up, it should hold a lot more colour information if my suspicions are correct.

Incidentally, the project settings I showed in my previous post able achieve the same as the two CT nodes I describe above in this post.

Regards.

Thanks Alistair,

Here's screenshot of my CST form in DR 19.

https://live.staticflickr.com/65535/54270819534_3501df3178_h.jpg

Sorry for providing only this link, I can't figure out how to post a private Flickr image here. Plus I have to run away for a couple of hours. I'll continue later tonight or tomorrow.
Thanks a million for your help,

UPDATE, I forgot to mention that I'm using the free version of Davinci Resolve which won't import Log files so I had to transcode them all first to Rec709, and then import them into Resolve. Is that a problem?

Rudy

 

[Alistair]

Thanks Alistair,

Here's screenshot of my CST form in DR 19.

https://live.staticflickr.com/65535/54270819534_3501df3178_h.jpg

Sorry for providing only this link, I can't figure out how to post a private Flickr image here. Plus I have to run away for a couple of hours. I'll continue later tonight or tomorrow.
Thanks a million for your help,

UPDATE, I forgot to mention that I'm using the free version of Davinci Resolve which won't import Log files so I had to transcode them all first to Rec709, and then import them into Resolve. Is that a problem?

Rudy

Yes, that matters. Then you are not actually working with log footage, it's Rec709. I believe you can edit 8 bit log files up to 4k in the free version. If approval is forthcoming from the finance department, the investment in Studio version is sound.

 

[Alistair]

Alistar,
Yes, I have no doubts that DR Studio is very sound investment. My problem is that my wife and I are in our mid 70s on a quite small fixed income and my fairly recent Canon R5 kit and lenses has already blown my budget for the foreseeable right out of the water. There are still other necessary things I still need to buy such as a decent 4K monitor suitable for editing. DR Studio here in Canada is over $500 and a big chunk of change for me. I'm sure I'll get there, but other things like a decent monitor are more pressing.

So my question is this: The transcoding I do to my log files makes them into Apple ProRes 422 HQ files which Resolve accepts and edits apparantly just fine. Is it still possible for me to do useful editing using these ProRes files as the inputs, and if so can you suggest how I should set up my colour management or my CST? I'd hate to have to give up working with log altogether until I can afford to get the DR Studio version.

Thanks,
Rudy

Totally understand regarding the budget, very familiar territory!

Regarding ProRes, that should be fine but I think the free version is limited to 8 bit and 4k. Also the Pro Res file will likely not be carrying camera metadata so you will need to tell DVR what the the footage has been shot on. It probably won't be able to recognise it otherwise. Has it transcoded to Pro Res as log footage with the log gamma curve? Does it have the same washed out look?

 

[Rudy Pohl]

Yes, that matters. Then you are not actually working with log footage, it's Rec709. I believe you can edit 8 bit log files up to 4k in the free version. If approval is forthcoming from the finance department, the investment in Studio version is sound.

Now that I've thought it through, as far as I understand this it's pointless for me to continue if Rec709 is my starting point, which it is. Rec709 is supposed to be the output, n0t the input. There's no point in continuing, but I need to simply return to just editing my h.264 4:2:0 files in DR as before until my budget allows me to get the Studio version.

Thanks,
Rudy

 

[Alistair]

Now that I've thought it through, as far as I understand this it's pointless for me to continue if Rec709 is my starting point, which it is. Rec709 is supposed to be the output, n0t the input. There's no point in continuing, but I need to simply return to just editing my h.264 4:2:0 files in DR as before until my budget allows me to get the Studio version.

Thanks,
Rudy

Yes, if the Pro Res file has been converted away from the Canon log gamma and Canon Cinema colour space, it is not worth pursuing. The other issues with the free version is that you are limited to 4k and 8 bit. Your R5 deserves better, it has some of the best video codecs available, including 12 bit 8k raw if I am not mistaken. At a minimum I feel you need to be at 10 bit for nature video.

 

[Rudy Pohl]

Totally understand regarding the budget, very familiar territory!

Regarding ProRes, that should be fine but I think the free version is limited to 8 bit and 4k. Also the Pro Res file will likely not be carrying camera metadata so you will need to tell DVR what the the footage has been shot on. It probably won't be able to recognise it otherwise. Has it transcoded to Pro Res as log footage with the log gamma curve? Does it have the same washed out look?

Gosh now I'm totally confused as to what to do. The youtuber whose tutorial showed us how to create a batch file to transcode or R5 log files said it converted them to ProRes files. When I load then into DR and check the info button on the colour page it says the are Apple ProRes 422 HQ files. Does that mean they're Rec709 or not? And does that mean I should still bother trying to grade them?

When I use the CST on the final node in the tree it turn a flat lifeless log-like image in a nice colourful one. Then when I edit in primaries (Exposure, WB, Contrast) I get some lovely colours that are quite presentative of the pre-sunset sky as I remember it. The only thing I can't get it to do is "pop", but then again it was a very subtle muted sky at the end of the day with dim light.

I'm really at a loss what to do.

Rudy

 

[Rudy Pohl]

Yes, if the Pro Res file has been converted away from the Canon log gamma and Canon Cinema colour space, it is not worth pursuing. The other issues with the free version is that you are limited to 4k and 8 bit. Your R5 deserves better, it has some of the best video codecs available, including 12 bit 8k raw if I am not mistaken. At a minimum I feel you need to be at 10 bit for nature video.

I'm so ticked because I was keeping my eye out for a Black Friday sale this November but every time I visited the website there was no announcement. Then suddenly they had the sale and I missed it.

 

[Rudy Pohl]

Yes, if the Pro Res file has been converted away from the Canon log gamma and Canon Cinema colour space, it is not worth pursuing. The other issues with the free version is that you are limited to 4k and 8 bit. Your R5 deserves better, it has some of the best video codecs available, including 12 bit 8k raw if I am not mistaken. At a minimum I feel you need to be at 10 bit for nature video.

Alistair,

So I did some digging, the transcoding utility I used uses ffmpeg and it converts a Canon C-log3 file into an Apple ProRes 4:2:2 10-bit file. I checked in Davinci and indeed this is the file format of all my transcoded C-log3 files that I upload and edit in the free version.

So my question is are these file worth editing in DR or should I just go back to my h.264 4:2:0 files and forget about shooting in log for now? I did a comparison last Fall of colourful male Wood Ducks with regular 8-bit vs log files transcoded as per above and the transcoded log files had noticeably richer colours.

Here's the info I could find about Apple ProRes 4:2:2 HQ files....

Apple ProRes 4:2:2 is a codec that's used in video post-production. It's known for preserving the quality of HD video.
The 10-bit encoding in ProRes 4:2:2 gives better color information.
ProRes 4:2:2 is visually lossless, meaning it retains its quality even after multiple rounds of decoding and reencoding.
ProRes 4:2:2 HQ is a version of ProRes that offers the same high quality as ProRes 4444, but for 4:2:2 image sources.

What do you think, is it worth it to continue?

Rudy