FS7: Match Canon Log3 with FS7

L

LennyLevy

Veteran
I have to shoot some interviews that were previously shot on a Canon using Canon Log3. The producer is not a tech so I don't want to burden her with questions, but I'm unfamiliar with CanonLog3.
I'm wondering if I should just shoot Slog3 and hand them a log file, or is Canon more a WYSIWYG look and I should shoot in HG7. I guess I could also make an Slog3 to Canon Log3 LUT in LuTCalc but I like too use a LUT for monitoring and then I wouldn't have a monitoring LUT.
BTW I don't have to actually match a 2nd camera, just want to give them something that won't be an outlier in Post. If they are already expecting log files then I don't want to give them HG7.

Thanks
 
LennyLevy said:
I have to shoot some interviews that were previously shot on a Canon using Canon Log3. The producer is not a tech so I don't want to burden her with questions, but I'm unfamiliar with CanonLog3.
I'm wondering if I should just shoot Slog3 and hand them a log file, or is Canon more a WYSIWYG look and I should shoot in HG7. I guess I could also make an Slog3 to Canon Log3 LUT in LuTCalc but I like too use a LUT for monitoring and then I wouldn't have a monitoring LUT.
BTW I don't have to actually match a 2nd camera, just want to give them something that won't be an outlier in Post. If they are already expecting log files then I don't want to give them HG7.

Thanks
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Canon Log 3 is almost the same as Sony SLog2. SLog2 has lower blacks, after the knee they are very similar. SLog3 is a close match to Canon Log 2 (much flatter; both similar to ARRI LogC). You can verify this using LUTCalc and reviewing the gamma curves. I'd shoot SLog2 with S-Gamut3.cine to more closely match Canon Log 3.
 
jcs said:
I'd shoot SLog2 with S-Gamut3.cine to more closely match Canon Log 3.
Click to expand...

Actually, that combination is not possible with the camera's default on-board MLUTs. And I would strongly recommend creating a custom MLUT that uses that combination because it won't match any of the post LUTs that are built into Resolve or available from Sony. If you want to use S-Gamut3.cine you must also use S-LOG3 unless you really know what you are doing in post.
 
Doug Jensen said:
Actually, that combination is not possible with the camera's default on-board MLUTs. And I would strongly recommend creating a custom MLUT that uses that combination because it won't match any of the post LUTs that are built into Resolve or available from Sony. If you want to use S-Gamut3.cine you must also use S-LOG3 unless you really know what you are doing in post.
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In Resolve you can use color space transforms where you can separate the gamma and the gamut. No need to use LUTs.
 
SLog2 + SGamut3.cine used with no LUTs to match with the C300 II and 1DX II (Lumetri in PP CC):

http://www.dvxuser.com/V6/showthread.php?346890-1DX-II-A7S-II-C300-II-Compared-Side-by-Side
https://www.youtube.com/watch?v=0Ulmgc_a39Q (see comments for settings)

I would expect the FS7 shooting SLog2 + SGamut3.cine to look fairly similar to Canon Log 3. The above examples were fairly quick to match (minutes).

SLog2 +SGamut3.cine was as close as I could get for Sony to match Canon skintones. Better than anything I tried on the FS700 (which didn't have SGamut3.cine).
 
And if colorspace transform doesnt seal it, its pretty easy matching them if you shoot a chart with both camd in the same light... and then export that as a go to 3dlut.
 
Cary Knoop said:
In Resolve you can use color space transforms where you can separate the gamma and the gamut. No need to use LUTs.
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Uh, I never said that LUTs were the only way to grade it in post. The point I was trying to make is that S-LOG2 and S-gamut3.cine is a not a possible combination to shoot onboard the camera. Apparently that point was lost on some people who do not own one of these cameras but love to tell us all about them.
 
Wow that's too bad: http://www.hingsberg.com/2017/09/crux-of-custom-and-cineei-mode/
Odd Conclusions

When all is said and done we have a very expensive set of camera’s where we actually lack the ability to access to newer gamma curve color space combinations in a way that could make more sense for specific shooting scenarios. Why on other cameras such as the A7 and A6000 series, and even the FS5, is is possible to white balance, adjust ISO, and set the gamma curve and color space to sog3/sgamut3.cine but again, not on the FS7, F5 or F55 camera?
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I sold all my Sony cameras and lenses and went full Canon (C300 II, 1DX II + L lenses) after not getting the results I was looking for with skintones. The new VENICE color science is different, and looks to be the first time since the F65 that Sony can challenge ARRI in color. The A7S III is rumored to get VENICE color filters + science, if true that would be awesome (FS5 II looks decent but sounds like it has some limitations).

If it's not possible to load a custom recording gamma / LUT with the FS7, then SLog3 + SGamut3.cine would be a good place to start matching Canon Log 3, though the footage will of course be a lot flatter (not a big deal in post if one has experience working with log gammas).
 
It's possible to bake in a LUT (MLUT typically means Monitor LUT, so best not to use that term for a baked in LUT). Thus you can in fact create a LUT to do whatever you want (e.g. outputting SGamut3.cine + SLog2 if that makes the most sense), as well as creating a Sony to Canon conversion in camera using LUTCalc (would need a bit of testing to make sure it works as expected. Wouldn't be perfect, though could get you close). http://www.xdcam-user.com/2014/12/ultimate-guide-for-cine-ei-on-the-sony-pxw-fs7/
 
I guarantee that anything that can be done with a baked-in LUT can be done better with a nice Scene File in the custom mode. Plus the scene file will give you greater control over white balance and gain. Baked in LUTs are the worst possible choice. Besides, if you shoot S-LOG2/S-gamut in the CINE EI mode you can grade it to look virutally identical to S-LOG3/S-Gamut3.cine anyway if you know what you're doing in Resolve. But if you're handing the footage over to people who don't know how the footage was shot and/or don't know how to grade properly, then all bets are off.
 
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From the OP:

I have to shoot some interviews that were previously shot on a Canon using Canon Log3. The producer is not a tech so I don't want to burden her with questions, but I'm unfamiliar with CanonLog3.
I'm wondering if I should just shoot Slog3 and hand them a log file, or is Canon more a WYSIWYG look and I should shoot in HG7. I guess I could also make an Slog3 to Canon Log3 LUT in LuTCalc but I like too use a LUT for monitoring and then I wouldn't have a monitoring LUT.
BTW I don't have to actually match a 2nd camera, just want to give them something that won't be an outlier in Post. If they are already expecting log files then I don't want to give them HG7.
Click to expand...

Probably best to check with the producer (and ideally she'll communicate with the editor/colorist) to see if they are familiar with Sony SGamut3.cine and SLog3. They can certainly get the cameras close by using Rec709 LUTs for both cameras (or making appropriate LUTs for LC709A (Sony) / Wide DR (Canon) as the base grading target) then tuning as needed. Since the FS7 supports custom 3D LUTs, it could save time outputting something closer to Canon. Since it's possible to get good results matching the FS7 to Alexa with LUTs, the same can be done with Canon:

https://www.bertdegraeve.com/single...g3-LUT-to-match-the-Arri-AmiraAlexaAlexa-Mini

Mathematically, if the 3D LUT has a decent sample size and interpolation method, the results will be very high quality (e.g. 33 or greater, tetrahedral/tricubic). I don't see the limits of Cine EI mode to be a big deal, especially for a controlled lighting interview shoot.
 
As it happened the Post team for my producer is very experienced and suggested that Slog3 was fine. I started off assuming that they might not be very savy, which is often a good place to begin. Thanks for all the input though. It will no doubt come in handy in the future.
 
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