Enabling LOG C color space conversion with cLog or sLOG footage.

Log-c and other log color spaces are very similar. That is the whole point of using them. They have very similar tonal attributes which makes it easy to match shots from different cameras. The advantage is to gain an s-curve within Final Cut Pro x natively, which is otherwise only possible with a 3rd party plugin. I need an s-curve to manage soft highlights since the gain control tends to clip footage without a highlight compression option.

Thanks for the reply BenB. I appreciate your willingness to help with this topic, but I'm not sure you understand what I want to do and why.

I want to use the LUT for its Luma curve in actual color corrections in FCP-X. I am not trying to use it for display of dailies or other uses which are common with LUTs.

LOG space color space is similar, but not identical with many cameras. ARRI LOG-C is also very similar to the color space used in Cineon and DPX film scans which I used to see regularly. The black points may vary, but I can adjust black points in many ways. The general shape of the LUT curve should be very similar to other curves used to correct other LOG spaces. If these curves were dramatically different from eachother, they wouldn't be defined as LOG space. LOG is a mathematical formula for how the bits are arranged and reserved in the file structure which is somewhat similar to how stills photographers manage Zone System exposure indexes There is no magic about the way ARRI defines this. It is a way for ARRI footage to match 35mm scans easily and other cameras using LOG space such as the ones I am using regularly. I would LOVE to have Apple include specific LOG LUT's for each camera which I use, but since they have not done that yet, I would like to experiement with the included one which is designed for ARRI LOG-C.

I am a very experienced professional and understand very well how and why LUT's are being used in many ways across the industry. Yes, I use Resolve for certain tasks and yes, it is the best place to do advanced color work. The new Resolve LOG color correction pane is very useful and superior to all tools I've seen. But I also use and enjoy the convenience of keeping my material within FCP-X as much as possible. And in many cases, FCP-X color correction tools are adequate for my needs. But when using Cinestyle, cLOG or sLOG footage on my cameras, controlling the rolloff of highlights is very difficult to do with the simple 3-way controls. in FCP-X.

Since FCP-X has no Luma or RGB curves tool built-in, I currently use the Nattress Curves plugin in an Adjustment layer over my timelines to provide a basic film look. The downside to this is that not all my editbays have licenses for the 3rd party plugins, and also there are some odd workflow issues which would be much simpler to manage the way that FCP-X does with Arri LOG-C footage.

My question is how to trick FCP-X into thinking the footage is LOG-C so I can use the newly added checkbox to interpret the footage using the LOG-C LUT in an early stage of color correction while the footage is still managed in Floating Point color space.

The LOG-C profile in the Nattress plugin works as a very good starting point for advanced color correction for footage shot by Sony F3, Canon C and Canon Cinestyle cameras. In fact, it is also a fairly good starting point for GoPro Hero3 ProTune footage as well. I am not attempting ot use the LOG-C LUT solely for color correction. Instead, I want to use it for CineGamma tonal correction which is only possible with a proper luma or RGB Curve. I will then use the FCP-X color panes to ad specific modifications to each camera's footage to more closely match what I'm looking for. If I'm dealing with a camera with lower dynamic range, I adjust the FCP-X panes to compensate for that particular camera, then Paste these attributes to all the clips from that camera. This often results in a very good match from camera to camera while using the same LUT for the tonal look. I would like to test this technique using the built-in ARRI LOG-C feature, but unfortunately, cannot until FCP-X allows me to use the LUT on other kinds of footage.

I hope this makes sense. Keep in mind I am a very experienced and technical user and have a long history in the blogosphere and forums about these kinds of topics. I have very specific reasons for why I want to do this, and until Apple provides other LOG correction tools or a bonafide Curves tool, I am seeking to find a way to use the LOG-C as an alternative solution. BenB, it could be that Apple has closed out the LUT from other types of footage because of comments from their close peers which are not exactly helpful to actual real-world users. There are many more cLOG, sLOG and Cinestyle users using FCP-X than there are ARRI users and it is unfortunately they chose to limit their features to exclude these somewhat arbitrarily. My goal is to find a workaround for this odd decision and would love any tips or suggestions if the answer lies in the footage Metadata.

BTW, color spaces is the term I have chosen to use for a reason. I mean them in the way that Still Photos are managed by Color spaces. ProPhoto, Adobe RGB, sRGB are all RGB color spaces. RGB alone is not a color space, it is a color format. The distribution of bits and what they mean relative to terms like Black, White, midpoint, Superwhite, clipping points, etc is the color space. LOG spaces define the number of bits devoted to each stop of an exposure in a different way than traditional linear and video color spaces. Canon LOG is a color space which can be used by various formats. For instance, I can record 420 AVCHD into cLOG on my C100, but I can also record cLOG into a 444 or 422 color format using a 444 recorder. It is not just a camera profile. It is not more a camera specific profile than Adobe RGB or ProPhoto are to stills cameras. It is simply a definition which is useful when performing advanced color corrections. The advantage of accessing the ARRI LOG LUT within FCP-X is to compensate for Apple's glaring omission of a built-in curves function in FCP-X. Nothing more nothing less. All I really want is to access this new feature with all my LOG footage and if you have any tips on how to do this, please advise. Thanks, Matt

Yes. I use Resolve Lite currently for many jobs, but it is a separate app which reads exported XML from FCP-X. Many times I like to color correct clips or grade for a style while editing, rather than afterwards. Keeping most of what I need in the Magnetic Timeline right until the end of a project is one of my main reasons I love Final Cut Pro. Keeping things together and flexible throughout the production is where Final Cut Pro's built-in tools are very useful. But Apple doesn't have a Luma curve or any kind of LOG space controls like we have in Aperture or the latest version of Resolve such as Black, Shadow, Highlights and White, or mid contrast controls. Plus, the Broadcast safe filter which can function as a slight highlight compressor, clips footage before the color corrector can get access the highlight data. Apples's 3-point linear correctors are good but simply not designed to process LOG formated files.

What I want to do is use FCP-X with a LOG curve which is included for Arri footage clips. I know there is a metadata tag in the ARRI footage clips which must tell Final Cut Pro X to enable the feature, and I think I can mimic this in my other LOG clips.

I don't want to debate whether it is a good idea to do this inside Final Cut Pro X vs another app or workflow process. I want to be able to test the idea directly and will report if I have success. The key is to spoof the FCP-X info panel into allowing me to use the LUT.

If I can't do this, I'll simply keep using the Natress Curves as a temporary solution until Apple updates the app to support proper LOG Color spaces in a way that is similar to the way Aperture does.