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EOSHD LOG Converter for the GH4


Andrew Reid
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I´d really like to see some examples from users! Not trying to bitch or anything, but this sounds a bit too good/easy for the gain...If you get "all the gains" from a real LOG profile, what would you need one for and why does it take huge companies long to make LOG profiles etc. etc.

 

I think this is really interesting but will hold off until I see some results from other people than the author ;)

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I can't see how this would be of benefit? You're not gaining any data as the conversion to a log space happens after the camera processing and compression. It looks flat, but you're not gaining any information..so other than easier matching to LOG from a C series, what's the point (or is that the point?).

Most LUTs don't support Rec709, so converting into LOG "flatness" gives you access to wider variety of LUTs (like DeLuts or Arri Alexa profiles in FilmConvert).

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Nice, but can you explain the difference between capturing in camera using the flat picture profile from your gh4 user guide compared to capturing with the cinema picture profile and converting to log in post?

The difference:

The in-camera picture profile is extremely basic and not designed to deliver results compatible with professional colour grading methods. It has a few sliders - contrast, saturation, tone, that is about it. Resolve it isn't!!

A LUT applied to the image in post is much more advanced than the Photo Style. This is a 3D matrix of a huge amount of numbers. Look at the complexity of DaVinci Resolve's entire user interface and compact it into a LUT file.

As Hene1 pointed out above, the Rec.709 image out of the GH4 is not LOG and needs to be made compatible with this 3D LUT for you to benefit from that kind of control over colour and mood.

If you dial contrast all the way down and try to make it too flat in-camera it looks terrible. Contrast -5 is a big no-no because it kills tonality, skin tones and colour.

It is better to use the optimised EOSHD Cinema settings for this and keep as much colour information as possible, then the LOG conversion uses a very sophisticated 3D LUT to convert the file into a gamma curve and overall Canon-LOG style profile that is compatible with the final Output LUT.

The final output LUT is whatever you want it to be. It could be one of James Miller's excellent DELUTS for example, or you can use the beautiful 1D C LUT which I included with the download. That really does wonders for warmer skin, healthier looking actors, no more weird yellow casts, and highlights look more cinematic, colours have more impact, it overall looks more stylistic than without.

It sounds complicated but in practice it is easy, as the guide that comes with the files will show you. Aside from the advantage of basically being able to choose your "Photo Style" in post (rather than being stuck with the crappy ones in-camera) from a range of thousands and share your own "styles" online, you really are getting a drastically more cinematic image out of the camera by using this workflow.

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Most LUTs don't support Rec709, so converting into LOG "flatness" gives you access to wider variety of LUTs (like DeLuts or Arri Alexa profiles in FilmConvert).

Every single LUT that I own supports Rec709 except the input LUTs with Lumetri in Premiere. Those are just for converting LOG to a Rec709 color space.

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Every single LUT that I own supports Rec709 except the input LUTs with Lumetri in Premiere. Those are just for converting LOG to a Rec709 color space.

No, most LUTs out there are meant to be used with LOG. If you're applying the final Output LUTs to Rec709 you have to bend the image further to where the LUT wants to take it. Often Rec 709 will have crushed blacks and the LUT would create a flat grey out of this without the nice variation in luminosity you get from the blacks with LOG.

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Sweet, makes sense now. Cheers for your insights. Will be interesting to see V-LOG with your 1D C LUT.

The difference:

The in-camera picture profile is extremely basic and not designed to deliver results compatible with professional colour grading methods. It has a few sliders - contrast, saturation, tone, that is about it. Resolve it isn't!!

A LUT applied to the image in post is much more advanced than the Photo Style. This is a 3D matrix of a huge amount of numbers. Look at the complexity of DaVinci Resolve's entire user interface and compact it into a LUT file.

As Hene1 pointed out above, the Rec.709 image out of the GH4 is not LOG and needs to be made compatible with this 3D LUT for you to benefit from that kind of control over colour and mood.

If you dial contrast all the way down and try to make it too flat in-camera it looks terrible. Contrast -5 is a big no-no because it kills tonality, skin tones and colour.

It is better to use the optimised EOSHD Cinema settings for this and keep as much colour information as possible, then the LOG conversion uses a very sophisticated 3D LUT to convert the file into a gamma curve and overall Canon-LOG style profile that is compatible with the final Output LUT.

The final output LUT is whatever you want it to be. It could be one of James Miller's excellent DELUTS for example, or you can use the beautiful 1D C LUT which I included with the download. That really does wonders for warmer skin, healthier looking actors, no more weird yellow casts, and highlights look more cinematic, colours have more impact, it overall looks more stylistic than without.

It sounds complicated but in practice it is easy, as the guide that comes with the files will show you. Aside from the advantage of basically being able to choose your "Photo Style" in post (rather than being stuck with the crappy ones in-camera) from a range of thousands and share your own "styles" online, you really are getting a drastically more cinematic image out of the camera by using this workflow.

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No, most LUTs out there are meant to be used with LOG. If you're applying the final Output LUTs to Rec709 you have to bend the image further to where the LUT wants to take it. Often Rec 709 will have crushed blacks and the LUT would create a flat grey out of this without the nice variation in luminosity you get from the blacks with LOG.

but in the case of GH4 you are bending twice. Once to flatten into LOG, then again back to a final graded look. What I'm saying is if the Natural/Portrait looks can retain enough info in highs/shadows to create a LOG image, then why not just make the tweaks in a Rec 709 LUT, and skip the middle process. 

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Also you can apply the LOG LUT in the transcode, then you get the LOG ProRes as if it has come straight from the camera as LOG.

I prefer to edit ProRes to H.264. 4K bogs down too much in H.264 on my Macbook Pro.

What would be the workflow for this? Is there a way to do it in media encoder or would you have to use resolve?

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No only the GH4 actually

The G7 doesn't have the advanced in-camera picture controls to make it suitable for the LOG Converter.

Andrew,

any chance that GM1/GX7/G7 might benefit from this as well? I understand that this profile depends on GH4 settings that are unique, but maybe there is some way arround...? i would gladly accept some sacrifices :)

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but in the case of GH4 you are bending twice. Once to flatten into LOG, then again back to a final graded look. What I'm saying is if the Natural/Portrait looks can retain enough info in highs/shadows to create a LOG image, then why not just make the tweaks in a Rec 709 LUT, and skip the middle process. 

Why not make the tweaks in a rec 709 LUT? As I have already said, most LUTs and almost all the pro camera ones are designed for LOG, be it Canon LOG, S-LOG, Arri LOG (LOG-C), etc. My LOG conversion workflow is designed to make the GH4 which cannot record LOG compatible with those. If you want to carry on using a Rec 709 LUT nobody is stopping you. I don't see why you need to keep justifying your own choice over the top of mine, distracting everyone from the topic.

LOG in-camera is designed to capture more highlight information, so it is not just a grading assist.

However because you can underexpose with my workflow, as the blacks aren't as crushed, you do protect the highlights more and also bring a ton of tonality in the highs down into the sweet spot, rather than really close to the clipping point where they look terrible, colour wise.

Here is some good reading from Arri:

http://www.arri.com/camera/alexa/learn/log_c_and_rec_709_video/

As people have been using this thread to critique the LOG Converter without even trying it first I've had to clean it up. Please stay on topic. I am using this workflow myself. If it didn't do what I claimed I wouldn't be using it. Go figure.

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Why not make the tweaks in a rec 709 LUT? As I have already said, most LUTs and almost all the pro camera ones are designed for LOG, be it Canon LOG, S-LOG, Arri LOG (LOG-C), etc. My LOG conversion workflow is designed to make the GH4 which cannot record LOG compatible with those. If you want to carry on using a Rec 709 LUT nobody is stopping you. I don't see why you need to keep justifying your own choice over the top of mine, distracting everyone from the topic.

LOG in-camera is designed to capture more highlight information, so it is not just a grading assist.

However because you can underexpose with my workflow, as the blacks aren't as crushed, you do protect the highlights more and also bring a ton of tonality in the highs down into the sweet spot, rather than really close to the clipping point where they look terrible, colour wise.

Here is some good reading from Arri:

http://www.arri.com/camera/alexa/learn/log_c_and_rec_709_video/

As people have been using this thread to critique the LOG Converter without even trying it first I've had to clean it up. Please stay on topic. I am using this workflow myself. If it didn't do what I claimed I wouldn't be using it. Go figure.

That makes sense. I was just under the impression you were wanting to only correct the bad color shifts (yellows, reds). 

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Hi Guys,

 

I have tested the LUTs and I think they are great and I will definitely be using this for an upcoming travel shoot.  I recently shot with the 1dc and GH4 as B cam for an interview and even though at the time (a few weeks ago) I was using a different profile setup I just tried throwing the input and output LUTs on to it to see what would happen and it was great. Surprised how close it came to the 1dc.  Just a few minor tweaks and they intercut amazingly well.  

I tried the EOSHD recommended profile setup as well as the Naomkroll LUT and also a third variation where I changed the EOSHD recommended from Cine V to Cine D keeping everything the same.  I felt the Cine D variation had more detail in the shadows although it was a lot noisier than the recommended profile which was silky smooth in my blacks.  But after I ran NeatVideo the noise was gone and the picture had a bit more detail in the blacks which I prefer.  This is all just my opinion.  Be interesting to hear how other people are getting on.  Now I want to try it with Supertone profile setup, I wonder how that will work out. 

 

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I didn't have any Cine V footage at hand, but here is Portrait > EOSHD LOG converter > Kodak Elite Chrome LOG LUT

Very nice Aaron. And thanks for your support with the purchase.

Nice that people are experimenting with different in-camera profiles before taking it to the EOSHD LOG Converter.

I tried the EOSHD recommended profile setup as well as the Naomkroll LUT and also a third variation where I changed the EOSHD recommended from Cine V to Cine D keeping everything the same.

Curious to see the results of that as well!

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I don't have any CineV either. I believe this was shot in the Natural profile. I'm going to try your profile in the next few days because when I apply the 1D-C LUT everything looks pretty magenta. With that said, this image is with EOSHD LOG Converter to Kodak Vision 5213. Very minor adjustments from there, as it's bed time :-)

 

Screen Shot 2015-08-16 at 11.03.20 PM.png

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