We're all aware that 4 K converted to 1080p looks great and that the color depth has been increased in the downgrading process. . But when do you color correct? Do you do all your color work on the 4 K footage and then export to 1080P, or do you convert first the 4 K footage to some decent codec such as Prores or Avid and then color correct the 1080p footage? It seems to me that the second option would make more sense since, supposedly, the footage acquired more color depth as it was converted to 2K and it' better to color grade a footage with more information.
So?

I shoot 4K with my G7 only for acquisition. I bring the 4k into a Premiere Pro 1080p timeline and export it as a ProRes file. The 1080p ProRes files are what I edit and grade with. I archive the 4K files.
I do this only because my computer is not beefy enough to adequately handle 4K footage once I start to color correct, add effects etc. I have done some testing to compare 3 different ways.
1) Put a 4K clip in a 4K timeline, color correct, then export as 1080p ProRes.
2) Put a 4K clip in a 1080p timeline, color correct, then export as 1080p ProRes.
3) Put a 4K clip in a 1080p timeline, export as ProRes and bring it back in to color correct, and export again as 1080p ProRes. This method is easiest on my computer.
Looking at the 3 ProRes1080p clips from the 3 methods, I cannot tell the difference between them. So, the 3rd way is easiest for me, and my computer, and does not seem to cause any file degradation that I can see. Perhaps not the most time efficient, but for me it works very well.

I would prefer to edit 1080p than 4k.

I import 4K (it's really UHD) footage into a premiere pro 1080p timeline and do all my editing and lock it in. Only then after having watched the video for errors and confirming that it's good do I start my color correction and color grading. Once I start to add all my effects, my playback is severely hampered, especially when I add noise removal. Once I complete my grade by just looking a single frame of the video clip, I'll mark an in to out point and render that in to out point and preview it just to make sure that my grade didn't introduce any artifacts that creep in during motion (like over sharpening for example). Once I've confirmed that I export for release!

I put in on a 4k timeline to sharpen, colourgrade, stabilize, make zooms and pans and export final program into HD. Best final product!

Thanks all of you for your comments.
So there seems not to have any differences in the way it's graded, before exporting to 1080 or after, grading 4 K or grading the exported 1080. Yes, I can see that.

I put in on a 4k timeline to sharpen, colourgrade, stabilize, make zooms and pans and export final program into HD. Best final product!

Zooming into 4k footage on a 4k timeline results in image quality loss but not if you add 4k footage on a HD timeline.

Wouldn't you have greater degrees of freedom after converting to 1080 via the larger color space?

Jim, that's what I've been trying to have others acknowledged! Since you can color grade better with something in 422 vs 420 it seems to me that you'll have more latitude if you export FIRST to a better color space 1080 and correct versus correcting a 420 4K and then exporting. This is what I have noticed and I wanted others to confirm.

Wouldn't you have greater degrees of freedom after converting to 1080 via the larger color space?


Not in my experience and I have had the GH4 for 2 years no. IMO there is no visible change in color space. I have considerable experience with other cameras shooting in 4:2:2. Now I do notice much more image sharpness converting 4k to 1080 which is how I handle macro shots.

Zooming into 4k footage on a 4k timeline results in image quality loss but not if you add 4k footage on a HD timeline.
I have never had any problem working in a 4k timeline and zoom in the footage - If you end up with a pixel count larger than 1920x1080 you will never see any problem with the footage you end up with. When you put it in a HD timeline - you start degrading your footage to HD and can stay there until you zoom longer into the footage than 1920x1080. I see the best quality when I work in 4k - grafics are also created in 4k solution and you can zoom in too, without degration! When I have finished my project i export to HD. And I make it in 4k too - on a 4k tv you often would not see that you have made the zooms! I zoom mostly about 10% and sometimes 20%.

Sorry but that makes makes no sense, if you edit 4k footage in a 4k project and when you crop the footage you will start to loose detail which is not the case if you edit 4k footage in a 1080p project and then crop/zoom into the footage. I can easily prove that.

Well, I"ll be, just zoomed from 100% to 200% on 4K footage on a 4K timeline and exported as 4K footage and zoomed in from 50% to 100% on 4K footage on a 1080p timeline and exported as a 1080p file so I ended up with the same frame and both look exactly the same! :) I did not see any degrading like you said though in the 1080p project, both files look exactly the same to me. I does still puzzle me why the 4K footage in the 4K project doesn't seem to loose detail when you zoom into the footage, if you do the same on 1080p footage in a 1080p project you clearly will see a degrading in IQ.

If your footage is 4k and you zoom in on a 4 k timeline - yes you will lose finer details. If you start with a HD timeline you will lose detail from the beginning and lose nothing - as long as you do not zoom more than into a frame of 1080x1920 in your original footage.
Bo

Not in my experience and I have had the GH4 for 2 years no. IMO there is no visible change in color space. I have considerable experience with other cameras shooting in 4:2:2.

I agree with Mark. I feel this whole "4:4:4 from 4K 4:2:0 downscaled to 1080" is a load of nonsense. I have a native 10-bit 4:2:2 camera, and I routinely shoot 1080 8-bit 4:2:2 out via a Shogun. On one shoot a while back I forget media for the Shogun, so I just set the camera to 4K and downscaled to 1080 in both Resolve and Media Encoder (utilizing Maximum Image Quality which toggles the high-end scaler). It clearly did not grade like the straight up 4:2:2 Shogun ProRes HQ files do.

Ok, so the myth of the better color space once the footage is downgraded to 1080 has been destroyed.
As far as sharpness, I really don't care increasing the sharpness at all, it's sharp enough. My problem with all those cheap 8 bits cam, I found a G 7 for $450, is not the sharpness but the color space. There is a local access TV station where I live that let us play with a RED Scarlet and I simply can't stand how little latitude I have with the G7. I've actually learned how to love the stills it produces with vintage lenses. I'm playing with some older Nikkors, but for video I've found out that it simply can't even come close to what a Canon XF 305 can do while recording to an outside recorder in 4:2:2, sure the G7 is 4K

If latitude is so important to you and the ability to grade the footage why don't you buy a Black magic camera and shoot raw?

My problem with all those cheap 8 bits cam, I found a G 7 for $450, is not the sharpness but the color space. There is a local access TV station where I live that let us play with a RED Scarlet and I simply can't stand how little latitude I have with the G7.

What are you doing to the footage exactly? Adding saturation? Adjusting contrast?

Larry, now I remember our discussion again from a while ago about the black magic camera's :) In that case just disregard my last suggestion, last thing you said about the G7 was that it had "more then enough quality for you to tell the stories you care about" and now that's not possible anymore because of the colorspace? What did you expect from downgrading 4:2:0 8 bit 4K to 1080p, that it would become gradable like raw footage?

I just got a G7, and it feels like you really have to nail your exposure on camera in 4K 100mbps My best results came from exporting the sequence as tiffs, then importing all the frames into light room. Then I could bring down the highlights and shadows a bit more than effects in premiere. Then re-exported and back to after effects, then exported as a Cineform 10bit video. then adobe media encoder for a youtube version.

Not something to do for just homevideos but if its something worth wild.

Would you not be able to do the same in resolve? I have tried it but looks to complicated to me but it would save doing those roundtrips between different programs.