Andrew - EOSHD

  I already told you several times what I think...   Compression is a factor, as is exposure.   I also said countless times before... 10bit luma is is not the same as having 10bit colour.   I also told you that David Newman of CineForm / GoPro backs up the 8bit 4K -> 10bit 1080p argument as does Thomas Worth of Rarevision. If you can't listen to the experts, I as a non-colour science engineer will have no chance in putting you straight!!

I have a suggestion...   Some of you will have access to 10bit (or better) already. Blackmagic Pocket Cinema Camera, 5D Mark III raw, external HDMI on the GH4 itself.   It is this you need to compare the 8bit 4K to when doing tests for banding.   The banding test on its own is a bit pointless.

It's actually a plugin for forums that makes idiots go away.   Oh... I wish.

  Here's an example from me...   Top shot is 100% crop of the 4K image. You can see some banding. Bottom shot is 100% crop of the 4K down sampled to 1080p. Much smoother looking and crisper.

It looks like mega extreme push or pull, no wonder it is shot to pieces.   Try instead shooting a detailed surface which is unevenly lit, say with a light source at one edge of it, shoot it in 4K then don't touch the image, just convert it to 1080p 10bit ProRes. Only after that, see how it grades compared to the 8bit 1080p files direct from the GH4.

I believe what you're seeing in that frame is not the result of 8bit colour but actually heavy compression.   Bland areas like skies are more heavily compressed than areas with fine detail.   Also remember that colour remains 8bit... it is only the depth of the luma channel and colour sampling which benefit from the downscaling from 4K to 1080p.

  Just change one clip, copy it (CMD-C) highlight all the others on the timeline, right click, Paste Attributes, done.

Perhaps use Resolve to convert DPX to ProRes? That uses the GPU to render, so it's much faster.

Well, breaking the image before you do the downscale and convert to DNxHD is kind of a 'shit in, shit out' situation isn't it?   Try grading it after processing instead!

It isn't an image quality thing...   The different 1080p modes vary in other ways.   ALL-I for instance is easier on your computer to edit. The complex encoding for IPB is not there, just each individual frame 'as-is' one after the other like a sequence of JPEGs.   The bitrate of 200Mbit/s is higher in ALL-I just to maintain image quality, not to improve it from 100Mbit/s in IPB mode.   Because the efficiency of an ALL-I codec is lower, the data rate needs to increase.   So it is a common user misconception that image quality and bitrate have a direct correlation!   Shoot 1080p ALL-I if you need easier to edit files.   Shoot 1080p IPB if you need smaller file sizes and best quality compression.   Shoot 4K and upgrade your laptop if you want to get a clue ;)

As long as it takes to fix.   It isn't in my hands so I'm not really the one to ask.   Let's move along please, as people will use this topic to dig for info and I don't think that's fair on me.

  4x smaller bands = finer gradient.   Simple enough yeah?

  Unfortunately I'm still not allowed to spill the beans.   The announcement is delayed!   Will be worth waiting for though.

Image quality looks identical to the Sony RX10 but the higher bitrate should really help with the heavy breakup and mud I experienced with that camera. Glad to see the back of AVCHD as well.   Curious to see if moire is dealt with better this time too.   Great compact camera... Perhaps the best.   Not a DSLR / mirrorless beater due to sensor size and no interchangeable lenses but for what it is, it seems very good... love the pop up EVF!   Might be good on drones too.

They should consider doing some 4K coverage as well ;)   http://www.bbc.com/news/world-latin-america-27635908

You really think I am referring to the king of dumbness when I say there aren't many great action directors around at the moment... Oh dear.   I meant enthralling... Duncan Jones 'Source Code' was pretty good.

In touch with Sony about a A7S demo unit so wait to see if it turns the world's number 1 GH4 fanboy onto it :)

Is there any chance you can get a GH4 to play with JG and do a comparison with the C100? I'm curious to see how it performs vs that and the Ninja.   I do think the internal codec sacrifices the lows, my work-arounds are just that really... not so much a cure but a technique to try and improve it.   With an external recorder I'm curious to see what the GH4 looks like as well especially the 4K -> 1080p down convert.   I am in touch with Atomos and will be getting some demo units hopefully soon!

Stay constructive Fuzzynormal. That's clear flame bate and adds nothing to the topic at all.

Here's some of my grades with Cinema profile from the guide. Let me know if you want a complimentary copy JG.   Click for the full 4K.   As long as you expose to the right the shadows are silky smooth on the GH4.      

Also depends on the exposure. James Miller has had some nice shadows out of it  

  Yes.

I believe it refers to AFF mode. That has the spatial awareness to detect the direction an object is travelling in and whether the focus point should move forwards or backwards.   Of course if the train is coming towards the camera at 200kph I wouldn't like to be the one to find out if it tracks or not :)

  Try Master Pedestal + 15. That seems to allocate more bitrate to the shadows and stops them from crushing so much.   Then I lift the bottom of my s-curve in Premiere like Kendy Ty does with his T2i.   That gives me rich tonality and colour but with more detail in the blacks.

  Exactly, you're no expert and that's OK... But polluting my forum with misinformation is not.   10bit data from 8bit 4K... just ask Rarevision and CineForm. http://www.eoshd.com/content/12140/discovery-4k-8bit-420-panasonic-gh4-converts-1080p-10bit-444   This is something which applies equally to both the A7S and GH4 but the GH4 does it internally, and steps up to 10bit externally... that's 10bit colour and not just 10bit luma.   It isn't about pixel peeping it's about getting the facts straight!