Highlight the region and shift+b or for a more permanent cache, shift+m works well for transitions. Other programs do this in the background.

In panasonic GH5 II or Gh6 is the most suitable format today. There is nothing better and more popular. It's not 8K. It's standard 4K. I'm shocked Vegas can't do that. 

Unfortunately, the HEVC playback tends to be not strong on Vegas. And the additional issue is, that you shoot to 10bit, and use only 8bit project settings.

Either you can shoot to AVC in your GH5/6, what should be possible. Or you edit your footage with a reduced number of fps during the playback. But I do not know, how many fps you achieve, and which preview settings you see during playback.

I would recommend to shoot to AVC. Even, if it may be possible for UHD 25p only (not sure about that).

If it's 4K 50p it has to be HEVC. GH5 II and GH6 have no other option.

But you have the other option to shoot to UHD 25p/30p also with the Gh5, with AVC All-I or AVC long-GOP. I know that for sure, since I have the same Situation on my EVA1.

If you do not like that, what is fair enough, you can only reduce the preview quality at the moment. I do not know how that may be with the upcoming Vegas Pro 21, what was announced in some advertisings as I have seen.

For 4K50 AVC appears to be an option:

https://eww.pavc.panasonic.co.jp/dscoi/DC-GH6/html/DC-GH6_DVQP2441_eng/0036.html

Panasonic posted a blog recommending ProRes (your camera does 4K 25p internally; save 50p for slow motion):

The great thing about ProRes is that it allows us to record in the best settings our camera offers and presents the footage so that clips play smoothly in our editing software. While you might think that the much larger file sizes would make life more difficult for your computer, it actually has to do much less work decoding them so the footage plays easily. This means we can record in much higher resolutions without the inconvenience of stuttering playback and having to make proxy versions of our footage.

https://www.panasonic.com/uk/consumer/blog/why-shoot-prores-with-the-lumix-gh6.html

ProRes is recommended always, it plays back faster and is also higher quality. If you can do that, I would. If not, it would be worth investing in an Atomos external monitor/recorder that does record to ProRes.

For 4K50 AVC appears to be an option:

https://eww.pavc.panasonic.co.jp/dscoi/DC-GH6/html/DC-GH6_DVQP2441_eng/0036.html

ProRes would be a nice format for editing, but as Frosty said: that seems to require an external recorder.

But the AVC 4K 50p options mentioned by Roger - some of them should work internally too. Why not use them?

@Lukasz-Pecak said:

"In Panasonic GH5 II or Gh6 is the most suitable format today. There is nothing better and more popular. It's not 8K. It's standard 4K."

I just happen to have some GH6 media in my library and it is not a problem for the machine in my signature.

@john_dennis GPU decode doesn't work on my computer, I suspect it doesn't work on any Nvidia or AMD GPU.

Can GH5/GH6 users comment?

This is GH6 6K on a 4K timeline

@Former user

what type of footage is it? And why do you run it with best/full?

@Wolfgang S. It is GH6 6K HEVC 10bit

The quality/resolution doesn't matter when Vegas expects the GPU decoder to work. You can tell by the CPU load. I do get high CPU load when turning GPU decoder off, but it's still only 1-2 fps at Best quality. It would do much better at preview/auto, I didn't test that

Ok. So still 6K HEVC.

But the resolution and quality of the preview always matters. And without hardware specs it is always hard to say much.

So the next question is, if you have an i-GPU support in your system or not. What works better for HEVC then the GPU. But HEVC is still an issue, you are right here.

@Wolfgang S. In the sense of using GH6 6K on a 4K timeline the preview quality/resolution doesn't matter because in this situation Vegas is not using the GPU decoder as it expect to be compounded with the problem of only using a single CPU core to decode. If you use Legacy HEVC decoder the CPU decoding then becomes multicore. This is an old problem I almost had forgot about.

I don't have an IGPU, Ryzen 5900x CPU, 40 series Nvidia GPU

I have here some UHD 50p 10bit footage from my EVA1.

It is possible to have a playback of 50p, if you utilize an i-GPU what is able to support the HEVC 10bit 420 decoding, and if you set the preview to preview half.

And what you see, is that the processor is utilized with 30% only, but that the trick is that HEVC is decoded by the i-GPU (here my Iris).

So, if you do not have an i-GPU, then this may not show an appropriate decoding support for HEVC. Not sure how it would perform on my Rycen system - I use the laptop here. HEVC is not easy.

But for sure, this is no 6K footage (I think my EVA1 is capable to shoot to HEVC in UHD resolution only).

And here the other settings that have an impact to the playback behavior above:

and the footage

ProRes is recommended always, it plays back faster and is also higher quality. If you can do that, I would. If not, it would be worth investing in an Atomos external monitor/recorder that does record to ProRes.

Or they can work on their video engine so that it can perform comparably to other NLEs on the market. It is possible, but they may have to drop things and work exclusively on getting that done given the size of the development team.

IMO, VP20 doesn't feel any different than 16 or 18. I can still only go to Preview (Full) with 1080p60 footage before it starts dropping frames, and that's with GPU Decode and no FX. 4K even with ProRes is not a good editing experience for the type of video content I produce.

I can literally turn off the GPU Decode in Resolve and it will play this footage back with Resolve FX at Full Quality without a frame drop - with just the CPU.

Even at Preview (Full), I sometimes have to loop the clip 3-4x on the timeline to get rid of Stutters and Dropped Frames.

If the Video Engine is inefficient, then it doesn't matter what type of footage you use. You are doing nothing but working around the inefficiency,. You are still limited by the video engine. GPU Decode can only do so much. The engine itself also has to perform.

The higher up in raster you go, the more you decrease the performance headroom. So, 4K 50-60FPS with ProRes on the CPU basically runs into much of the same issues as 1080p60 with the GPU Decoder, because the bottleneck is the VEGAS video engine itself - not the end-user hardware. All switching to ProRes does is kick the can down the road, and it's likely to pop up once you start using any type of processes on that video. That's assuming ProRes 422, cause ProRes HQ/XQ... well, that can also expose some CPU and I/O bottlenecks as well.

Meanwhile, other NLEs will just keep chugging along without issue.

IMO, they probably can benefit on bug fixing VP20 and working predominantly on a new version with an updated Video Engine. It's the biggest issue with the software - the thing that is almost immediately noticed by people who try the software. We can all debate each other's anecdotes, but I don't think I have ever not gotten feedback on this issue from anyone that I've suggested try the software out.

 

So, if you do not have an i-GPU, then this may not show an appropriate decoding support for HEVC. Not sure how it would perform on my Rycen system - I use the laptop here. HEVC is not easy.

@Wolfgang S. Yeah but you're confusing things a little. You're showing me 422 10bit video that my GPU can't decode at all and expounding upon the virtues of modern iris IGPU's decoders over AMD/Nvidia, but modern Nvidia/AMD GPU's can decode 10bit HEVC 420 which is why I show you capcut working fine. It is Vegas that can't GPU decode the GH6 420 file in Vegas

I don't think you need to put a positive spin on every Vegas negative. You should be supportive of improving Vegas for everyone. 13 series Intels are space heaters, but 14 series it is sounding like they may win back the efficiency crown and that's when I"ll buy Intel.

I think there's wide agreement that the VEGAS video engine is the bottleneck and needs an overhaul. We've all had that discussion more than once.

It's just a question of when it can happen. Here's hoping the announcements from Magix about a consolidation and focus on their key product lines (including VEGAS) will mean more resources to develop the program.