How much bitrate do I actually need?

[Amazeballs]

I am gonna come out and confess to everyone.. I shoot everything with a XAVC-HS (which is basicly H265) in 4k24fps at 50mbps on my A7S3. Add 10 bit 422 as well. Yeah, I sad it 🤭

I dont feel like my image is breaking apart or anything and I like that my files are small and compact and my ssds dont bloat as they used to be. Now recently as I noticed that ssd & uhs cards pprices have started coming down, I begin to wounder if I should maybe jump to at least 100 mbps? What do you guys think? I dont shoot for Netflix or any fancy productions and just publish on youtube. Do I really need to bother with at least doubling my bitrate? 

[webrunner5]

I you are happy I am happy. 🤐 But I agree with you, for the average person on here less is better in the long run. If you are not doing heavy grading why shoot 400mb/s. Hell, I was looking through some of my older stuff because one of my drives was getting full and Jesus, I had like 30 OG BMPCC Raw DNG projects on there. It was taking like a 1/4 of the damn drive up. And don't even ask about the Canon 1DC files. 😬

People that want the Sigma FP need their head examined if they want to shoot Raw out of it. Grab your ass on storage space.

I don't even need to turn the heat on in the room where my box computer is, it does all the heat I need!

[KnightsFan]

52 minutes ago, webrunner5 said:

I you are happy I am happy.

This. Do your own tests and trust your judgement, but here's my opinion.

 

If all you care about is how it looks on YouTube, 50 is perfectly fine. No one can tell the difference between a 50 and 100 source file on a 7" phone screen, or a 65" 4k screen 12' away with window glare across the front. I care more about how my content looks in Resolve than on YouTube. And even then, I use 100 mbps H265 (IPB). When I had an XT3, I shot a few full projects at 200 mbps and didn't see any improvement. I've done tests with my Z Cam and can't see benefits to >100. I'd be happy with 50 in most scenarios. It might be confirmation bias but I think I have been in scenarios where 100 looked better than 50, in particular when handheld.

Keep in my also, on most cameras, especially consumer cameras, the nominal rate is the upper limit (it would be a BIG problem the encoder went OVER its nominal rate because the SD card requirements would be a lie). So while I shoot at 100, the file size is usually closer to 70, so it might not even be as big a file size increase as you think. But for me, 100 mpbs is the sweet spot, when shooting H265 IPB.

[PannySVHS]

It also depends on the specific flavour of codec, not only related to bitrate but its "magic" as well. The S1 without the VLog and 10bit 422 update it had a h265 10bit 420 codec in HLG and with 75 Mbit. It had definate flaws in homogenously coloured surfaces such as painted blue wall fi. In these areas the material was full of artefacts, specifically cluster of blocks, which were easily revealed by a strong contrast curve. The 4K 150mbit h264 422 10bit codec, as well as the 100mbit 10bit 422 HD flavour are pretty much seemingly unbreakable. I assume one could film a valid cinema project with it. The 4K8bit 100mbit codec was not shabby at all neither for its proposed use in 709, though paling in comparision to its fantastic 10bit counterpart. The 4K 8bit 100mbit flavour on a Sony A7S2 on the other hand sucks pretty much for more elevated grading needs, even in comparison to a tiny GX85. GX85 flavour of 4K 8bit 100mbit is no slouch if not overwhelming it with the task of serious low light, like above 800Iso under Golden Hour fi. Then mushiness will sneak in, also with noise reduction set all way down to -5. cheers

[newfoundmass]

Like with everything, there's diminishing returns. If you're not doing a ton of tweaking in post, you really don't need huge files, especially if it's only going on YouTube. For a lot of my work 50mbps (or 100mbps in h.264) is more than enough, given the final edit will end up on a streaming service that will stream it at maybe 1/4 of that. 

That's not an argument against higher bit rate options, as there absolutely are plenty of good reasons to have that as an option, but not everything needs to have 400mbps just as not everything needs to be filmed in RAW.

[PannySVHS]

Like I said the 150mbit 422 10bit on the S series and the GH5 is an anwesome codec. Highly recommended even for feature work I must say. Talking about acquisition of course, but that should of course be clear, if talking about codecs in cameras.:)

[kye]

Use however much you need, but be aware that how much you need can vary radically depending on what you're filming.

50Mbps is tonnes if you're filming a talking-head with a blurry background, but point you camera at a tree while there's lots of wind, or during rain or snow, or at the ocean, or from a moving vehicle, and the 50Mbps you were loving before might make you cry.

Also, if you're filming in higher frame rates and then conforming to normal speed to make things appear in slow motion then your bitrate will get stretched accordingly.  50Mbps is 25Mbps when viewed at 50% speed on a timeline, etc.

You can't add bitrate in post!

[MrSMW]

6 minutes ago, kye said:

Also, if you're filming in higher frame rates and then conforming to normal speed to make things appear in slow motion then your bitrate will get stretched accordingly.  50Mbps is 25Mbps when viewed at 50% speed on a timeline, etc.

Good point.

My Panny's are all 150Mbps 420 10 bit and my grade is fairly mild but a lot of 50% Slow mo.

I tried very briefly (once) jumping up to the 400Mbps option...but never again. I didn't see any benefit and it chewed through cards at a crazy rate.

150 therefore is Goldilocks for me.

[newfoundmass]

On 7/17/2022 at 9:32 AM, kye said:

Use however much you need, but be aware that how much you need can vary radically depending on what you're filming.

50Mbps is tonnes if you're filming a talking-head with a blurry background, but point you camera at a tree while there's lots of wind, or during rain or snow, or at the ocean, or from a moving vehicle, and the 50Mbps you were loving before might make you cry.

Also, if you're filming in higher frame rates and then conforming to normal speed to make things appear in slow motion then your bitrate will get stretched accordingly.  50Mbps is 25Mbps when viewed at 50% speed on a timeline, etc.

You can't add bitrate in post!

A lot of that depends on resolution and camera though too. Like the C100 always impressed me with its imagine given it was only what, 24mbps? On the GH5 I could probably find a scenario where I could break it, but I've never had any problems when filming 100mbps in 4K, which would be about 50mbps in h.265 like the OP is using. The only time these days that I really notice mushy or blocky video is when given footage from action cameras and some phones to edit. 

[kye]

30 minutes ago, newfoundmass said:

A lot of that depends on resolution and camera though too. Like the C100 always impressed me with its imagine given it was only what, 24mbps? On the GH5 I could probably find a scenario where I could break it, but I've never had any problems when filming 100mbps in 4K, which would be about 50mbps in h.265 like the OP is using. The only time these days that I really notice mushy or blocky video is when given footage from action cameras and some phones to edit. 

It does depend on how good the compression algorithms are in the camera, but remember that action cameras and smartphones tend to be hand-held (increasing movement in the frame) and wider angle with deep depth of field (so all of the frame has loads of detail to compress) as well as high-res/low-bitrate.

[EduPortas]

I can only speak from a very limited experience but my tiny Nikon Z50 produces beautiful 4K 24p files at 144mbps. I've spent an absurd amount of time admiring the beauty of the files on my 27-inch iMac monitor.

This represents a HUGE step up from the 1080p files coming out of my 7DM2, which has fantastic AF in video but produces very soft output that looks decent on YouTube but never really convinced me when editing on FCX.

Those Nikon files are simply astounding, though, and the Z50 (and Zfc and Z30, I would presume) has very good video AF as well. Shame it has no headphone input :[