ProRes 422 or 422HQ?

[Brontosaurus]

I have read that ProRes 422HQ supports 10-bit, and ProRes 422 supports 8-bit. If the camera output is 8-bit is there any advantage in using 422HQ over 422?  I'm not thinking here about the degredation due to processing in the edit and multiple encoding/decoding, but only the visual quality of the original recording.

[Steve Griffiths]

All Prores formats support 10 bit. So it really comes down to if you think the extra file size of ProresHQ is worth it if you are recording camera 8 bit files. The answer? If you want maximum quality then go ProresHQ. ProresHQ will apply less compression to your source camera files ... and this is regardless of them being 8 or 10 bit images.

However standard Prores422 is (IMO) still pretty good and may be fine for your needs.

You mention "multiple encoding/decoding" - is that likely to happen? Are you actually going to be doing multiple outputs and then re-edits of your projects? 

If I'm shooting long form conference material I'll even go down to ProresLT to save space - it's remarkably OK when file size is an issue and still provides good results. But for my own projects I use Prores422. In a broadcast environment we use ProresHQ.

[Brontosaurus]

I won't really be doing multiple encoding/decoding, but occasionaly complex processing such as blue screening. I presume the definition won't be worse in 422 than in HQ? What sort of unwanted effects might you get in 422 that you don't get in HQ? Also if I have footage shot in H.264 which I want to convert to ProRes to do effects on, will HQ be better quality than 422 for this H.264 footage?

[Steve Griffiths]

I started writing a post about color space 422 vs 444 but that too complicated for here and hurts my brain 🙂

If you want to know more online search '422 v 444 color space' for some (complex) reading material.

ProresHQ and Prores 422 both use 422 color space and this does introduce issues when keying blue/green screen.

But not something you can solve unless your camera outputs 444 AND you can record it in (say) Prores4444.

In regards to your question regarding definition between HQ & 422. No loss of definition - just more compression and if you are keying I'd go with HQ. Extra compression can affect the quality of your keys.

You could convert your h.264 to Prores, and lot's people do, but it's not absolutely necessary. The benefits in doing this are more to do with taking the load off Premiere Pro while editing (smoother, less laggy performance). Converting H.264 to Prores will not in anyway make for better quality effects processing or improvement in picture quality. But if you are going to do it, then yes, go with HQ