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ProRes HQ
In the last week or so, somebody on the Cow wrote that ProRes HQ does not really come into it’s own until your working with 2K files and larger. Is this true? If so then regular Pro Res is just fine for 1080i. I must confess I sometimes don’t see the difference between ProRes and LT.
Don WalkerJohn 3:16
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19 Replies
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[Don Walker] “In the last week or so, somebody on the Cow wrote that ProRes HQ does not really come into it’s own until your working with 2K files and larger. Is this true?”
YES
[Don Walker] “If so then regular Pro Res is just fine for 1080i.”
YES
[Don Walker] “I must confess I sometimes don’t see the difference between ProRes and LT.”
There is a small quality loss, the BIG difference is in the data rate of the files.
There are no “technical solutions” to your “artistic problems”.
Don’t let technology get in the way of your creativity! -
[Don Walker] ” I must confess I sometimes don’t see the difference between ProRes and LT. “
Yes and a H264 at the convenient data rate you may think that is uncompress, but it isn’t .
Hi Don,
I’m of other opinion.
I haven’t see any test or technical paper backing that theory. Apple don’t, of course.
Visually may be no noticeable difference, but you may see it when you further process the picture.
Cheers,
rafael -
Here’s the reason why:
https://forums.creativecow.net/faq/applefinalcutpro#75
Shane
GETTING ORGANIZED WITH FINAL CUT PRO DVD…don’t miss it.
Read my blog, Little Frog in High Def -
Thanks guys for your answers…. especially for pointing out Gary’s little White Paper. Very Informative!
Don WalkerJohn 3:16
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“With the HQ version the CPU is actively interpreting all 256 levels of grey on encode but passing that back out re-interpreted with all 1024 levels on output, that is one HUGE Mathematical Processing task.
With the Standard version of ProRes, that data is not re-interpreted on output until the process actually asks the CPU to handle the content in 10bit by adding filters, efx, or color correction. ”
Although I’ve always stuck with ProRes instead of ProResHQ, it’s only been because that was the point everyone was trying to make – only use HQ when working with 2K or more.
But I never really understood the technical reasoning. I understand that most cameras are just recording 8-bit, but what does Gary mean when he says “re-interpreted for output?” Re-interpreted from what? And what to? When is this re-interpreting taking place?
Thanks!
Robert J. Grauert, Jr.
http://www.robgrauert.com -
[Don Walker] “that ProRes HQ does not really come into it’s own until your working with 2K files and larger. Is this true?”
Can I take a stab at this?
Everyone interrupts my response because the cameras I mention in that note are mainly both considered 2K while it is technically not true, It is still a good guide.
the real reason – it is very hard to get a signal from a vast of cameras that support output signals at 10bits or greater. ( a video tap does not go greater than 10bit)- to get the most out of PRHQ you need to be working with a camera that supports LOG or RGB output over HDSDI /3G / Dual Link.
The real reason that was derived was that converting 8bit materials to HQ is an absolute mistake for the vast majority of users,(IMHO) since the HQ version requires 25%-35% more processing power to playback it would unnecessarily strain playback on your CPU without any gain in quality.
” must confess I sometimes don’t see the difference between ProRes and LT.”
get a bigger display – you can see the difference. I cannot tell on a 17 Panny, but my 32″ cine-tal is a totally different story.
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows for the Digitally Inclined
Chicago, ILhttps://blogs.creativecow.net/24640
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php
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Thanks for chiming I with your thoughts, Gary. I knew your artcile focused more on bit depth rather than pixel count.
And also, with LT there’s a noticeable difference, I agree.
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Ok, So let me see if I’ve got this right:
The purpose of ProRes is to maintain high quality video, but at manageable data rate.
HQ is necessary for 10-bit codecs because they are, well 10-bit and higher quality. The HQ version allows you to maintain that quality, but with a more manageable file.
ProRes is all that’s needed for 8-bit sources because you’re not gaining anything transcoding to 10-bit. It would be like ripping a DVD to DVCPro50 and expecting it to be better than DV25. There is no difference because your original source has already been compressed to less than what you’re transcoding to.
If that is correct, then I’ve got to ask: I thought both ProRes and ProRes HQ were both 10-bit.
Robert J. Grauert, Jr.
http://www.robgrauert.com -
[Rob Grauert] “If that is correct, then I’ve got to ask: I thought both ProRes and ProRes HQ were both 10-bit.”
They are.
Walter Biscardi, Jr.
Editor, Colorist, Director, Writer, Consultant, Author.
HD Post and Production
Biscardi Creative Media“Foul Water, Fiery Serpent” now in Post.
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Apple Final Cut Pro, Apple Motion, Apple Color, AJA Kona, Business & Marketing, Maxx Digital. -
So then that’s it? The only reason to use ProRes instead of HQ is because HQ is giving you a larger data rate with no increase in quality?
Robert J. Grauert, Jr.
http://www.robgrauert.com
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