"Maximum Render Quality" Better to turn it OFF when using CUDA MPE?

[HungryBudda]

http://crookedpathfilms.com/blog/201...port-settings/

"IMPORTANT NOTE ABOUT RENDERING TIME:  Make sure you do not select “Use  Maximum Render Quality” if you are utilizing the accelerated GPU  graphics (Mercury Playback Engine).  This will not improve your video  and will only slow down the rendering speed by as much as 4 times!"

http://blogs.adobe.com/premiereprotr...e-pro-cs5.html

"For export, scaling with CUDA is always at maximum quality, regardless  of quality settings. (This only applies to scaling done on the GPU.)  Maximum Render Quality can still make a difference with CUDA-accelerated  exports for any parts of the render that are processed on the CPU...

When rendering is done on the CPU with Maximum Render Quality enabled,  processing is done in a linear color space (i.e., gamma = 1.0) at 32  bits per channel (bpc), which results in more realistic results, finer  gradations in color, and better results for midtones. CUDA-accelerated  processing is always performed in a 32-bpc linear color space. To have  results match between CPU rendering and GPU rendering, enable Maximum  Render Quality."

--------------------------------------------------------------------------
Here is what I got out of after reading those two sites:

I should turn it off for it's always ON (when CUDA MPE is used)  regardless I check or uncheck it.Turning it ON only offloads the  calculation to CPU (instead of GPU) hence slowing down the previewing  and encoding performance.
So I guess I should have Maximum Render Quality setting turned OFF in both of squence settings and export settings.
--------------------------------------------------------------------------

However, David Knarr of Studio 1 Productions suggest otherwise:

http://www.studio1productions.com/Articles/PremiereCS5.htm

"When you startup Adobe Premiere CS5 and you don't have a certified video card  (or one that is unlocked) the Mercury Playback Engine is in software rendering mode  and by default the Maximum Render Quality mode (or MRQ) is to OFF.

(Maximum Render Quality mode will maximize the quality of motion in rendered clips and  sequences.  So when you select this option, the video will often  render moving objects more sharply.  Maximum Render Quality also maintains sharp  detail when scaling from large formats to smaller formats, or from  high-definition to standard-definition formats.  For the highest quality exports you should always use the Maximum Render Quality  mode.)

When you unlock Adobe Premiere CS5 so the Mercury Playback Engine can use almost  any newer NVidia card (or if you are using a "certified" NVidia graphics card),  the Mercury Playback Engine will be in the hardware  rendering mode and the Maximum Render Quality mode  will be turned ON.

Since the software mode is not set to maximum render quality,  it can sometime render faster than the hardware render, but a a loss in  qualitly. If you set the software to  maximum render quality you will see that it is very, very slow compared to the  hardware render.

Here is how to set the Maximum Render Quality.
1)  Open up Premiere CS5
2)  Click on Sequence at the top of the screen
3)  Then select Sequence Settings
4)  At the bottom of the window select Maximum Render Quality and click Okay

It is always best to be using the Maximum Render Quality mode,"

--------------------------------------------------------------------------------

Now, I'm lost.

[Harm_Millaard · Accepted solution]

In Todd's blog, this is the crux:

For export, scaling with CUDA is always at maximum quality, regardless of quality settings. (This only applies to scaling done on the GPU.) Maximum Render Quality can still make a difference with CUDA-accelerated exports for any parts of the render that are processed on the CPU. Over time, we are working on reducing the list of exceptions to what can be processed on the GPU. For an example of a limitation that can cause some rendering to fall back to the CPU, see this article: “Maxium dimensions in Premiere Pro CS5″.

So it dpends on your time-line and the effects/transitions used how much of the rendering is done by the CPU instead of the GPU. As soon as the CPU is involved, MRQ helps improve the final quality. To check whether that is the case, export a small but complex piece of your time-line once with and once without MRQ and if it takes about the same time, you can be pretty certain that your time-line will not profit from the MRQ on-setting. If there is a difference in render times, your CPU is involved and you will profit from MRQ.

The statement from Studio1Productions:

When you unlock Adobe Premiere CS5 so the Mercury Playback Engine can use almost  any newer NVidia card (or if you are using a "certified" NVidia graphics card),  the Mercury Playback Engine will be in the hardware  rendering mode and the Maximum Render Quality mode  will be turned ON.

is incorrect, because MRQ can be ON or OFF with hardware MPE. There is a difference between "Maximum Quality" that is always used for scaling and "Maximum Render Quality" that can be used for CPU bound renders.

[Todd_Kopriva]

Harm is right.

[RDA972]

The above statement is bound to warm the cockles of Harm's heart.

Although his name suggests otherwise, he is a force for good rather than ill.

[thxapproved]

After reading much of the information online and here in this forum, and having my own questions about the curious little checkbox, I've only one major question now...
Why is this thing such a curious box with no clear documentation as to the fullness of its implications and actions?  If it were crystal clear, there would have been less confustion, one would assume (then again, we know what happens when one assumes).

[HungryBudda]

Thank you so much for the answer but I'm not sure if I'm getting it 100% right.

Below is how I understood your answer:

CUDA MPE always runs in highest quality mode regardless of MRQ setting; however, there're some effects/transitions that CUDA MPE can't help. In that case, CPU is solely responsible of rendering such effects/transitions and that having MRQ off results in poorer quality.

In other words, if I want to achieve highest possible quality, I should have MRQ on so that CPU can do the high quality oriented processing. However, if I'm certain that all the  effects/transitions are handled by CUDA MPE, turning MRQ on or off does not make a difference in terms of speed and quality.

Can you let me know if what I wrote above is correct?

[Harm_Millaard]

That is a fine summary.

[Dave_Knarr]

I think there is some confusion to what I am saying in the article where it says:

"

When you unlock Adobe Premiere CS5 so the Mercury Playback Engine can use almost  any newer NVidia card (or if you are using a "certified" NVidia graphics card),  the Mercury Playback Engine will be in the hardware  rendering mode and the Maximum Render Quality mode  will be turned ON."

What I am talking about is when you first enable the hardware rendering mode the Maximum Render Quailty mode is automatically set to ON by Premiere CS5.  At least that is how it worked on my systems.

  That part of the article is talking about how in the Software Rendering mode it is off by default and on when you first turn hardware rendering mode on.

I am not saying that you can't turn it off, which of course you can.  I will update the article tonight to make it even clearer for everyone.

I have found that setting the Maximum Render Quality set to on produced a better preview and exported video with the footage and effect that I was using.

Cheers

David Knarr

Studio 1 Productions

[Colin_Brougham]

What I am talking about is when you first enable the hardware rendering mode the Maximum Render Quailty mode is automatically set to ON by Premiere CS5.  At least that is how it worked on my systems.

I don't believe that to be the case at all. Turning on hardware acceleration is a project-level setting (that seems to trickle from project to project, after it has been turned on), whereas Maximum Render Quality (the checkbox) is a sequence setting that is not automatically set, ever. I don't believe there is a connection, intrinsic or inherited, between the two.

Unless you're not talking about MRQ (the checkbox), but rather the enhanced rendering capability of hardware MPE...

[Dave_Knarr]

Okay, I am loosing it.....    You are correct.

I am not sure what I was remembering, I could have sworn that when I loaded Premiere CS5 for the first time before I unlocked the video card, the Maximum Render Quality mode was NOT checked.  Then when I unlocked the video card,  the Maximum Render Quality mode was check to ON and I didn't set it to be On.

I just when back and uninstalled Premiere and re-installed it, to see what was going on and I was totally wrong.

Sorry for the mistake and I will be updating the article on my website in the next 15 min.

Also, I have written a small program to do the unlock automatically.  The program is free and it works with the cards listed under the Automatic Mode.

If your video card isn't listen, just let me know what your card is and what you typed into the cuda cards file and I will add it to the program.

David Knarr

Studio 1 Productions

[Colin_Brougham]

I just when back and uninstalled Premiere and re-installed it, to see what was going on and I was totally wrong.

That seems a bit extreme for such a minor point

Anyway, my goal wasn't really to call you out on it; just didn't want anyone else to think that something wasn't happening when it should be (when it really won't). Or, something like that.

It's all good

[Dave_Knarr]

Hi Colin,

It's wasn't extreme for me. 

I just wanted to make sure my notes were correct and what I remembered was correct.

I thank you and Harm for pointing out the correction to me.  I just want to make sure the article contains correct info.

Cheers

Dave