I often create multi layered effects sequences which I know will need rendering as I progress otherwise they will not play accurately in real time.

Rendering can be time for a cup of coffee, or it can also be a waste of time while you wait. And there's nothing more irritating than waiting 10 minutes for a render job to complete, only to find that one of your cuts or effects settings was wrong and you have to do it again - and wait again.

My old editing system FAST Liquid Silver (frok 1998 and which ran on a much less powerful platform) had a nice feature - you could enable a small preview window together with the rendering progress bar so you could follow the render as it progressed - often eliminating the wait for the end result before deciding to tweak the effect or sequence before rendering fully. This simple feature (also known from Procoder, Shutter Encoder and other video utilities, saved me time on many occasions, and when working up to a deadline enabled me to tweak without unecessary delay.

Could this be a feature for MC in the future?

(And yes, I write most of my forum postings whilst I'm waiting for MC to render :) )

MC had this feature back in the day. We lost it at some point. Either Meridien or DNA hardware prohibited it from working I think. Would be nice to get back, sure. Like many features we lost over the years (Superbin, bin colors, resizeble mixer, separare clip/auto mixers, etc.).

You can do a partial renders and see the results before you commit.

After you've  started your render, just hit Ctrl + . (period key). You should get a message box asking you if you want to keep your partial render.

Yes, but if the unsuspected fault - bad keyframe in an effect for example - comes later, you would miss it :)

Adrian Redmond:

Yes, but if the unsuspected fault - bad keyframe in an effect for example - comes later, you would miss it :)

Yes that's true, but how does having a preview box save much time? Having a preview window won't speed up rendering time.

If the error is at the end of the effect, you'll still need to watch and wait until you get to that section before you spot the problem.

I've found with some errors, you need to examine them closely (in slomo or inching a frame at a time) to spot the exact problem.

I've seen a better method on some compositing software where you can specify a region of interest. The smaller you make this, the quicker the render happens, as only this portion is rendered. 

The software designers at Avid could also help if they were to fully utilise any GPU hardware that was available. I know some tthird-party effects (eg. Boris) do use the GPU, but the Avid renderer doen't seem to benefit if you add a more powerful graphics card.

I am going to sound like a newbie by saying this, but isn't this what background rendering is for?

It's also a question having insight into what the platform is working on. On a complex timeline with a bigger number of renders, its good to know how far things are progressing. Not just quality control but also progress control :) (It was a useful feature and of course you didn't have to use it)

Background rendering is useful - if you know hat it is rendering. If for example, youy have a long timeline with a lot of 25 frame fades up and downs on captions - in parts of the timeline where you aren't currently working, then backround rendering works fine and saves time.

But if you are dealing with multi layer effects on clips that also have flexframe, slo-mo, and stabilization settings, then you probably want to render as soon as you think the sequence is complete - because otherwise it might not play back accurately enough for you to be able to judge the result - and setting such a workload to background render takes up valuable processing resources whilst you try to work in the foreground.

So it depends on the situation.

Curiously, back in the old FAST Liquid Silver days before powerful GPUs and CPU.s they made separate rendering engines as PCI cards - called InTime modules - to handle such jobs - you could add up to three cards to your host if you had enough slots. They were powerful but expensive. It's a pity that MC doesn't giove you the option of allocating GPU resources to rendering to take the load of the CPUs..

For what its worth, Vegas Pro allows this preview during render, of course, if the render is fast, so is the preview.