DaVinci Resolve Render Cache Essentials
If you’ve ever used graphics templates, noise reduction, or done anything in Fusion, you probably didn’t have real-time playback on your timeline. Have you seen this light go red in the viewer? Well, renders are the answer - but Resolve has two ways to render. There’s a Render cache, which is ideal for work-in-progress automatic background rendering. And there’s Render in place, which is great for collaborative projects and heavy fusion comps. But if you REALLY want to tame your timeline and know the best settings, let’s dive a little deeper…
What’s Render Cache?
Just like when you browse the internet, parts of websites get cached (or stored) on your computer hard drive so its faster to load the next time, Resolve can do the same thing by storing calculated frames in your codec of choice. It’s baking out that frame with all the debayering and changes you might have made to show it on screen as fast as possible. The image sequence frames are stored in a proprietary DVCC format and cached at the Timeline Resolution.
They only work on a single Resolve system and can be turned on easily by going to the playback - render cache and clicking smart or simply hitting the keyboard shortcut option or alt R. Smart is the automatic mode.
In smart mode, the timeline should go RED for clips that are RAW, h265, fusion titles, effects & comps, transitions, overlayed composites, or noise reduction’s used. You know, stuff that is difficult for any computer to tackle on the fly Resolve will “pre-render” when the machine isn’t in use for 5 seconds. If you need the entire timeline rendered, park the playhead and take a break away from the computer,
And will turn BLUE after they’re rendered. A great tip I learned from Patrick Sterling is to turn on the option to show all video frames if you can’t wait for the machine to do a background cache.
If you edit any changes, Davinci Resolve will update the cache file automagically.
However, sometimes you DON’T want your computer to render ALL H.265 or RAW files. See in smart mode render cache skips over H.264 and ProRes on my timeline, but my computer can play H.265 just fine so I want those skipped too. So to for more control - under the playback menu choose the user mode. This is MOSTLY manually controlled by right clicking on a clip and tagging the level of cache you want rendered and selecting the color output cache is the final manual render operation. I say mostly manual, because if you open the project settings there are a few other checkboxes to auto-trigger renders even in user mode. I suggest turning all of those boxes on.
The cache builds up based on this order of operations:
Edit Page - Fusion output cache
Edit Page - Manual enable OFX & Fusion Filter cache
Color Page - Node cache
Edit Page - Color output cache
Edit page - Sequence cache (transitions, opacity/supers, adjustment layers, retimes)
So, if you change an earlier cache operation, the rest will need to be re-rendered when you take that coffee break.
What’s Render in Place?
Render in Place bakes out a shareable video file, almost as if you went to the deliver page, exported the file, and brought it back into the timeline.
Using the right-click option to render in place is the surefire way to get excellent real-time playback, regardless of your rendering effects.
Because I often use Render in Place, I set this to a custom keyboard shortcut: shift R.
I tick all the boxes except for color grading effects so that I can grade on top of the file as long as you choose the correct codec settings that are coming up next.
It’s essential for working in DaVinci Resolve multi-user collaboration when another editor opens your work.
And this is a key takeaway: Render Cache writes files to be used locally on your fastest SSD VS Render in Place writes an exported file that can be used on shared storage or synced with Blackmagic Cloud.
Other benefits of Rendering in Place include the checkbox to add handles (10 is a good idea for editing flexibility and including motion blur at the start frame in fusion comps) and rendering using the Source Resolution—all of those original pixels to retain the source quality.
Remember, render cache renders at the timeline resolution, so it is a bit more fragile and needs re-rendering if you need to make social aspect ratios.
For edit changes, you need to right-click to decompose to the original, which must be done from the timeline. You can’t pull this rendered clip from your media pool to another timeline and decompose it; it will lose this unique decompose superpower. And each time you make a new version, you make a new file; it’s not overwriting the render cache sequence.
Pro Tip, if needed - you can batch render the entire timeline at once, then the same goes for when you need to decompose to the un-rendered files.
Render Cache Best Codec Settings
For Render Cache - go to your project settings in the lower right gear cog icon.
Master Settings—Optimized Media and Render Cache section—By the way, I would avoid ever using what is called “optimized media” in resolve. This is a legacy thing. Proxies are a better way, and I have a recent tutorial on that.
Choose the “Render Cache Format.” If you’re on a Mac, choose ProRes 422 LT. If you’re on Windows, choose DNxHR SQ. I’ve tested these a ton. They’re similar in quality and won’t fill your SSD too fast.
I leave my background cache to 5 seconds, which is how long the computer needs to idle before caching. At this point, I would save the project settings in the upper right three-dot menu to “set current settings as default preset.”
A quick note about projects where you might enable collaboration: This forces a brand new cache to be created. Collaboration Cache is per user and really shouldn’t go to a network storage device. I would not suggest flipping between collaboration on and off unless necessary.
If you ever have a corrupt cache—which does happen—select the clips that aren’t displaying correctly or display as offline, go to the playback menu, delete the render cache, and choose the selected clips.
When the cache drive fills up, delete the Render Cache under the Resolve Playback Menu. Scroll down to Manage Render Cache, Choose the type of project library and its name, select the checkbox, and then clear the selected cache. You can sort the size by clicking the Render Cache column header to find the bigger projects that need cleaning up. And don’t worry. Your computer will rewrite these files next time the project is open.
This is a Pro Tip for my Fusion friends. Fusion has its own render cache to disk option, but I never found this to work great inside of Resolve. Instead, I suggest using a saver node, as I do in this tutorial on saving magic masks. This kind of acts like a render in place for just within the fusion page.
Render in Place Best Codec Settings
For Render in Place, on a Mac - use ProRes HQ for all Prosumer footage like from a Sony FX3, or ProRes 4444 for Raw footage and Graphics that need transparency.
On a windows computer - DNxHQX 10-bit for Prosumer footage and DNxHR 444 12 bit for raw and graphics.
If you run out of storage space, you can manually delete these files from Windows Explorer or Mac Finder. But actually - I don’t delete render-in-place files.
The one downside to Render in Place is that you lose the clips source timecode. But like most things I teach here in Resolve - I have a simple solution in a new tutorial releasing very soon.
Storage Locations
For Render Cache - In the Project settings - Scroll down to Working folders. Make sure your cache files location is set to “CacheClip.” There should be no space in there.
This will use the first drive in your DaVinci Resolve Preferences - System tab - Media Storage - directory location. To avoid confusion and to fill up your operating system drive, I suggest getting a Samsung T7, T9, or similar drive and pointing all of these temporary files there.
For Render in Place - this is chosen when you run the manual render in place command - I place all of mine in the job-specific folder that contains all of the elements for the project.
Final Delivery
On final export for your full timeline, Resolve will use Render in Place Renders, but it won’t use Render Cache Renders.
If you want to change this behavior for Render in Place - right click to decompose your clips
And for Render cache to actually be used, although I never do this, the deliver page - advanced section under video has a checkbox for use render cached images. This could maybe speed up your final export, but I found it doesn’t always.
