I represent an agency that creates 3D illustrations for architects.
In our workflow, like many other studios, we work with large 3D scenes stored on a central server, so our team members can access and work on them from their Windows computers.
We’ve been using Cinema 4D and Corona Render for many years (Cinema 4D S22 and Corona Render 9 Hotfix 1). Recently, we decided to upgrade to the latest versions — Cinema 4D 2025 and Corona Render 13 Hotfix 2.
Since making this change, we’ve been facing a major issue with scene loading times. Previously, a 2GB scene would take around 50 seconds to open, but now the same scene can take up to 20–30 minutes to load in the latest versions. This waiting time is impossible for us to manage within our production schedule, and it severely slows down our workflow — especially since our clients expect fast turnaround times.
We have spent several days investigating the issue ourselves, searching online forums and running multiple tests on different 3D scenes, but we haven’t been able to solve it. However, we have identified that the problem may be related to Corona Render materials — since scenes without materials open just as quickly as they did in the older versions.
As we produce realistic and immersive visuals for our clients, simplifying the materials just to reduce loading times isn’t an option for us. We therefore need your help to find a solution so we can open our scenes as quickly as before.
Is scene loading also slow when all project files and assets are stored locally instead of a network location? This would help us verify if the issue is related to network storage or not.
Are you using some 3rd party antivirus and/or firewall software? If so, can you disable it for a short time and check if scene loading would be equally slow? Antivirus/firewall software is the first suspect in such cases.
And lastly, can you archive a sample problematic scene with all assets (File > Save project with assets) and attach it to a support ticket here? https://support.chaos.com/hc/en-us/requests/new
To answer your questions: our assets (maps) are stored locally, and the scenes are on the network. We don’t use proxies.
We tried moving the scenes to local storage, but that didn’t solve the issue.
We also tried disabling the antivirus and firewall, but that didn’t change anything.
For your information, we also tested with Corona versions 12 and 11, as well as Cinema 4D 2024 — the problem still persists.
Please find attached a screenshot showing the loading time of the test scene that we are going to send to support.
It takes 11 minutes and 37 seconds to open the scene.
With Cinema 4D version 22 and Corona 9 Hotfix 1, the loading time is only 1 minute and 8 seconds.
We can see in the Task Manager that the loading bar reaches 100% within about 15 seconds, and then we have to wait another 11 minutes and 15 seconds before the scene appears in the viewport.
We’ve just tried loading the scene with all the resources placed in the TEX folder, and indeed, the loading time is much faster.
However, we can’t work by duplicating the textures into the TEX folder for every project, as that would create a storage capacity issue.
Each of us has a local texture library that syncs with the NAS server, so everyone can use the resources locally.
I’m experiencing the exact same issue as Willy described above — extremely long scene loading times with the latest version of Corona (13 hotfix1) and Cinema 4D (2025.3.2) Windows pro 11
Here are my observations:
• The loading bar reaches 100% quite fast (around 10–20 seconds), but then Cinema 4D freezes for several minutes before the scene finally opens with the textures.
• The issue occurs on local drive, my pc.
• Moving the textures into the TEX folder significantly reduces the loading time — but, as mentioned, this is not a viable workflow for us either (too much data duplication).
It looks like the delay happens after the scene is technically loaded — maybe something related to texture path resolution or asset checking in the background?
If any of the Corona Team or other users have found a workaround or know whether this behavior is being investigated, I’d be very interested to hear about it.
Thank you for your suggestion! Unfortunately, I tried unchecking and checking the “watched folders” option, but it didn’t resolve the issue on my side.
Hello, thank you for this solution.
It doesn’t work for us.
I’m testing redefining the texture path to absolute on a large 4GB file c4d.
It’s taking a while, I have 574 materials to process.
Does anyone know a plugin or script for this?
I’m afraid the problem isn’t with Corona, but with Cinema4D’s database indexing.
Yet we did create a database linked to our local library and indexed it.
The indexing took 50 minutes.
We save on scene loading time, but it’s still five times longer than when we work on Cinema4D S22.
My next test will be to create a scene directly on this 2025 version.
Have a good day
Willy
Maybe this helps also a little bit.
As C4d is looking first for textures in a “tex” folder on the same hierarchy as the .c4d
file itself ( when there is one), I do the following:
create a ‘tex’ folder and put your main textures in it.
create a symbolic link file of that folder ( also named ‘tex’)
Copy that file over to every .c4d file
On a Mac you can create that file via the Terminal or you get a small app helping out.
! This is not an Alias- file !
On Win you do that as well.
Now C4d reads directly out that tex-file instead of searching a complicated path to it.
