Corona 12H1 Scaling issue

[PastaJackal]

Came across a serious issue, where now the VFB doesn't scale or display 1:1 resolution as it had in previous Corona versions to 12, which makes it very difficult to view my renders when unable to view them at native resolution

I've attached some screenshots of my display settings in Windows, as well as some anomalies found when observing the zoom level inside the VFB (top right). Same issue persists when switching back to VFB 1.0

[maru]

This is a known issue. We have it logged in our tracker and hopefully it will be fixed.

It seems that this issue only appears in 3ds Max 2024 and older. Could you please try with 3ds Max 2025?

[PastaJackal]

Thank you Maru, however as I work in a studio that requires us to all run the same max version, it would be too difficult to update just for this issue.

Is there any way to fast track a fix? As you can imagine, it is difficult to render anything when the resolution is so low - and my main job is to render :/

[maru]

The only workarounds I can recommend are:
- switch to 100% scaling in Windows
- keep the >100% scaling, but switch to the old Corona VFB:

Starting from Corona 12, the VFB 2.0 is the default Virtual Frame Buffer. If you want to switch to the old Corona VFB, you can do it from Corona Render Setup > System > System Settings > VFB Settings > Corona VFB.

Source: https://docs.chaos.com/display/CRMAX/Corona+VFB+2.0

[PastaJackal]

Thanks Maru, however I already tried the original VFB inside corona 12 and the same issue persists

[PastaJackal]

Just double checked and VFB 1.0 doesn't fix the issue

Changing windows scaling to 100% would be great, however all text would become far too small (4k res on 27 inch monitor)

[maru]

That's odd. Which exact version of 3ds Max are you using?

I tried reproducing this with 3ds Max 2024 and the legacy VFB works as expected. (see screenshot)

[maru]

(same in Corona 12 HF1)

[PastaJackal]

Hi Maru, thanks for testing!

I'm using Corona 12H1 and 3ds Max 2024.2.3

I've attached a screenshot of my max so you can check the VFB scale too (which is reading as double the resolution)

This test is from using IR. Production rendering seems to show the correct scale

Maybe worth noting that I'm running windows 11 as well

[maru]

Oh, I am sorry for the confusion! I case of IR we automatically detect if Windows scaling is above 100% and then we use an option which makes the render appear "zoomed". This is to keep IR responsive on hi-res displays such as 4K. The option is called "Image upscaling factor" and you can find it in Render Setup > System > System Settings. Setting it to 1 will make your IR appear as you would like it to.

For the record, this is mentioned here: https://support.chaos.com/hc/en-us/articles/28652797085969

[PastaJackal]

That's perfect, thank you Maru!

[alexyork]

Another case where corona setting the IR scaling factor to anything other than 1.0 is a mistake, in my opinion, but I've stated my case for this many times over the years :) Comes up very frequently. I really think it makes more sense to have it at 1.0 and let the user decide if they want or need the IR speed boost of changing it to 1.5 or 2.0 or whatever they want, and avoids this issue and the issue of people wondering why their IR previews look soft/blurry. It's a pain when you install a new Corona version and this value seems to change back to default again too.