So I am coming more from a production world and using Unreal to render out visuals for a projection mapping project. The screens are all unique sizes .
The only way that it seems like you can set up a camera’s window size is in milimeters ? This is boggling my mind. yes you can render out to a specific frame great if you are doing standard sizes but if your camera window doesnt match the ratio it renders with black bars . So getting 3-7 camera’s to all be seemless together is really challenging . If my final image is 16,350 x 1550 as an example . Can someone explain this ? In every other compositing or editting software I’ve ever used the comp is defined in pixels . Every job I’ve ever delivered has been in pixels. Why can’t you set up your camera at the beginning in pixels ? - Can I use nView somehow and render from that ?
Well, you often want to know both the pixel size AND the lens size. The units are sort of irrelevant, but the ratio is key!
I also find it a bit confusing the way to set it up, but it’s doable!
I typically use either Maya or After Effects to figure out what the camera numbers should be for Unreal. The thing I find annoying is that you can’t just set the aspect ratio and have Unreal determine the proper values! That box is greyed out. But if you’re using any other software that has cameras - Maya, for example - you can usually figure it out.
First – So the render size, in Unreal, you set when you actually render - there you set the pixels.
Second – for the camera itself, you need to know the ratio. Sensor Width, vs Sensor Height.
For example, if you want to render 1920x1080, that’s a device aspect ratio of 1.778.
So in Unreal, you’d set the camera sensor width vs height to the appropriate numbers (which again, you can use other software to figure out). In this example, it would be 26.7 x 15
To figure this out
If you’re using Maya, set your render settings to the proper pixel size. At the top of the render settings, you’ll see a bit that tells you, in inches, the ratio. This goes into the Unreal camera sensor size.
If you’re using After Effects, create a comp that’s the proper pixel size, then create a camera in the comp. In the camera, you’ll see on the right side the size of the comp (in inches again). That’s the sensor width. You can divide that number by the ratio (in the 1920x1080 example you’d divide 26.67 by 1.778) – this will give you the height number!
Here’s a pic of the MAya / After effects thing
And here’s a pic of the camera in Unreal
I hope this helps!
It helps a little - though super jenky way of setting up a render out system