The conversion table
Ever wanted to set the camera FOV (Field of View) as an angle in degrees, when Clip Studio Paint will only let you enter some obscure 'Perspective' value? Well, you're in luck! Here's a conversion table:
OK, so how does it work?
For starters, you need to add some 3D object or character to your scene, as CSP automatically creates a new camera for each new 3D layer. Make sure that the 'Object subtool' is selected, like so:
Select any 3D object in your 3D layer. Then in the 'Tool property' panel, click on the drop-down button to open the object list, and select the Camera:
Click on the drop-down button again to close the object list.
Aha! Here's the culprit, the dreadful 'Perspective' slider with its despicable 4.72 default value! Ok, this is the value you need to change to set the camera horizontal FOV:
Choose a FOV angle that suits your needs (let's say 30°) and refer to the conversion table to get the corresponding 'Perspective' value (2.68 in our case). Enter that value. You're done.
In the screenshot below, I've included a compass around the camera to check out visually our previous example. A 'Perspective' value of 2.68 has a FOV of 30° (15° on each side of 0°):
How about the default 4.72 'Perspective' value, you may ask? Well, the conversion table yields a FOV of something between 50° and 51°, as you can check out on the following screenshot:
What if I need an angle that's not in the conversion table?
The conversion formula is simple:
Perspective = 10 * tan(FOV/2)
FOV = 2 * atan(Perspective/10)
See below, in the Top view of 'Window > All sides view' (available in CSP EX):
For instance: 4.72 = 10 * tan(50.5°/2)
So there you have it! You can set the camera FOV angle like a pro!