[quote=“LuisRP, post:1, topic:510697, full:true, username:LuisRP”]
Greetings to all of you, we are using LiveLinkFreeD and UE 4.27 to build a virtual studio for broadcasting. In order to do that we are trying to control our virtual cameras with LiveLinkFreeD so that they behave in the same way as our real PTZ cameras (Panasonic UE-100 and UE-150) do. The pan and tilt work fine but we can’t get the zoom to work properly.
It seems like Epics FreeD plugin doesn’t support zoom and focus out of the box so we tried two different ways:
- Add the LiveLinkCamera plugin which activates the option to add a Camera Role to the Role Controllers of the LiveLinkComponentController
- Create a small blueprint which handles zoom and focus by evaluating the LiveLink frames
Both ways change the focal length of our virtual CineCam based on the lens parameters of the FreeD package.
Furthermore, we found out that the FreeD protocol returns the zoom as a float between 0 (tele) and 1 (wide), which is why we use lerp to interpolate between our actual min and max focal length based on this number.
Our problem is that the virtual camera zooms in a different speed compared to the real one and therefore makes the zoom unusable.
We did some testing and came to the conclusion that the PTZ cams of Panasonic don’t zoom linear between min and max but instead use some kind of exponential lens curve in order to make the zoom feel more intuitive. Sadly, Panasonic doesn’t add this lens curve to FreeD which is why our virtual and non-virtual cameras don’t behave equally.
Things we tried and didn’t solve anything:
- Make sure that CineCam has the same lens and filmback settings as the PTZ cameras
- Disable ‘Speed with zoom Position’ in PTZ camera controls
- Replace lerp with typical functions (exponential, logarithmic, etc.)
- Replace lerp with an a^x function and changing a until the zoom is neither to fast nor to slow (not possible it’s always one of both)
- Changing the LiveLinkFreeD Panasonic Preset p