Perspective renders projection mapping.

  • I am setting up for a projection mapping project where all the content is made in cinema 4d against the model of the building. At the moment I am planning projection positions. I have a couple of choices and wanted to get an opinion. I can render whatever viewport I want from cinema 4d, I have two options for the projector positions, of course I prefer the on axis, but the distance is big (100m with 2x 40k lumen projectors). I can also go in closer but well off axis. I was wondering what is a better approach, to calculate the projector positions and render in C4d from that viewpoint, or to take a standard front on perspective render and warp the hell out of it with Isadora. 

    I guess the biggest risk is once on the ground, the position and lens extrinsics of the projector will not be 100% exact, but I have less warping to do with Izzy (but very little room to move if I want to move the projectors). 

    I am leaning toward the on axis long distance and minimal warping but am curious to get another opinion.


  • Beta Platinum

    Personally i'd go for less warping, so keep it on the axis. Also with the long distance you should in theory be able to use more of your pixels. 40K is bright so the falloff should be minimal. (Are they laser projectors by any chance? - Just being nosy!)

    I'm sure you'd do this anyway but it may be worth rendering a front on view as a back up anyway. For any last minute unexpected surprises. 

    As you've said trying to calculate the exact position is always difficult; it is never 100%. 

  • @Skulpture  no lasers

    Of course I prefer on axis. I'd you ever do an off axis render for mapping like this?

  • Beta Platinum

    @Fred Ah nice!

    Barco were on tour and recently called into my place of work (Production Park). They have some awesome new laser projectors - and they are small! Anyway...

    I have been quite lucky with my projector placement i'll be honest. When its off axis I know you can have problem with focus and anti-aliasing, etc. But it obviously depends how much off axis we are talking.