Perspective matching?

TurnerTurner Posts: 116
edited December 1969 in Carrara Discussion

Hi all-

In the past (probably C6) I could swear I saw a method someone was using to use a photo backdrop to use as reference to match its perspective, then to create content and render the content...

then overlay back into the original photo.

Any idea who/where that may have been¿

thanks,
Andrew

Comments

  • evilproducerevilproducer Posts: 9,050
    edited August 2013

    What you're describing are really two different functions. The first function is in the vertex modeler. Carrara can import pictures to use as references when building models in the VM.

    The second function is in the Assembly room where you build the scene. Select Scene in the instances and then under the general tab, select the pulldown menu under Backdrop to load your image. The image you select, and the aspect ratio of your final render should match otherwise the photo will appear distorted in the final render.

    The next thing you need to do in the Assembly room when using a photo in the scene's backdrop is to go to the Interactive Renderer. It's the little icon that looks like an up arrow with a circle around it, near the top right menu bar of the Assembly room window. Click it and a new window will open with the Interactive Renderer settings. Under Display Options, enable the Show Backdrop option. When you click Okay, you should now see your photo. The framing will be exactly what the camera sees. Anything outside of the photo area is off camera.

    A note about the Interactive Renderer: Whatever options you choose, will not effect the final render. Only the options you choose in the render room will effect your final render.

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    Post edited by evilproducer on
  • DartanbeckDartanbeck Posts: 21,549
    edited December 1969

    If memory serves - I believe it was called Synth-Eyes(?) something like that.

  • DartanbeckDartanbeck Posts: 21,549
    edited December 1969

    Whoa! Hi EP! I'm gonna go read what you wrote! lol
    I thought the OP was referring to that guy that was showcasing... I think it was called synth eyes!

  • evilproducerevilproducer Posts: 9,050
    edited December 1969

    Something to help with compositing 3D elements with photos or other pictures are shadow catchers. It's basically a shader that is invisible. It does two things: It catches shadows and it can mask out whatever is behind the object that the shadow catcher is applied to. It is invisible except for the shadows that fall on the object(s) it's applied to.

    To create a shadow catcher, go to the Texture room, and select Edit--> Create Master Shader. A new shader will open. Select Lighting Models--> Shadow Catcher at the top of the Shader tree. Note that if you select a color in the color channel, it seems to affect the hue of the shadow. Reflections, Highlight, etc. have no effect. A shadow catcher will not catch reflections.

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  • TurnerTurner Posts: 116
    edited December 1969

    Hey guys- I'm actually probably describing this wrong...

    I have created an object already- let's say a window.

    I have a picture of a wall on some undetermined angle...

    Basically, I want to "put the windows on the wall" - I'd like to render in C without the background image, and composite in photoshop....

  • evilproducerevilproducer Posts: 9,050
    edited August 2013

    Here's an example of using a video in the Scene's backdrop (choose Map for still images and video), and a shadow catcher. I used the shadow on a simple plane and on animated, replicated grass. Remember: the shadow catcher masks any object behind it, that's why the grass worked.
    http://youtu.be/_8puXTRXt7Y

    Would help if I pasted in the link now, wouldn't it? ;-)

    Post edited by evilproducer on
  • evilproducerevilproducer Posts: 9,050
    edited August 2013

    Turner said:
    Hey guys- I'm actually probably describing this wrong...

    I have created an object already- let's say a window.

    I have a picture of a wall on some undetermined angle...

    Basically, I want to "put the windows on the wall" - I'd like to render in C without the background image, and composite in photoshop....

    Okay, then you'll want to go to the Render Room and under Output, select a format that can handle alpha channels and then enable the little Render Alpha Channel checkbox. I usually leave the Pre-multiplied option off, but that's just my personal preference.

    The advice I gave above, about the interactive renderer will still be able to help you get the window at the right perspective on the wall. If you have the Alpha Channel enabled in the render room, it won't composite the backdrop photo unless you have the pre-multiply option enabled.

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  • evilproducerevilproducer Posts: 9,050
    edited December 1969

    Whoa! Hi EP! I'm gonna go read what you wrote! lol
    I thought the OP was referring to that guy that was showcasing... I think it was called synth eyes!

    Hey Dart, looks like we're both wrong! ;-)

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