[Kenneth Kirkpatrick]

Try putting a compositing tag on the object (or probably group in this case) and render out an object buffer in the multi pass render. (Said tag is found in the Objects pane under Tags – Cinema 4D Tags.) Assign another separate compositing tag/object buffer to the perspective plane accepting the shadows. You can use that as a luminance key to separate the object in question from the rest of the stuff visible in your rendered file. For this separate render, just assign a white texture (in the color channel) with no other channels in the material. With no channels except color it should render pretty fast.

For the render, enable multiple channel rendering, and render out the two (or more) object buffers and the shadow channel. (If you render as picture sequences be sure to check the Multi Layer File box.) You can use the shadow channel as a layer in After Effects (set to Multiply) to put the shadow of the object(s) on top of the source video.

[Kenneth Kirkpatrick]

Justin:

I too would like to know how to smooth such points in C4D. My solution has been to open the paths in Illustrator and use the Simplify Paths command. It gives you a range on how much smoothing to do, and is much faster and a better jumping off point than what is available in Photoshop.

[Kenneth Kirkpatrick]

Above the view window open the FILTER tab and make sure there is a check mark in front of AXIS

[Kenneth Kirkpatrick]

I like the way the motion blur in C4D looks better than using any of the post blurs I have used in After Effects. I too have found that you can’t use object buffers to mask motion blurred renders.

Two ways you might approach it:

1. On a separate render, replace the texture on the blurred objects with 100 white in the Luminance channel of the texture, and make everything else in the scene black (0 in the Lum channel.) Don’t include any other texture channels (except Alpha if needed.)

Render without an Alpha channel: this image itself will be used as one. The scene should render very quickly (although the amount of blur will affect this,) and you will get a black and white image, with blurred edges, that you can use like an object buffer. (This will work best if you checked “Straight Alpha” in the render settings of the original full-color render.)

2. Render each blurred object separately, with everything else in the scene tagged with a Compositing tag that has “Seen by camera” unchecked. Make sure you check “Alpha Channel” and “Straight Alpha” in the render settings. In a separate render, tag all the blurred objects with a Compositing tag that has “Seen by camera” unchecked, and have all the unblurred objects visible. Set appropriate objects buffers for the scene. Then comp the blurred renders over the unblurred render, using the object buffers to mask to taste.

I would love to hear other methods, but each has worked for me. And, by the way, if anyone has told you not to use motion blur with interlaced rendering, listen to them. Interlacing and motion blur don’t work well in C4D.

[Kenneth Kirkpatrick]

I have had a similar problem in the past. My solution was to put everything intersecting onto different layers in Illustrator, and then save out each layer as a copy (after deleting all the other layers.) Then you open each as a new model in C4D, and copy each into a single model. They all end up in the correct position relative to each other, and you don’t have to figure out how to separate them like you do if they all come in as one lumped-together file.

Is this a clumsy way to do it? Is there a better way?

[Kenneth Kirkpatrick]

Nolan:

Thanks, but not quite there yet. Basically that just flattens all points to 0 on the Y axis. What I’m looking for is something that rotates each polygon so every corner point is alligned to the same plane, rather than squishing them down from above to be flat.

Ken Kirkpatrick

[Kenneth Kirkpatrick]

Nolan:

Thanks for your post. I looked at the tutorial, and it still includes some distortion of the polygons.

Another question, though: is there some way to select a polygon and then snap it to a construction plane?

I have been very careful in the construction process (through about 12 incarnations now) to keep all polygons perfectly flat. If I can individually or in a group snap each polygon to the same plane, without distorting any of their angles, then I can move them around so they don’t overlap and achieve the effect I am looking for.

Any ideas?

Thanks again.

Ken Kirkpatrick

[Kenneth Kirkpatrick]

Nolan:

Thanks for your reply. I have already tried Bodypaint, and I can’t figure out how I can get it to do exactly what I need. I want to be able to lay all the polygons of my object out flat, on a plane, undistorted in any way: all the exact same size and shape they occur on the model. Then I want to be able to render this out , print it on paper and be able to cut the pieces out and tape them together to form the model in the real world (it’s all flat planes, no curves.)

No matter how I have worked UV mapping in Bodypaint, it always adds some distortion in the layout, and when I print it out I immediately can see these distortions, scaling differences and angle misallignents when I cut out the elements and start contructing.

I even tried disconnecting all the polygons before I UV mapped. I still get distortions.

Any other suggestions? Someone told me there was an “unfold” command, but I haven’t been able to find it.

Again, thanks for your reply.

Ken Kirkpatrick

[Kenneth Kirkpatrick]

I agree with Aharon about a good quality hard drive. I learned a hard lesson by rendering to an external. I was doing a big project and the drive was spinning all the time and it wore out. One month after the warrantee ended.

Invest in a good drive, or render to the internal drive, and then move stuff to the external to make room for newer stuff.

[Kenneth Kirkpatrick]

Dave and Chris:

Thanks for both your responses.

Dave: I’ve kind of run out of ideas on what it could be, hence the posts. Shooting hasn’t changed: we shoot component video on Beta to avoid DV compression. We capture in this case in Avid using Meridian uncompressed 1 to 1 codec.

At first I thought it was the latest Avid codec, but then I was having the same problem when I rendered the sequence to the uncompressed None codec in the output dropdowns.

Chris: Flash isn’t at all in the picture. I’m not rendering the chromakeys out as matte channel files, but as comps over the background with audio.

The weirdest thing is, everything looks great in the comp window. Then, the instant I hit render, I see the image go soft.

Again, thanks for the input. I’m going to have to give it a rest and get back to my scheduled tasks.