skies - render in model or add in later.

[mresailor]

Thanks Codi... your discussion with rivoli lost me there with the premultiplied vs. straight outputs. I am assuming your are talking about the TGA output with Alpha vs something like a JPG (which is what I've been saving the images as..)

Also, I am also assuming that it depends upon the resolution of the image - no? See below - this is a close up of one of the images that I posted. Notice when I pick the black area - it sorta cuts out some of the leaves. I rendered the images at 1600x800 and this is zoomed in at 325% in PS...not sure if my computer can handle a 4000 dpi or something higher...

Also below is a composite I did using a JPG and selecting the black and working through the alpha channel thing on my own - prior to reading your post just now. I will work on some more tests this afternoon based on your directions. (need to work on the paying clients projects for now..)


By mresailor at 2009-07-24


By mresailor at 2009-07-24


As for the animation, I am thinking of just putting a dome around the model and rendering it that way... I really don't have the time to composite 1000s of images between now and Tuesday (not including rendering the animation...!) I might not do an animation at all - its not a requirement, just trying to wow the crowd and win the project...

[Codi]

I am assuming your are talking about the TGA output with Alpha vs something like a JPG (which is what I've been saving the images as..)

We were talking of different methods of storing images with Alpha information, you can check this tutorial to have a gasp of Premultiplied vs. Straight Render:
http://podcasts.creativecow.net/mult...traight-render

Saving renders in JPG is a bad idea if you want to composite a BG because this image format doesn't store alpha information, plus JPG is a file format that loses detail because of it's compression method, if you have to do any kind of adjustment in your images (a must for most renders), better save in a loseless one and convert to JPG at the end if you need to send it to someone.

As I see you have two choices: re-render and save with a more adequate format or try to select the background area with PS color selection tools as you are doing, but is hard to get a clean result this way.

Also, I am also assuming that it depends upon the resolution of the image - no? See below - this is a close up of one of the images that I posted. Notice when I pick the black area - it sorta cuts out some of the leaves. I rendered the images at 1600x800 and this is zoomed in at 325% in PS...not sure if my computer can handle a 4000 dpi or something higher...

Well, if you have ugly edges they tend to be less noticeable at higher resolutions as the "dirty" area is smaller relative to the size of the render. But better comp it correctly and forget about it

Also below is a composite I did using a JPG and selecting the black and working through the alpha channel thing on my own - prior to reading your post just now. I will work on some more tests this afternoon based on your directions. (need to work on the paying clients projects for now..)

To keep it simple: save your render in TGA. In the TGA options you must choose 32-bit and if you disable "Pre-Multiplied-Alpha" you can skip the remove black edges of my previous post as rivoli pointed.

As for the animation, I am thinking of just putting a dome around the model and rendering it that way... I really don't have the time to composite 1000s of images between now and Tuesday (not including rendering the animation...!) I might not do an animation at all - its not a requirement, just trying to wow the crowd and win the project...

If you don't have much time to experiment yeah, it's easier to have the environment inside the scene and render all in a single pass. When you get the hang of compositing you'll see is better to have it in different passes.

Good luck

[mresailor]

WOW..thanks.. this really helps me out. I have a much better understanding of this now. Thank you so much! This will help me sell the project better than the black or white backgrounds I was thinking that I would have to settle for...

[horoXhoro]

hi all...need help abit on alpha halo effects...in AE?

my situation is ..i have render a scene and i want to compositing moving character inside the scene...but all the character have black border..(render with black background) all in TGA 32bit premultiply i even split the alpha...i tried to used other mask with alpha still no luck..only reduce abit the blackborder.
how to I get rid of those black border in AE CS4?

pleeease help thank u!!!

[tammo]

Check the settings of the imported footage in the "interpret footage" options,
you can also try to change the matte color there if you rendered with premultiplied alpha.
AE sometimes sets the wrong mode.

If that doesn't help you can apply a filter to the footage to shrink the alpha, like "matte choker".