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Rudy Daverveld
Member
Username: Visual_8

Post Number: 65
Registered: 09-2010


Posted on Thursday, August 02, 2012 - 10:11 am:   Edit Post Print Post

Hi All Zweb,

I rendered the ship on an alpha background and set the water to a background catcher. but I can see the underside of the ship thorough the background catcher. Is this supposed to happen? Doesn't seem logical to me though! Is there a way to prevent this without cutting the ship in half on the waterline? I don't want to see any of the ship what is under water.

Kind regards

Rudy
ship
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support@formZ.com
Moderator
Username: Tech

Post Number: 17103
Registered: 04-2001


Posted on Thursday, August 02, 2012 - 10:37 am:   Edit Post Print Post

Hi Rudy,

Nice boat! Does your water Material have a Transparency setting?

EDIT -- Yes, if the Transparency for the water is set to None, you should not get the bottom part of the boat showing. Thanks for your report, we will get this corrected.
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Rudy Daverveld
Member
Username: Visual_8

Post Number: 66
Registered: 09-2010


Posted on Thursday, August 02, 2012 - 10:40 am:   Edit Post Print Post

it's not transparant

settings
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support@formZ.com
Moderator
Username: Tech

Post Number: 17105
Registered: 04-2001


Posted on Thursday, August 02, 2012 - 10:42 am:   Edit Post Print Post

Rudy,

We edited our post above after we made a test file. If you change the Catcher Reflection to Mirror (and adjust the values as you would like) you should be able to get the rendering properly without showing the bottom of the boat...

Does this do what you want?
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Rudy Daverveld
Member
Username: Visual_8

Post Number: 67
Registered: 09-2010


Posted on Thursday, August 02, 2012 - 10:48 am:   Edit Post Print Post

Oh I see that you edited your post.

What can I do to prevent this? is it possible that this occurs related to the angle of the camera?

How can I work around this?
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Rudy Daverveld
Member
Username: Visual_8

Post Number: 68
Registered: 09-2010


Posted on Thursday, August 02, 2012 - 10:52 am:   Edit Post Print Post

That is not an option I think because I need the alpha channel to delete the background...

thanxs for the quick response!
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Rudy Daverveld
Member
Username: Visual_8

Post Number: 69
Registered: 09-2010


Posted on Thursday, August 02, 2012 - 12:06 pm:   Edit Post Print Post

Hello zweb,

I'm rendering now the file with the background as a background map and this seems to avoid the problem, but leaves me with no flexibility in the post process since everything is now in one layer.
But the problem lies in the fact that the background is an alpha channel.
Maybe this has a connection with the fact that the alpha channel also doesn't catch the ambient occlusion, a problem known now for several years. Hopefully these problems can be solved, I'm working more and more with composite images and animations. But the solution lies not within the reach of Autodessys but with Lightworks if I'm not mistaken.

Do you have any other workarounds then the mirror surface style?

kind regards.
Rudy
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support@formZ.com
Moderator
Username: Tech

Post Number: 17107
Registered: 04-2001


Posted on Thursday, August 02, 2012 - 01:21 pm:   Edit Post Print Post

Rudy,

There is an inherent conflict when using a Background Material with a Catcher Reflection AND and Alpha Channel background.

(The Background Material shows through to the background image -- but there is not one there because it is only an Alpha.)

Probably your best bet is to render in two passes -- one with the background image -- and one with the Alpha Channel and a Matte Reflection. Then copy the Alpha from the second render into the first, and use that to control the compositing.

Does this help?