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_wim_
11-23-2005, 08:18 AM
Hello,

I am rendering with fprime 2.10. I want to save my alpha channel so I save my render files as tga files. On the fprime dialog I click on the alpha button.
When I open a render in photoshop and when I look at the alpha channel, I see al my objects semi-transparent. normaly it should be black and white.
this problem occurs ocasionally. With other objects in others scenes I don't have this problem.
link: http://users.telenet.be/cosmicsnow/lightwave/alpha.jpg


Can somebody tell me what I'm doing wrong?

greetings
wim

toby
11-23-2005, 12:18 PM
First silly question, none of the objects have any transparency, including shaders, right? Just checking -

I think FPrime does have problems with tga's, try another format - like .psd :)

_wim_
11-24-2005, 01:09 AM
I think FPrime does have problems with tga's, try another format - like .psd :)

I've tried rendering to psd but the alpha channel is still incorrect.
I don't use any transparent surfaces.

toby
11-24-2005, 01:39 AM
D'oh.

I can only suggest a work-around - set your transparecy to .001 and turn on raytrace transparency. Sounds goofy, but it may force Fprime to give you a 99.99% opaque alpha. I've seen this work on other things, having any value in the transparency channel acts like a switch and renders differently.

You may also have success by just adjusting the alpha in Photoshop. Use Levels to turn everything grey into white.

_wim_
11-24-2005, 02:31 AM
D'oh.

I can only suggest a work-around - set your transparecy to .001 and turn on raytrace transparency. Sounds goofy, but it may force Fprime to give you a 99.99% opaque alpha. I've seen this work on other things, having any value in the transparency channel acts like a switch and renders differently.

You may also have success by just adjusting the alpha in Photoshop. Use Levels to turn everything grey into white.

thanks for helping me.
setting the transparency to 0,001% doesn't work eather. I'm now trying to change my surface settings but I've found no solution yet. The strange thing is that I don't have this problem in every project I make. this is the second project I've encountered this problem.
Adjusting the alpha channel in photoshop is not possible because some parts of my object are completely missing.

I've tried rendering with the lightwave renderer (pressing F9) and the same problem occurs.
here's an image with alpha and render.
http://users.telenet.be/cosmicsnow/lightwave/render_v015.jpg

_wim_
11-24-2005, 03:29 AM
I've rendered the file on mac and pc with different Lightwave versions, both are incorrect.
I've made a new scene and I reproduced the problem.
Can somebody check what I'm doing wrong?
greetz
wim
http://users.telenet.be/cosmicsnow/lightwave/3d.zip

toby
11-24-2005, 04:53 AM
In the Advanced tab of the surface editor you have the Alpha channel set to 'unaffected by object'. It should be 'surface opacity'.

_wim_
11-24-2005, 05:53 AM
thanks a lot man,

it works. But I don't remember changing that setting and I made everything form scratch.
So it's still a little bit weird ;).

_wim_