Rendering a Transparent Background?

[Anonymous]

Does anyone know how to render in lightworks a transparent background so that when I open my .jpeg in photoshop it can directly overlay on another image? I know how to render a color or an image but I don't want any background at all...I only want my 3D model to render.

[TomWaltz]

I don't believe there is a direct way. Your best bet may be to leave it white or some other color then magic wand it in Photoshop.

[Anonymous]

JPG formatt does not allow transparency, so I think you have to render with a solid single colour and magic wand / delete it in Photoshop.

[stefan]

Render to TIFF? JPEG is a "flat" file only. No alpha channels

[Anonymous]

try rendering using artlantis 4.5 as a targa (TGA) image
all the transparant stuff will have an alpha channel

i've been trying to do the same thing with artlantis R 1.0.0 but it didn't work...anybody now how come?

[Anonymous]

I think that You can rendering your model with standard ArchiCAD Render Engine and saving like tif with +Millions Colours options. You should get an image with alpha channel.
With Photoshop or other photo editor you can copy alpha mask from this image to your LW render image.
You should unplug an transparent background option in standard engine windows dialog.
I was try this process and work fine.

[gerd]

henry_use_archicad wrote:
i've been trying to do the same thing with artlantis R 1.0.0 but it didn't work...anybody now how come?

hi,
when you work with artlantis-r you can render the image in photoshop format. then you get the background image, the fog, the model ... on separate layers. so you will be able to make them visible/invisible

but you should make an update to 1.0.2 (the psd format had some problems in the former versions)

best regards, gerd

[Anonymous]

I don't have artlantis just ArchiCAD & Photoshop.

Marissa

[__archiben]

Marissa wrote:
I don't have artlantis just ArchiCAD & Photoshop.

marissa - i don't know how much photoshop experience you have, but the guys in the posts above have the right idea:

render the background with a bright vivid blue or green - or whichever colour is so at odds with the rendering palette that it is easily selectable with the photoshop's Select>Colour Range... command. by altering the 'fuzziness' you can be sure to select the entire background. this also helps you select background that may have been altered slightly by transparency effects, but you do have to be careful that lightworks doesn't reflect too much of whichever lurid colour you choose onto the image

. . . then press 'delete' and it's gone - leaving you with an image to overlay as you wish . . .

this is the same principle as 'blue-screening' in movie making when action is played out in front of a 'blue screen' and composited with other images later . . .

HTH
~/archiben

[stefan]

As much as rendering with a green background makes selection simple, it has it's own set of problems: the aliased edges will be smoothed against green, instead of against your real background color.
And the color might reflect...

If you don't have Photoshop, you can try other applications:

Paint Shop Pro
Last version has better support for Alpha-channels then previous ones...
http://www.corel.com

GIMP (free and opensource)
http://www.gimp.org

Corel PhotoPaint (included with CorelDRAW)
http://www.corel.com

Photoshop Elements (= lite version, which often comes with scanners)
http://www.adobe.com

Paint.NET looks a nice (and simple) clone
http://www.eecs.wsu.edu/paint.net/

[Anonymous]

the method archiben described is the same method I always use, But I typically use a very bright blue colour, so that if it reflects back, it won't necessarily look bad, I guess I've always assumed if it is visible it might look like a sky reflection, or something of that nature. As far as the anti-aliasing goes, a steady hand and a brush tool are all I can suggest for that.. oh and 3200% zoom

HTH,
dan

[Anonymous]

save a targa TGA image from you 3d rendered window,
open it in photoshop, if it's right you'l have an alpha channel in the channel layers window
disable the others, and collor sellect the alpha channel with fuzzines of 170 to 180
then activate the others (don't unselect yet)
go to the image layer then delete the selected stuff
...
yes i think that's it