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View Full Version : Grey border on objects in transparent image when using Antialiasing



F_GX
05-27-2010, 01:15 PM
Hi community,

i'm trying to render a image with transparent background, i'm saving as PNG32.

The problem is if i turn on antialiasing, i get a grey border around all objects. Is there a way to avoid that? Please have a look at the two pictures i attached.

I really need AA (at least enhanced low) so disabling it is no solution.

Thanks a lot.

Nicolas Jordan
05-27-2010, 01:23 PM
Sounds to me like you are using the "classic camera". I recommend switching over to using the newer "perspective camera" instead and setting the antialiasing to 3 or so and turn on adaptive sampling and set the threshold to .1 or .05 and you should hopefully get a better result.

F_GX
05-27-2010, 01:27 PM
Ah yes, thanks for your suggestion i'll give that a try. I know i really should get rid of using the classic cam all the time...

edit:
hmm no success here ;(... any other ideas?

edit2:
ok i have now a photoshop solution for this, which is in fact, not really a solution, but for now it's ok. Still wonder how to do it in LW.

http://www.underwaterphotography.com/PhotoShop/PhotoShop/1_9_9_0.html:

"To decrease a fringe on a selection:

Choose Layer > Matting > Defringe.
Enter a value in the Width text box for the distance to search for replacement pixels. In most cases, a distance of 1 or 2 pixels is enough.
Click OK."

edit3:
also playing around with an image filter called "spriteedger" did not really help, although with lots of tuning it might work, however, the overall quality of the antialiasing suffers a lot from using it.

BeeVee
05-27-2010, 02:07 PM
The grey is cause by averaging out the colour of your box with the background. I'm guessing the background in LightWave is black and you are trying to put the transparent object onto a white background in Photoshop or similar? Try using a different colour for the backdrop in LightWave and you'll see that edge change colour. Just as an experiment, so you understand how it works, go for a bright pink.

B

F_GX
05-27-2010, 02:26 PM
Ladies and Gentleman: the solution. :lwicon: = :thumbsup: