Author Topic: White Fringe Around Render...?  (Read 4836 times)

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Offline DarkEdge

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White Fringe Around Render...?
« on: June 13, 2015, 04:45:33 pm »
I am rendering with transparency alpha check in the render for a clear background (tiff, psd, png), but in my render there is a white border that goes around the render?? How can I render without this white border?

Offline TpwUK

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Re: White Fringe Around Render...?
« Reply #1 on: June 13, 2015, 05:19:26 pm »
This looks like you need to copy the leaves material you are using on the ivy to the opacity swatch in the material editor, you might have to use colour or alpha to get it to clear up

Martin

Offline andy.engelkemier

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Re: White Fringe Around Render...?
« Reply #2 on: June 25, 2015, 05:20:37 am »
are you rendering with DOF turned on? If so, you'll never Really get rid of it. Photoshop does some tools under layers>matting to help remove that, however, it'll kill your shadows if you have any.
If you open that up in AfterEffects you can switch between alpha modes as straight - unmatted, or premultiplied with a color, in your case right now, it looks like white (unless that's just part of your backplate image)

Keyshot renders a premultiplied alpha on your background, but photoshop only opens as straight. So you can bounce it through after effects to fix that, IF you rendered with a solid color background. If you rendered with a background image, then you're hosed.

Offline Speedster

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Re: White Fringe Around Render...?
« Reply #3 on: June 25, 2015, 07:46:34 am »
For an alpha TIFF, try a solid black background color.  Usually works for me.  A must if you are also rendering ground shadows!
Bill G

Offline andy.engelkemier

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Re: White Fringe Around Render...?
« Reply #4 on: June 25, 2015, 08:35:06 am »
also, if you appreciate saving hard drive space, use PNG instead of tiff. 100MB files quickly turn into 7MB files. You will not see a difference in quality. The tiff's out of keyshot are basically saved as BMP with alpha. It's a straight up bitmap with no method of compression at all.
If you open the tiff up in photoshop, then just save a copy of it, it will instantly drop in size without a quality loss.

And if you Really want to see png vs tiff or yourself, just save the same image twice. Drop the png on a new layer and change the mode to difference. You'll see it as black. But there Is a small difference. So drop on an exposure adjustment layer and crank down the gamma (contrast). Move it far enough and you'll find that the edges are slightly different. Of course, quality? Probably subjective. You'll notice the same difference between tiff and bmp. So.....

Offline Rob Woods

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Re: White Fringe Around Render...?
« Reply #5 on: July 03, 2015, 05:38:41 am »
I can never completely get rid of the 'halo' so I drop the image into Photoshop and de-fringe it there, works a treat.

Offline andy.engelkemier

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Re: White Fringe Around Render...?
« Reply #6 on: July 17, 2015, 06:33:24 am »
I almost forgot. One more trick, if you're stuck with photoshop. AfterEffects really has a ton more control for this, and will likely be able to fix it by just changing the way the files are imported.

But, if you control+click on the layer thumbnail image it selected the pixels on the layer. If a pixel is partially transparent, it selects it by that value.
Now if you apply a layer matte using that selection, you'll cut those semi-transparent pixels down even further. Like that effect but want more? Just put that layer in a group, and apply the same mask to a group.

I hate to give away my secrets, but that's how I make ground shadows look correct. Ground shadows take too long if you actually bounce light off a ground plane, but are Way under exposed if you don't. 90% of the time it's the ground shadows that give away a realistic render right away.