How to obtain a white background that doesn't effect your object

[Brute Guy]

Hello,

 

A very quick one I hope, I have a scene which I have been rendering against a black background, when I do post work on my render in photoshop, I end up having to remove the black fringe around the object that I rendered.

 

Is there a way of rendering against a white background without the back ground lightening or effecting the object in the scene.

 

I have tried to change the background colour in the enviroment tab, but this often brightens up my the tones on my object?

 

Kind Regards

 

Marc

[Tommy L]

You could use the override in the Vray panel? However, the alpha channel shouldnt carry the black fringe. Maybe you need to up the AA settings? Could you post an example?

[BrianKitts]

you shouldn't have a black fringe if you are saving out your alpha channel properly. what format are you using, and are you using the pre-multiply option?

 

perhaps you are trying to fix this the hard way....

[notjeff]

I agree w/ the past two comments.

 

Another idea is just to make a white plane or interior box that contains the background you would see in post for your "background." Keep the backgound settings in the environment black so u dont affect your lighting solution. On you white object, click on vray properties and turn off the GI variables so it doesnt affect the scenes lighting.

 

But the Alpha should do the job.

 

Another idea is to use that element as a specific channel to deal with in post.

[rmccoy]

There are a lot of ways of saving our your alpha with an image. I typically save my files as a targa (.tga) file as a 32-bit file with a pre-multiplied alpha. once in photoshop you and choose the menu bar - Select - Load Selection - and then choose the aplha from the drop down list. make your image layer editable and then delete the background.

 

That should solve your background issues. The above posts will help your lighting issues