[bjorn.syse]

Hi,

When I render with Alpha, the background is premultiplied black. I forgot the reason for this. But, could it theoretically be white instead? or an option?

It seems I more often need images layed bare on a white background than on a black one, and that would spare me some tedious photoshopping.

Regards,

- Björn

[zdeno]

remove black matte - all photoshoping

[devista]

http://think.maxwellrender.com/-110.html

saludos
luis

[bjorn.syse]

Thanks guys, but I know all about that. What I'm asking is more of a wish. Could the render channel come premultiplied with white instead of black, or are there something technical that prevents that from beeing feasible?

- BJörn

[brodie_geers]

I seem to recall Tom dealing with this issue some time ago. As I recall, he didn't say that it couldn't be done but was extremely hesitant about doing it. Presumably because the black background provides the best ability to be cut out while preserving antialiasing (assuming you've got photoshop set up right which by default it isn't ( http://maxwellrender.com/forum/viewtopi ... a&start=15 ).

I suspect you'd have to give a pretty strong case for adding it into the program as having more than one option could cause confusion for new users.

-Brodie

[bjorn.syse]

Hi

Yes, I remember I've read some thread about this a while ago. Looking at the image in a post by Tom in that very thread you mentioned:



As the alpha channel is black where to cut, and the render channel is aswell - is this the reason you say it has the best ability to be cut away while preserving the antialiasing?

About the confusion, don't you think not having to go through photoshop, dealing with layer masks or other "removal of black mattes" settings at all would be less a cause for confusion for new users? At least in the case where you want your render placed on a white background. This is probably the case more often than that you want a black background, no?

- Björn

[Mihai]

It wouldn't be any different really, you would still have to remove white matte in most cases. It's just the very basic way of working with alphas, it's "standard" knowledge so to speak. But what is the tedious Photoshopping for you? Maybe you're doing something unnecessary when working with alphas.

[bjorn.syse]

No, what I mean by tedious is just having to edit my pictures at all. If it was white, I suppose I wouldn't have to remove any white matte would I?

- Björn

[tom]

If it was white, I suppose I wouldn't have to remove any white matte would I?

Why do you need alpha to make your background white? You can switch to IBL and set a white background image.

[bjorn.syse]

That's true though.. hmm. I guess I don't need it, it just teased me that is was black sinced it seemed so unpractical.

But definately, a white background is not such a bad idea at all. Far to simple for me to notice