Renderpass opton "ADD"... ?

[tom schuelke]

Well We are doing some Renderings for a virtual Museum.

We use first time the Vray framebuffer to render out also the

"raw GI" pass, and the "Raw light" pass.

Our Clients wish to put into the renderings some Photos of Carpets using Photoshop.

Now i thought, they could use the raw gi pass, and combine it together with the photo to get a good light onto those shopped carpets. if now you put the raw Gi pass on top, (with negative multiply), this would do the job.

Now .... i usualy use German Photoshop.

Who can tell me , which transfermodi in Photoshop is like in Vlados example in the online tutorial, the same as "ADD", .

i cant find anything like this in photoshop..

Tom

[Candelero]

Vlado used PhotoPaint to add the passes, not PhotoShop.

As for the PS - I think <Linear Dodge> does the addition.


Best regards,
nikki Candelero

[tom schuelke]

Thanks Candelero.

Ill try this


Tom

[Da_elf]

isnt AEs ADD the same as the others?

[joconnell]

Yep - ae has a standard add mode whereas photoshop has never had an add mode - quite odd really. A lot of the time I prefer after effects for comositing stills because of reasons like this - plus better grid warping and distortion tools...

P.s. Tom, any time I do multipass rendering to composide something into a live action background, shadows always come out as black shadows on a white ground which are blended using multiply mode so yeah if you use photoshops multiply mode for the shaodws it'll blend nicely.

Another thing to consider though, is if you are adding a dead black shadow over the floor by rendering a non coloured gi and multiplying it on top. you may be better off taking your raw gi pass and using it as a mask for a photoshop adjustment layer - say for example you add a curves adjustment layer over the flat carpet layer and then add a mask to the curves layer. load your raw gi pass into this mask to have the falloff set accurately. now you can use the curves to darken the shadow areas with a lot more control than just putting a black layer over.

Another possibility is to use a hue / saturation adjustment layer. Say for example you have a shadow pass from a sunlight, you could use this layer as a colour correction pass to make the area covered by the sun shadow darker by the appropriate amount, but also tint it a little blue to take into account the ambient skylight that can still leak in.

[tom schuelke]

Hi Thanks you all.