Vray lightselect and photoshop

[STUDIO_ARCHITECTS]

Hi all
Can someone please explain to me how to use the lightselect element in photoshop. I understand how to use other elements such as extratex or wirecolor etc. but I am not sure how to use the light select.
In the youtube video he uses the pd player which looks pretty easy but I don't own pd player.
Any help will be greatly appreciated.
Thanks
Reynhardt

[vlado]

Usually you add all the light select elements to recreate the direct lighting of your scene.

Best regards,
Valdo

[STUDIO_ARCHITECTS]

Hi Vlado
Yes I understand that, but what I don't get is this......if I render a scene and lets say one of the lights is too bright and causes a burnt out area on the wall. Then my understanding is that you could use the light select feature to remove that in post production. So I would set up the render element, save it out seperately....but then what exactly do I do with it in photoshop. For instance...if I do a AO pass I would put that on top of my main layer and set it to multiply (layer style) which would only leave the shadow areas, but what to do with the lightselect pass? My main exr is already burnt....how would this remove it?
Regards
Reynhardt

[vlado]

Ah, I see. To be honest I've never used a light select for this particular purpose - perhaps someone else can explain better.

Best regards,
Vlado

[vjaramillo]

So it only works with pdplayer or maybe after effects? Is that what you are saying?

[Morne]

no, he is saying for what you want to do, you need a different trick

[vlado]

So it only works with pdplayer or maybe after effects? Is that what you are saying?

Nope; I was saying that I haven't used the light select element to reduce a burnt out area around a light. I have only used it to adjust the individual contribution of lights to the final image.

Best regards,
Vlado

[devin]

So if you only have Photoshop or After Effects what's the process for combining these elements back into a final image? I can't find anything on it so either no one knows or it's not possable.

[stevesideas]

I'm pretty sure you have to just output each light element to a half float image, exr or HDR and then select "add" mode for each layer. I'm pretty sure thats how it is done in PD player too.

[rayo-v]

......if I render a scene and lets say one of the lights is too bright and causes a burnt out area on the wall. Then my understanding is that you could use the light select feature to remove that in post production. So I would set up the render element, save it out seperately....but then what exactly do I do with it in photoshop.

to achieve that in PS you can use your lightselect layer with a Difference blend mode, that will get rid of that direct light completely. After that can use the layer opacity to "dim" the light if you want.

[TRGraphics]

It appears if I use the add mode in photoshop all you can do is make the light brighter, not lower. Am I doing something wrong or is that all it can do?

[super gnu]

arent you supposed to use the lightselect element in combination with the raw diffuse etc.? not the final rendered image. if you rebuild the image from the correct elements- reflections, gi, diffuse etc.. then you will have all the direct lighting effects separate, to adjust as you wish. never actually used this workflow, so not sure of the blending modes.. id really like to see an example psd with an image built from all the possible render elements, with the correct blending modes, to take a look at. maybe it could be something included with vray?

[super gnu]

on that note, are there licensing reasons against including a psd exporter? it could save out nice layered 32 bit psds with all the layers correctly arranged and blended.

or is this something that theoretically exr can do?

[simmsimaging]

on that note, are there licensing reasons against including a psd exporter? it could save out nice layered 32 bit psds with all the layers correctly arranged and blended.

or is this something that theoretically exr can do?

There is the plugin from Cebas for doing that so perhaps it's just a cost/benefit thing for Chaos. I'd love to see that functionality in Vray too though. Or just a VRIMG plug-in for Photoshop - either way would be a big help.

b

[glorybound]

I have never tried it, but here is a tutorial for vray composition in photoshop

http://cg.tutsplus.com/tutorials/cha...-in-photoshop/