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
Usually you add all the light select elements to recreate the direct lighting of your scene.
Best regards,
Valdo
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
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
So it only works with pdplayer or maybe after effects? Is that what you are saying?
no, he is saying for what you want to do, you need a different trick
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
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.
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.
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.
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?
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?
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
I have never tried it, but here is a tutorial for vray composition in photoshop
brilliant!!, ive been looking for something like that for ages. now all i need is a script to do the arranging… because im lazy.. preferably for aftereffects 
that tutorial should also give an idea to the original poster how lightselect might be used 
With MAX 2012 Subscription Ken said that by end of September you can download the subscrition advantage pack which will include a 32 bit layered psd file saver which will also save all your elements
I think you mixed that 32-bit PSD part up with the psd-manager 3 announcement. Atleast on the Area, Ken Pimentel has not said that the Subscription Pack feature will be anything more then 8-bit.
But there is a problem with LightSelect element.
It doesn’t calculate GI seperately. GI is derived from all lights while direct lighting is seperate only.
more like a limitation of vray than a problem with the element, it does what it was intended to do, but not what people were hoping. as i understand it, doing seperate gi calcs for each light would require a lot of reworking if the gi engines in vray.
only current option is to do renders with each light enabled alone, and then comp if you want to mix.