multiplier theory

[vizuals]

I've been making lots of interior 3D's lately
And to create a lightfull image I crank up the receive GI in v-ray property from 1 to 1,3-1,7. (except for thing on the outside)

This usually creates perfect lighting situations for me, though I never read anything about this technique in any of the topics I've read.

I was wondering if there was anyone else doing this, and if there is a down-side to it all.


greeting
Leon

[cpnichols]

It sounds to me that you are trying to get the scene "brighter." This is probably because you don't have enough light in your scene, or you are not using the proper LWF. Either way, increasing the receive GI does not sound like a good idea at all, as changing the "physics" of how lighting works generally is a bad idea.

[priad]

Could you post some pict made with this technic ?

[vizuals]

Indeed I use this technique to increase the brightness, and yes it is not a natural way, but changing the
"dark multiplier" (in color mapping) isn't natural either.
I like to think of it as, longer exposure time with a camera.

Here is the comparison, without and with

[jacksc02]

the ceiling has some bad GI in the second image, I wonder if this is due to low settings or your changing of the properites of the objects

[vizuals]

it is because of bad render settings

fast rendertimes, shitty GI

[cpnichols]

It looks to me exactly like I said. You are not using a proper LWF and are trying to correct it with the GI multiplier. Basically the room lighting looks way off to me. Th ceiling looks self illuminated... because it is. Following a proper LWF would allow you not to resort to such measures, and may actually even decrease your render times.

[vizuals]

okay, seems resonable
worth a try, at least

What do you think I should add or change.

Now I have a direct spot 0,7 , and GI environmental override 0,7
(and some local spots with maximum range)
And colormapping dark 1,5 - light 0,9

(LWF is an unknown term to me)

thanx for c&c

[percydaman]

all those numbers you just gave, become kind of meaningless when you switch to a pure LWF method, as they would most likely need to be changed. As to the LWF itself, start doing some forum searches and set aside some time for some reading. lol

[cpnichols]

There are about a million threads all over the internet on the subject...

Like this one right next to your thread:
http://www.chaosgroup.com/forum/phpB...ic.php?t=17356

But a better one is this:
http://www.chaosgroup.com/forum/phpB...ic.php?t=15303

Things to keep in mind:

Your lights will need to be darker
Your shaders will need to be darker

If you look at image without the proper sRGB lut on, it should look dark, very contrasty, and saturated. When the sRGB lut (approx 2.2 gamma), it will be perfect.

Best way to test it is with a vraycam, vray sun, and vraysky, since these are set up for linear.

[m_hinks]

hey Chris,

Ive just finished the second of your dvd's. They are v good. Have learnt a lot, and am trying to use LWF as my thread you pointed to shows.

Has your method of setting up a LWF changed from your dvd now the button for srgb has been added? Do you set the preferences so your bitmaps has 2.2 added to them for example, as i didnt notice you doing that in the dvd?

Thanks

[cpnichols]

hey Chris,

Ive just finished the second of your dvd's. They are v good. Have learnt a lot, and am trying to use LWF as my thread you pointed to shows.

Has your method of setting up a LWF changed from your dvd now the button for srgb has been added? Do you set the preferences so your bitmaps has 2.2 added to them for example, as i didnt notice you doing that in the dvd?

Thanks

It depends on how you work. If you paint your textures linearly (I did), then you want your gamma read to be linear too, meaning 1.0 gamma. If you want to paint your textures in a "standard" way with the monitor gamma burned in, a 2.2 gamma on the read is the the way to go.

The sRGB button was not available on the version of Vray I was using. The only thing it offers is not having to put that curve thing in.

[vizuals]

Thanx percydaman for the wake-up

And thanx percy for the given threads, makes me very confused, as it did a lot of people. Got to test and find a routine.

Cant read all the threads, wouldnt have a life left.

[vizuals]

Just a question to you, cpnichols

You say to use vraycam, vraysun, and vraysky

Is using the "GI dark, GI light multiplier" still nessecary, or obsolete with lWF-m3 setting like Vlado said ???

Or environment override for that matter??

For the next picture I changed:
- gamma on monitor (lcd) to 1.0
- got rid off spots, entered vraysun and vraysky
- environment overrride off
- GI dark/light to 1/1
- used a vray cam



Looks natural but still like a dark tunnel
and the sky color is really dark (found more threads on that one)

any more help is much appreciated
I like the learning

[ene.xis]

set the gamma in the color correction roll out to 2.2
re adjust ur camera
and play some more with the color mapping

what do u mean by "GI dark/light to 1/1"?