VRay Sun, Sky and Physical Camera video tut + Bonus Script!

[studioDIM]

could anyone please take a little time and sum up all the relevant information on this topic now?

If it looks good, use it. If it doesnt, try changing the numbers a bit.


Thats really all it should ever boil down to.

Lmao, spot on!
But aside from the real goal, the way is that of darkening materials to use a "finer" grain in dealing with the very big sun intensity.
The camera and colormapping help by bringing detail back from the darker areas.
It's easy enough to use the script to mass-change values and see the reaction.

Lele

[DaForce]

cool...
...guys lets make one big thick line here and start from begining? could anyone please take a little time and sum up all the relevant information on this topic now? Lele? Daforce? (i would ..but i got lost myself )

All you really need to worry about is the tuts/videos.
The rest of the thread is Micha and Lele banging rocks together

Anyway, I will let Lele sum up the relevant information (perhaps in point form) as its his tut, and well it would be best spoken from the horses mouth. (no offence Lele :P )

[studioDIM]

Anyway, I will let Lele sum up the relevant information (perhaps in point form) as its his tut, and well it would be best spoken from the horses mouth. (no offence Lele :P )

Wiiii-Hiiii!

Lele

[jacksc02]

what have i missed here?

[DaForce]

CJ!!!!

Your back.. how was your holiday man?

Read thru the whole thread.. pretty hilarious

[studioDIM]

A couple of pictures taken with a phonecam, at midday or thereabout (check the absence of long shadows).
Honest guess, what's gonna be those windows' reflection value?
And the diffuse? Considering we do no post, but mimick the uncorrected pic...


and the opposite side of the courtyard:


Lele

[R_Cyph]

Hey,
Lele, I have gone over your tutorials and I think they work perfectly. Quick question though. Would you say this workflow works for interior that DO NOT have a bright sun as it main source of illumination? Since you are tring to simulate BRDF/BRSF materials, shouldn't this workflow work in any situation so long as you expose properly with the phys cam?

R_cyph

[studioDIM]

Yes, ideally the method *should* work in any context.
The method, mind you, not the values themselves, however.
The 0.255 value is chosen there purely because it works in that particular context.
The "phisicality" of it is not assured in any way other than that of mimicking the perceptual brightness of an object under those strong light intensities, which i think to be a lot darker when prepared than it is when actually perceived.
When working with standard light fixtures, in a largely LDR environment, lights in the first place do not simulate the correct intensity ( i talk of a max standard light), so going about the rest of the scene without one fixed reference (in the tutorial case, sun and sky at 1.0 multiplier) means simply one can adjust however he sees fit.
In that case I'd keep going about materials in the old fashion, for the sake of simplicity, and use the vray physcam with exposure turned off, so to avoid the issue entirely.
After all, there's normally no light in a scene with a 300 odd multiplier and no decay to care for, is there?
The physcam can however be used to expose, but i think you'll find it easier to use when in a very HDR scene, rather than in LDR ones.
Exposing a scene with low dynamic range lights might result in a perceivable loss of contrast.
And most of the exposure can be obtained, for implicitly LDR scenes, with the vray VFB or a post software and HDR imagery.
In the case of a sunlit scene, that would prove hardly viable to do in post: sure the colours would be brought back in range, but not exposing the scene with a sun at 1 would simply lead to perfectly white renders, fairly hard to work with

Hope i answered,

Lele

[R_Cyph]

Thanks!
That really clears things up for me I may still do a test or 2 with your method with a LDR scene and compare it to a scene with stardard material methods. I'm interested to see this "loss of contrast" and how it affects the overall image. Again thanks for the great TUT.

[glorybound]

Simplify

Not to simplify things to much, is it safe to say that if I have a white box in my exterior scene that has a r,g,b of 255,255,255 and a float point of almost 1,1,1, I am almost perfectly exposed? I have tried almost everything and nothing in itself seems to work. Combining several methods seem to work for me.

I need colors to work... a Benjamin Moore HC-100 has to look like a Benjamin Moore HC-100, if you know what I mean.

I am using LWF, color correction, and I am dividing my highest float point into my ISO and voilà

[studioDIM]

Err, sorry I missed your post, Bobby.

There is no difference whatsoever, in principle, between doing what you do and doing what the tutorial shows.
The moment you expose, you change the colours.
Working as the tutorial shows, however has some side benefits, at the expense of a bit more setup work.
Your Benjamin Moore HC-100 will look itself whether you render it without exposure and with traditional lighting, or you expose, cut it to a quarter and use sun and sky.
What matters is the rendered pixel colour.

Lele

[glorybound]

Color

Thanks for the reply. For the first time I made our interior designer happy. Color has always been and issue, but this last project we didn't have any color issues using your method.

[studioDIM]

Aaaaah, nice to hear it helped bits, Bobby.
Thanks for the kind words

Lele

[flavrsaver]

I've never used DepositFiles before and I'm trying to download the scene that Lele posted on the first page. Do I have to sign up to use this service? I've tried clicking on the "Download" button on the "Free" column, but it just launches 2 windows and I can't see where I actually download the file.

[studioDIM]

Eh, i see what you mean.
It goes like this here: click on the link, click on the free column button,wait for the counter to get to 0 (mid-bottom right of the new depositfiles.com window that opens up), and click on one of the FREE mirrors (i used mooload in this case, but it may well vary by country).
Normally, there's more adverts, a mess of links, but also the proper link for the download.
Mooload has it at the bottom, well centered in the page.

http://www.mooload.com/new/file.php?...hyscam_tut.rar

Try if this link works at all (you'll have to click the download link at the bottom anyway, i guess that's randomly generated).
It didn't work like this when i first uploaded it, but i guess it generated enough traffic to be spread around.
I'd love to hear from someone with BW to spare to host it, in case.

Hope it helps.

Lele