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

[m_hinks]

im simply load my bitmaps, set my colour with gamma set, and expose the scene with vray cam sun and sky. It all works a treat.

[FlytE]

so do u colors if ur setting max to.
..the all point bout the .255 workflow is to darken ur materials so that all the combo vraysky+vraysun+vraycamera works in a predictable way...(please correct me if i m wrong! )

The automatic setting of the maps to 2.2 is only to pull there gamma back to the same level as everything else. However you still need to adjust (darken) them in accordance to the brightness (angle) of the vray sun.

If its just a plain coloured material then you use a vraycolour map in the diffuse slot to adjust it to .255. If you already have a bitmap in the diffuse slot then in the bitmap's 'output' rollout you can change the rgb to 0.255.

[ene.xis]

<edit>
what he said

i m glad it works for u, i mean thats the all point anyways...

[glorybound]

Batty

I am going batty reading these threads. I am assuming v-ray's official stance is you don't need to darken your materials if you are using the v-ray sun/sky/cam. I tried 100's of ways and I do believe you can get good results if you darken your materials, but it is a lot of work and I have had just as good results using hdri's and a soure light as explained in the "Gnomon - Global Illumination Exterior" DVD's.

[^Lele^]

I am not sure about the VRay's official stance, but the tutorial was reviewd by Vlado before being released.
This said, it always seemed to me as if VRay was a set of tools to be used however one saw fit and however it worked for each and everyone.
http://www.chaosgroup.com/forum/phpB...=139470#139470
this is the post that sparked the method, and following tutorial.
This particularly:

Like I said, it's all in the materials... Notice the extreme color bleeding in Dynedain's images, and its lack in the photos. This is not because V-Ray calculates color bleeding wrong or because there is something wrong with the physical camera, but because the actual materials in the real life are much less reflective (e.g. darker).

Best regards,
Vlado

[glorybound]

Exposure Meter

kudos to you for the exposure meter. Question.... My max preview is washed out because of gamma 2.2. When I set max's gamma to 1 then it comes into exposure. Should I just keep my max gamma at 1 since I use the vray frame buffer and gamma 2.2 in max?

[Infrared digital]

I must admit to getting close to understanding this fully but, would someone mind checking my settings so that I am not missing something fundamental ?

Thanks

N















The final image is the outputted render which I think looks fine.

[^Lele^]

Spot on, aye, afaik.

As for the washing out, try the settings in the post above and see if it corrects it.
If not, it may just be another issue.
A couple of images to see what happens would be stirling...

[GVC1123]

New VRSun?

Apparently the VRay Sun / Sky has been changed and updated in the final 1.5 version. If this is ture, and if so how does it affect the methods suggested here?

[GVC1123]

...I'm assuming the .255 color multiplier is no longer needed, that's what I can gather from testing.

[werticus]

yeah .255 with the new sky in an outdoor scene will blow out the image, which you can fix by not using .255 or by using .333 on the sky's brightness, which is a double fix really

i wouldn't suggest im an expert on the subject though.

[aaron-cds]

Maybe I need to experiment more, but I've found that if I change .255 to .3 I get the similar sky as I did in rc3. I also change my physical camera to get 1.0 in the float value. I did a test with the inverse gamma .4545 method in 1.50.00 and it was slower than my modified Lele's method. For me, I think the Lele method is still the way to go.

[GVC1123]

new VRay Settings?

Okay, correct me if I'm wrong, but the new "fixed" VRay Sun/Sky/Camera setup is intended to avoid changing all the scene materials....? That's the idea I got.

Also, if you throw a Vray Sun, Sky and Camera into a scene, all with default values...the render comes out failry accurate and lit (this is with the final VRay 1.5).

However, I wasn't satisfied with that, I like the gamma correction (as mentioned earlier). That required me to adjust the camera exposure to compensate, but that was all. Is anyone else getting this with the new Sun/Sky?

[aaron-cds]

All I know is the Lele method still is 20% faster than the inverse gamma method.

[^Lele^]

In general, the method still works.
NOT the .255 value, obviously, as three things changed: sun, sky and physcam exposure.
The method, however, IS faster due to a faster light decay, and it keeps behaving as expected: lower the diffuse coefficient to speed up the rendering and increase contrast, raise it up to 1.0 to wash the image out more.
Some testing shows that with a 2.2 gamma, and the new models, a value of .4 - .6 work quite well for exteriors.
Do NOT take my word for it though

Lele