Vray vs Maxwell - test for my future renderer

[pshupe68]

sea2stars - wow - those look awesome. Thanks for that. I think I might try a night shot and see how those look with no other lights on.

I'm having some difficulty with the vray2sidedmtl to get them to look like the link you posted? Is there a tutorial somewhere? Or if anyone would like to enlighten me, so to speak. I would appreciate it greatly. Thanks.

Cheers Peter

[pshupe68]

Updated image - I was side tracked for a while but got some time to tweak a few things. I am still struggling with the vray2sided material - the lights look a little blown out with no effect in lighting on the wall closest?? - that seems strange. I will post a blowup with settings to get some advice

another thing - how do I output an alpha map so I can put a background image outside the windows and behind the blinds? I have tried tga and tiff with alpha selected but get all white images in the alpha channel. Please advise. Thanks.

Regards Peter.

[^Lele^]

Make sure you have "affect shadows" on in your transparent mats, and for GI make sure "refractive caustics" are on.
Edit: i should have said "Affect Alpha" in the materials, but there you go...

[pshupe68]

LeLe - I checked "affect shadows" with no noticeable change. The other settings under GI was on. I didn't change any of the defaults.


I find it strange that the lamp shade is blown out but there is no bright spot on the wood which is very close.

I am attaching my settings for the vray2sidedmtl. I tried to mimic the vague description from the help. I used a pure white jpg in the duffuse slot under the VrayMtl that is Front material slot of the Vray2sidedMtl?? I also put a noise map in the Output map slot, with default settings. The shade material doesn't look too bad but they are quite blown out, they almost look completely white - I will attach a couple with varying intensity of light inside. - Please advise.





Another quick question - I am having trouble developing the alpha map?? I have tried tiff and tga with most of the combinations and they have always come out with a pure white alpha channel?? Is that because of the Vrayglass material? Shouldn't it give me a bit of a slightly opaque layer to put my background behind??

Thanks a lot for all the help. The image is really coming along. Next will be the brushed aluminum and stainless steel materials - Just a heads up - Thanks again.

Regards Peter.

[jacksc02]

looking good mr Shupe!
With the alpha problem make sure the glass has "affect alpha" check in the material

[pshupe68]

Thank you Mr Jackson! I must have to stay up until all hours of the evening working on renders to remember all this stuff?? Or get less aluminium in my diet! ha I may just be getting too old for this stuff!

That seems to work but now the alpha channel does not include the slightly opaque blind or the reflections on the glass? Am I missing something? I'm sure there is a way to have the alpha selection show semi-transparent objects like the blinds and reflections, no?? Please advise. Thanks again for all the help.



Any input on the vray2sidedmtl? I would like it to be a little more opaque with a more diffuse glow. See attached. I might try a little darker material for the shade. Any insight would be greatly appreciated.


Cheers Peter.

[pshupe68]

Alpha channel problem???? Does anyone know how to fix this or a work around? Is there a way to place the background image somewhere and have it render? I guess I could map it to a plane and adjust, but it seems kind of finiky. Especially considering I have the image the right aspect and size ready to go behind the alpha channel. Please, if anyone has any advice, it would be greatly appreciated. Thanks.

Cheers Peter.

[vlado]

For glass, you'd need to select the "Affect alpha" option for the glass material.

Best regards,
Vlado

[sea2stars]

Would he also have to check the Affect Alpha option under his blind material also?

It might just be easier to throw your background image into an environment/background slot.

[pshupe68]

vlado & sea2stars - thanks - a couple of posts up jacksc02 mentioned that and the images after that reflect that change. I have the alpha split showing up but no semi-transparent objects are illustrated in the alpha channel. I am testing with adjusting the refract colour from 255, for glass, and 0, for the blinds. I tried 10 difference in both aspects but no dice. I will try higher values to see if that helps.

sea2stars - I am using Vray 1.50 with a vraysky in the environment slot. If I put my background in there, won't I lose my environment lighting? Is there another area to add a background image??

Thanks for the help.

Regards Peter.

[rivoli]

as long as alpha goes, if affect alpha doesn't work, you may try going in the vray properties of the blind objects and set the alpha contribution to whatever value works best. like if they had to be half opaque, 0,5 would do the trick.

[sea2stars]

Well.. there's the V-Ray::Environment that'll override the sky in Max and provide the actual light, but you can still put whatever you like into the Environment map under Rendering - Environment on the main menu bar in Max; Vray sticks a VraySky map there so you'll actually see it when you render. You'll also need to set the map texture coordinates to Environ and mapping to Screen, but I'm pretty sure that'll do it automatically once your pick a bitmap to use in that slot.

Or you could map it to geometry behind the windows, but that adds a few more steps so it won't cast a shadow, won't block the light, won't be visible to GI... etc.

[LQ2]

Alpha Channel and reflection...

Hi,

I thought I'd make some comments on the Alpha channel issue, and the lack of reflections on the Alpha channel.

I am not sure that the reflections should, or will be, present on the alpha channel, but I would always solve that issue by rendering a reflection pass at render time anyway, then edit them post. In V-ray 1.5 this is really easy, you just select "VRayReflectionFilter" in the render elements tab. The reneder elements is a really great feature of VRay.

With respect to the blind alpha, it's jsut to do with the material applied to the blind as it has already been pointed out. You'll need affect alpha on, and make sure that there is refraction on the material, i.e. not black colour, or a refraction map that is not black.

You might also have to consider the number of layers of transparency that are considered in the final render. Perhaps you have lowered the number of layers of transparency to speed up render times and thus stopped VRay showing the transparency?

Anyway, I hope these are useful and not too much rubbish.

Cheers,

[pshupe68]

Thanks for the responses - no luck with the alpha channels

LQ2 - I tried the reflection pass and it seemed to output the same as the alpha. Not sure why.

I have been swamped with other projects, so I apologize for the delayed response. I will look into the suggestions a little more when I get the chance. I really appreciate all the feedback.

I might just make up some selections in PS and add a reflection pass, which would mean just cranking up the reflection of the glass and making a layer with slight opacity. Sometimes faking it is just easier. Thanks again and I will continue to post as I need more help.

Cheers Peter.