Camera mapped background??

[phoenix4]

Hi Everyone,

I am experimenting with matchmoving.

Ok, following tutorials on the web I had to use Mental ray, as I could use the Matte/Shadow/Reflection material, and put my environment image sequence into the Camera mapped background slot so I could have my ground plane appear as part of the background/environment during the animation.

I haven't work out how to do this with Vray.

Can anyone help?

Thanks,
Adam

(http://www.youtube.com/watch?v=UCbrr...eature=related) 3:50
(Using the Mental Ray material in question)

[simmsimaging]

You can use a camera map modifier on the ground plane and apply the background images through a vray light material. If you want it to catch shadows you will need to use a blend material or just a normal Vray material though. That is one way at least, there are likely others.

B

[vlado]

There is also the camera map per pixel texture map...

Best regards,
Vlado

[phoenix4]

Hi,

Thanks for the suggestions..

It is sort of working, but I am a long way off.

- I put the camera map per pixel map in the background env map slot
- put a camera map modifier on my ground plane
- I made a vraylight material for my ground plane.. that worked, but (as mentioned above) receives no shadows.
Adding this to a blend material or using a vray material instead, caused my ground plane to be darker than my environment, so the edges of it don't match seamlessly with the background. It did receive shadows tho.

- Another thing, when I used MR, i used a MR switcher in the environment map slot so my materials on my object in the scene wouldn't appear 'transparent'.

I Hope your know what I mean, as it is kinda hard to describe in this post.
But I am sure may people have done this kind of thing before.

Any more suggestions as to how I can correct my problem I am having?

Does anyone know if there are any Vray tutorials around for this too, which may also help me.

Thanks,
Adam


I found that if I enable Matte & shadows for the vray properties of the groundplane. Only shadows show up.
now I need to work out how to deal with the 'transparent materials'/swticher replacement

Thanks

[simmsimaging]

The reason I suggested the camera map modifier instead of the map type is that the modifier works with RT, and at last check the map didn't

For sure if you only want shadows then making the ground plane into a matte object is the way to go, your original question indicated you wanted the ground to be included in the renders, I took that at face value

For the background thing: if you are just wanting it as a backplate you can try putting a large plane, aligned to camera, behind your scene. Make it at least fill the frame, or larger, and put your Vray light material on that (again with the camera mapped background plate in it, either with the per pixel map or the modifier). Then you can remove the background enviro map and it wont give you that see through problem. The advantage of this route is that the backplate will now also refract properly through transparent materials etc, which doesn't work well with a simple background image for some reason.

Regarding the vraylight material in a blend material: I use this approach once in a while when I do want the backplate to render as well as catch shadows and reflections or caustics etc. You can do it in multiple renders and comp it later of course too, but if you want it in one you need to add the camera mapped image to the diffuse channel of a standard Vray mat and a use that as the coat material in the blend material. Then you need to play with the blend amount to bring the shadow catcher aspect up or down, and to balance out the darkening that happens you bump up the Vray light material intensity. It's not always a perfect match to the original plate, but when you are rendering the plate in the frame it is not likely to matter that much.

Make sense?

[phoenix4]

yes, makes sense.

Thanks very much for your advise, I'll give it a go