Jeff Patton JeffPatton Location: Lexington, USA Language(s):
English Member Since: August 2002 Last Updated: 29 June 2008 Portfolio Views: 484640 Chosen as Favorite: 303
That's the exact scene minus the chairs, floor texture map, and DOF. The light/exposure settings are exactly what I used. So why does this version have more blue light? Simple...The chairs are/were red, therefore they bounced red/warm colors into the room. The floor texture which I could not freely provide was a "warm" colored wood which also provided red/orange bounced light into the room (and gave a warm feel to the room).
hey jeff thanks for explanation. I understood it now. one more question, also when you capture the chrome sphere, do you take photographs with different exposures or you just take it once as in production shaders low dynamic jpg images work great too.
It was just single exposure .jpg's. One photo for use as the background image and one closeup photo of the chrome sphere for reflections & illumination.
I just had a small breaktrough with my plush material using a fresnel falloff map in the diffuse map.
I'm making a realistic interior and I have a quick question about white balance. I have a room with one light in the ceiling, 3000K, and a window on one wall to allow bounced sun- & skylight into the scene. I'm unsure where to put my whitepoint.
I can easily adjust it to something I like (have it at 5000K now - gives me a nice blue light from the sky, but also a warm glow from the ceiling light), but I'm wondering if there's a "correct" setting for the whitepoint in such a scene? By correct I mean what maybe a photographer would use if he were to take pictures of the interior or what our eyes would see if we were standing in the room.
Good question. I'm just getting started in the world of photography so I'm not sure if there's a rule of thumb for that scenario. I'd think that would lead into a gray area where it comes down to artist preference...but who knows, maybe there is a guideline. As time allows I'll keep digging through some photography websites/books and see if I can find a rule for that scenario.
And for what it's worth (and reference) my digital camera has these presets:
Daylight = 5200k
Shade = 7000k
Cloudy = 6000k
Tungsten = 3200k
White Fluorescent light = 4000k
AWB (auto)
Flash
Custom
hi jeff, i've just been experimenting with caustics in your kelvin temp example scene, where you have two sky portals acting as visible area lights. is there anyway of incoporating hdri into this scene. the only way i know of using hdri so far is by adding a hdr image to the environment map slot, then instancing this into the material editor (changing a few settings along the way) and then instancing this into the sky colour of a skylight. so can hdr be incorporated into the scene with the sky portals rather than a skylight???
sorry jeff, my bad, i've done it now, i was being really really slow
i just used exactly the same process as the skylight, but skipped the bit for where i instance the map into the skylight 'sky colour slot'. i also unchecked visible to renderer on the sky portals and it seems to work fine
sorry just been playing with MR lots today, however, i have come across a problem when trying to animate an objects visibility.
i want a gradual transition from completely invisible to fully opaque.
however i believe mental ray doesn't support object visibility.
is there a workaround for this
i have attempted the effect with a blend material and then animating the mix amount from 0 to 100. this works on the object, however i am still gettin shadows when the object is completely invisible.
i am going to try one more thing and that is to animate the 'cutout' slot in an arch and design material from a solid black colour to a white colour via the use of a gradient, hopefully this will work.
if you think of any workarounds then please let me know
Right, the visibility track can't be animated with mental ray (it's either on or off). It's a common complaint and believe me when I say that Autodesk is aware of this issue. The only way around it that I know is to do exactly what you're doing...animate materials locally.
thanks for the response jeff, i have rendered out two animations, one is using standard materials and animating the mix amount on the blend materials. The other is the same process on ana arch and design material and animating from black to white in the cutout slot.
both animations have the same problem, and the area where the object (teapot in this case) lies on the ground plane, is still visible when the teapot is meant to be fully invisible.
is there somewhere i could upload these animations too so that you could take a look at what i mean???
i will try and upload them to my blog and create a blog entry detailing what i've done and errors that have occurred (i guess this would be useful for others as traffic starts to hit my blog
