The rendering assessment, required us to do two separate lighting scenarios. Here are two images (both are not mine) oh lighting scenarios I liked the feel of, the first is an early morning or late afternoon sort of feel, which if I had time I would have liked to play around with light fog and bokeh lighting effects. This scene has a more natural feeling to the light, it’s quite warm and inviting.
The second lighting scenario is a cooler more artificial light kind of feel. I also like the style of the kitchen in this image and that the cool light is broken up briefly with a warmer light along the top of the bench.
Here are my initial lighting setups; The first one I decided to use the physical sun and sky node within the render settings, I felt this might give me a more natural “early morning” feeling and the sky reflection on the tiles if incase it was to be seen in the final render. I also used an area light to the left of the scene to fake the light on the fruit bowl a bit better as the physical sun and sky wasn’t doing the best job at lighting up the room. There is also another area light to the right of the camera to help soften the shadows.
Here is the second lighting scenarios, initial setup. I only used two lights in this scene, an area light up near the ceiling to replicate the blue, cold, artificial light and a second area light with a sphere light shape on it directly above to imitate the warmer artificial light.
This time round with my pipeline I decided to wait with turning on the photons option until actual textures were on the objects. All of the fruit, minus the grapes were textured in Mudbox, the grapes however were procedurally textured inside Maya using a custom Python script from one of the teachers to create a shader network which flowed through a ramp to randomize the colour of the grapes by only using a single node to control this.
However this shader network connects to a lambert which doesn’t hold the attributes needed to create sub surface scattering (SSS) or control the glossiness. To correct this I needed to plug in the following shaders into the randomized network. The ramp plugs into a misss_fast_shader which controls the SSS, while a mia_material_x shader plugs into the diffuse of the misss. This now gives me more control of the actual fruits texture, I also plugged a mountain texture into the colour on the mia shader to replicate the little brown spots on the grapes. I had to make sure the snow attribute was turned down to a mid grey to keep the green colours from the ramp from washing out.
I decided with all the fruit textures I wasn’t going to tough the roughness attribute as I found this made the “natural” shadows originally cast by the light dull and lifeless. For the other fruit I only really concerned myself with the reflection, glossiness and gloss sample nodes, as well as plugging in the bump and displacement maps.
For the wall tiles I used a marble texture I made earlier in the year and created a bump map using noise to give the tiles a bit more of a texture. The bench top is a procedural texture, consisting of a fractal for the colour and pattern with a noise in the bump map. The fruit bowl itself is a free texture from CGtextures.
Now that I have the textures in place, I can start to readjust the lights and finally add in the photons, final gather, and global illumination. I found working this way was a lot faster and more efficient than the last rendering assessment. I remembered to use light linking this time, and it was crucial I used it on the grapes in the first scene as the python script shader doesn’t respond well to the physical light and sky node, a third light had to be made just to light the grapes, this was another area light with quadratic decay and photons.
The rest of the scene was mainly lit with the physical sun and sky, where I adjusted some of the settings like I upped the Haze to 0.500 so the light had a more diffused “morning” feel to it, turned on the photons as well as finding how to change the quality of the shadows took some time to find as I originally thought I might find these in the render settings, however it is hiding on the second node created by the physical sun and sky button. Here I ramped the shadow samples up to 64 and changed the softness of the shadows from 1.000 to 10.000 this then gave me the final result you see below.
I also adding in some depth of field to the camera, with an F stop of 2 and the focus region scale also at 2.000, this softened the background just enough to keep the viewers attention more on the fruit rather than the background.
For the second lighting scene adjustments, I imported the lights from the second file into the first so I could save some time with the settings of the textures. The only real adjustments I had to make here were to make sure the light above, the intensity was high enough to light the scene but low enough to not blow out the SSS on the grapes as I found when I went too high the top few grapes would turn a blueish grey. The other thing I changed was the intensity of the blue light and used it more as a atmospheric fill light, leaving the bulk of the light to come from the area light above, which also has the photons turned on.
Final touches included the rotation of the camera view and adjustment of the depth of field attributes (only the distance as the F stop and focal region scale remained the same).
This term for TAFE I have my final rendering assessment. An add on from the first assessment of the banana and apple, this time it is a fruit bowl, containing; grapes, an orange, a green and a red apple, some pears and a bunch of bananas.
Below is a bunch of photos I took (not the best) as R’n’D for the assessment, this way I can document the surface properties of the fruit and keep that in mind when manipulating the Mental Ray shaders in Maya.
For the grapes, I knew prior to getting the assessment that we would need to use sub surface scattering within the shader network. A few other things I have noticed is the skin is partially transparent and that grapes are made up mostly of juice/water. So I feel to get my sub surface scattering to work more realistically, and not have my grapes ending up looking too plastic, I will need to change the index of refraction value to 1.33
I have also noticed that there is quite a distinct hot spot in places that is also, when it grows larger becomes rougher around the edges. Brown speckles are also quite common on each individual grape.
The red apple is more vibrant than the green apple, with a more variant range of colours from red, yellow, orange, green and brown. Pores on the apples skin tend to be raised instead of dimpled. Any cuts or pierced parts of the skin turn a dark brown in colour. The hot spot on the red apple is also a bit more noticeable than the green apple.
The green apple has less of a colour range than the red apple. Its colours range from greens, whites, yellows and browns. Like the red apple the pores tend to extrude rather than intrude.
The pear, like the red apple has quite a range of colour in the skin, the pores are the most distinct being brown in colour and intruding slightly into the skin. Pears have the most interesting stalk of this bunch of fruit, its twisting form is quite wrinkled and has deep crevasses.
Oranges have the hottest and sharpest of the hotspots, the skin is the most evidently riveted and ever so slightly transparent.
The banana is the most diffuse of the fruit, it still however has a hotspot, but due to the matte-ness of the skin the light is absorbed more. The skin of the banana is not perfectly smooth, but however has a sort of corrugated texture to the skin.
More work on this today in Autodesks Mudbox
Today we looked at the paint tool, stamps and stencils, normal maps and dirt maps.
Here is what I ended up with, I think I may have gone a little crazy on the texturing…
Here is what I did last week, using the stock tree stump in Mudbox, we learnt how to using the sculpting tools and how the layers whilst using the levels work, to build up a sculpt.
Here is my final result, this is a jpeg file so the quality is not as great as the final TiFF.
My reflection for this assessment, I don’t think I got the color bleed down pat, I can get it to bounce off the fruit onto the other fruit, however I cannot see much on the floor.
I need to figure out how to completely smooth out my lights, as I feel both the shadows and light (the secondary lights not so much the key light) are still to grainy.
The scene is, I feel, a bit too bright over all I could decrease the brightness of the key a little more.
Next time I will also change the way I go about the pipeline as I felt it was always one step forward two steps back. For instance next time I would set my lights and photons/ final gather once the textures are on the objects, this way I won’t have to back track so much.
My last thought would be, that I need to watch the placement of my lights with high shine objects, I wanted to use barn doors on some of the secondary lights but I just couldn’t get them to work. Also I feel that the objects not being life size was also an issue with the lights.
These are just a few things to keep in mind for my fruit bowl assessment.
Having now added my mia_material_x to my fruit and the color, gamma and bump maps are in place on the shader, I feel my lights could be better as I have a lot of highlights on my apple that I feel shouldn’t be there if it was to be a realistic set up.
So I decided to remove a few of the lights, the apple kicker and rim lights were removed as well as the banana rim light. I added high samples to all the lights to 8 x 8 to try and get rid of some of the graininess from the lights ( I don’t think I did this very well.) I scaled the key and fill lights as well, the key mainly to get the shadow wrap around and fall off feel more natural, and the fill to try and soften the highlight on the apple that was accruing.
Also playing around with the photon count to smooth out the bounce of color onto the other fruit.
Here is a snap shot of my final light set up.
The UV maps were already pre made for us within out Maya scenes, so saving out the UV’s as an .iff file to use in photoshop. Using multiple layers in photoshop to build up my textures, like in previous posts, but I try not to spend too much time here as this part isn’t assessable for this assignment. Here are both my color and bump maps for the apple and the banana.
I tried to replicate what I saw on the fruit in my real life studies in post; https://madhatterstatic.wordpress.com/2014/04/12/reference-for-rendering-assessment/making sure I made the pores on the apple white so they became extruded slightly when the bump map was applied to the model. Other things I was keeping aware while creating my texture and bump map was the stringy texture on the banana the inverted and extruding pores, and the fact that either fruit is never completely smooth. The bump map is a grey scale version of the color texture, that has been inverted and the levels adjusted to the right tonal values I wanted afterwards.
And here is how it looks in scene.
Instead of using Lamberts, I am now using Mental Ray shaders on my apple and banana. The shader I am using for this, is the mia_material_x, with this shader I can control the:
- index of refraction
To name a few.
I found that at first I wasn’t getting much in the way of speculars, especially on the apple. Going through the attributes of the mia shader, I found I had metal material ticked on and once I unticked this property and the highlights started working how I wanted them to.
I feel the highlight on the banana could be a little more. However the shape of the banana doesn’t help much for catching the light.
The highlights were controlled by keeping the glossiness at 1.000 and just played with the reflectivity. Also played with the weight and roughness, which I feel could be part the reason why my photons and final gather, color bleed didn’t turn out so well once the textures were put on the fruit.
The bump maps (shown above) were plugged into the Mia_material_x shader bump attribute in the overall bump attribute using a file node and the colored texture (also shown above) was plugged in the same way using the color attribute of the shader.
I think the fact I played with the diffuse on the shaders once the textures and bump maps were on the fruit, affected my photons and final gather output. I should have just left this alone, I also feel that I added in the photons and final gather in at the wrong time in my pipeline, which I think cost me my color bleed in the final render.