Pipeline and trouble-shooting

I am working in a linear colour space. This is so that I can work with mental ray and see true colours. There are linear settings in render settings. The render view is 32 bit floating point HDR. Mental Ray is plugged in to Maya. Mental ray is enabled in render settings. Enable colour management and sRGB are chosen in the common tab of render settings. On the render viewer the image colour profile is linear sRGB. Quadratic decay is chosen for standard lights. All shaders are mental ray mia material shaders. I chose to render as tiffs for this assignment so that it was easy to see the images straight away.

The resolution is HDR 720 or 1280 x 720 pixels.

My first render is late afternoon. I based it on some of the photos where the light was streaming in from an open door and that was the only light. There are 2 scenes, one has depth of field and is focussed on a banana with the bottle out of focus and the other shows things more clearly. I think they are successful. At first I had a directional light outside but I am having much more success with a physical sun and sky shining in the window. I have used caustics to show light shining through the water bottle and Final Gather to collect the light. There is  a caustics light on just the bottle shining caustics photons. I increased ray tracing and shadow samples to collect as much light and shadow bounces as possible so that it looked more natural in the shadows and bottle. Ambient occlusion is on all the objects shaders so that the shadows gather in corners and crevices and where things are close together.

These are the settings I had for the physical sun and sky and inside lights below. It gave a warm sunsetty glow and the sun shone in through the widow leaving a shadow of the window. The red- blue shift was set at .5 to achieve this, I lowered it a bit to .3 because it seemed to red. The rotate X value of the sun direction was -2.773 to make it shine inside but I changed it to -4.436 to put the shadow in a better place.

I had issues with graininess in the shadows. I increased the UV samples but couldn’t make it better. Getting a physical sun and sky helped, changing the shadow softness on the physical sun to .5 or .8 and increasing the samples to 32 improved the shadows a lot. I did notice that in the shadow the vertical bar on the window got a lot thinner than the horizontal one and the other shadows as I changed the softness setting, but I could not work out how to fix that.

The second light settings are more middle of the day with bright lights inside shining on the fruit, as in another photo.

  • Settings- red-blue shift -1 to be more of a blueish tint light inside lights.
  • rotate X in sun direction was put to -55.72 to be higher in the sky

I tried ambient occlusion settings at a distance of 100 but then I measured how far a pear end was from and apple and it was nearly 4 so I tried different distances from 2 to 5 and liked 5 the most. It has good shadows between objects at this setting. I have put it to 10 on the bananas because they are not getting any on them from each other.

An issue I had was that my grapes were too much like lights and eventually a new subsurface scatter was assigned and I started again. I had thought that the sum of the weight of diffuse and front scatter layers had to equal 1. But it doesn’t and it looks so much better now.

  • The back scatter settings done first with the others off are colour- yellow, weight- .5 (set at the end after the other layers were fixed) radius- 4, depth- 4.
  • Next the front layer was done colour- green, weight- .5, radius 2.
  • It looked pretty good to me but finally the diffuse layer was done, ambient- black, overall colour- white, diffuse colour has the variation of ramp of colours using Vince’s script to share the colours between the grapes, weight- .1.

Another issue is everything seemed too washed out but changing the light intensity didn’t affect that and even in the darker settings the fruit has lost its colour and definition. I put in a physical sun and sky and tweaked the settings so that it looks better.

It seems a lot of my issues stem from using Maya 2014 at home and 2013 at college. I always complained things looked different in class to what it did at home. Vince worked out this was the reason and that 2014 renders with unified sampling which doesn’t need as many samples for a great result. This always means there is no anti-aliasing settings to set.

The caustics light worked well. Then it didn’t when I was ready to do final render, there was hardly any there. I plugged a mib_photon node into the photon window of the shader group for the bench top and then plugged the material into the diffuse part of that too. Suddenly there was too much light. Fiddling with all the settings I had put the photon intensity and caustic photons in the light settings up higher and higher. It wasn’t until I lowered the caustic photons that it started to look better and not such a mass of light on the surface. I could also lower the photon intensity. This was good too because it lessened the render time.

Another thing that went wrong just as I was about to do final render was that the water started casting a heavy shadow on the wall, I couldn’t fix that except by setting it to a preset for water and changing the colour to white and the transparency to 1 and diffuse to 0.


caustics light settings

caustics light settings

caustics light settings

  • intensity 0
  • photon colour fawn like the wall
  • photon intensity 1000000 changed to 100000
  • caustic photons 1000000 changed to 1000

render settings

  • raytracing reflections 16
  • refractions 16
  • max trace depth 32 shadows 16
  • GI on accuracy 500
  • caustics on accuracy 1500
  • photon tracing-  photon reflections 16 photon refractions 16 max photon depth 32
  • GF on accuracy 100

water surfaces

  • advanced refraction- refractive caustic on
  • refraction-index of refraction 1.33, transparency 1, glossiness 1
  • reflection- colour white, reflectivity 1, glossiness 1


  • diffuse all 0
  • reflection white and all 1
  • refraction index of refraction .8, white, all white
  • advanced refraction refractive index on

critical reflection for texturing and rendering

This year 2 subjects we took were rendering and texturing. ‘Texturing (is) the process of applying colours and textures to an object to make it renderable’ (Derakshani, 2011, p 9) Rendering is the process the computer uses to calculate lighting, shadows, shapes of objects and movement and saves it in a sequence of images to produce as realistic a result as you want. (Derakshani, 2011, p 495)

Texturing was good to learn because I had a bit of trouble with it last year. This semester it seemed quite hard to learn what seemed vast amounts of knowledge poured out in the class but that was understandable because we learnt how to use 2 whole new programmes, UV Layout and Mudbox, and there were only about 4 or 5 weeks to get all the knowledge. With both the programmes I felt panicky like it was too hard and I could not do it however with patient help from Eric and lots of practice for the assignments I got quite good at them.

UVLayout is used for UV texture mapping. UV’s create a space to paint textures on models. Texture mapping is putting 2D images on 3D objects to add colour and detail. It is a necessary part of completing a model. (Honn, 2010, p. 573)

UVLayout creates maps easily, with little distortion, which are easy to paint on in Mudbox. It was easy to understand but with the whole programme to learn in 1 lesson it was overwhelming. However there were videos to watch which explained everything and I got the hang of it. UV Layout makes it easy to see where there is distortion by different colours for stretched, pinched and relaxed areas and it has an automatic flattening function. We had to use this progamme to UV map Blobby Boy and I like how much easier than Maya it is to use once you know how. In the end I believe I got good results UV mapping Blobby and there was not much stretching on the whole map,very  little blue or red shading on him.

The other texturing programme we learnt was Mudbox, a programme for sculpting and painting an object.  It is good for painting the UV map while it is still geometry so that there are no real seams to try to match. It allows you to paint with stamps and through stencils and use images that you have created in photoshop or even photos with the projection paint tool. You can create maps for ambient occlusion otherwise called a dirt map and normal map to plug in to the bump node of a shader.

At first I could not get how to use it either alone or in conjunction with Photoshop and Maya. Eric was a great help with this and it is not too hard after all. It is now easy for me to transport images, maps and geometry between the 3 programmes.  Now I am quite proficient with it.

The other half of texturing was Photshop with Lilly. Photoshops speciality is painting and creating images. This was an enjoyable class and I learnt a lot of new things like how to use a tablet and pen, paint in layers and paint images of what we were looking at. Coming from an artistic background of drawing, oil and water colour painting, my pictures looked like paintings rather than realistic photos. We learnt how to use adjustment layers and things like transparency, multiplying layers, colour burn and overlay. I found this very useful especially in how to use layers in mudbox and in making swatches for the fruit bowl.

We also learnt how to use a photo and make a brush from parts of it to paint an image of a surface, say a tree bark or rust, which I used to make brushes and textures for the fruitbowl assignment.

Rendering was a whole new subject. We learnt all about Mental Ray and things like anti-aliasing, final gather, caustics, mental ray shaders, sub surface scatter, motion, blur, depth of field, ambient occlusion, physical sun and sky,  mental ray shadows, render passes, colour balance etc. 

Mental Ray is a much better renderer than the Maya renderer. It can create photo realistic renders.

Anti-aliasing is critical in rendering. Without it you can get jagged or stair-stepped artifacts along diagonal edges or where there are a lot of small objects or lines together. (Birn, 2006, p. 259)

Global Illumination is wonderful, the programme computes the bounces of light between surfaces and the colour bleed that happens, it replaces fill lights and their shadows (Birn, 2006, p. 74)

We had to render 3 objects to look the same as 3 real world objects and I really like how my gold shiny christmas bauble looked but I forgot to adjust the samples on the glossiness for my pink plastic elephant watering can and the shine was too grainy.

Finally at the end of this semester we were given a few weeks to texture and render a scene in Maya using all we have learnt in Rendering and Texturing to produce realistic looking fruit, light and a glass bottle of water in 2 scenes with 2 lighting scenarios. It is such a huge assignment with many blog posts required as well as just doing the thing itself, I hope I can do it all in time by 5pm tomorrow!

I had lots of trouble at the start trying to figure out how to use Mudbox and the pipelines between the programmes. I had some difficulty after making what I thought was a good sculpted texture Mudbox to show up in a render but it was the size of map I was exporting 32 bit and 16 bit floating had too much information and it didn’t work until I made a 16 bit or 8 bit integer map. It takes me a very long time to get the renders I am happy with starting from making brushes and textures and maps to placing lights and cameras and working out the best render settings and waiting for each test render to show results before twiddling things and trying again.

Overall I have learnt heaps in these subjects. It seemed too much to learn but it is possible after all. UVLayout, Mudbox, Photoshop and Mental Ray are now tools I can use in the pursuit of excellence in texturing and rendering.


Birn, J., 2006. Digital Lighting and Rendering. second ed. Berkeley(California): New Riders.

Derakshani, D., 2011. Introducing Autodesk Maya 2012. 2012 ed. Inianapolis(Indiana): Wiley Publishing.

Honn, E. K. w. P. a., 2010. Mastering Autodesk Maya2011. 2011 ed. Indianapolis(Indiana): Wiley Publishing.

Fruit bowl progress report 3

I am on the final run. I have assigned textures to everything.

I have been trying out lights, eg whether to use physical sun and sky or normal lights.

Weakness– I had put  in lights at the start but light linking the caustics and grapes lights may be what stuffed up my renders and shadow from the window. Nothing worked so with Chris’s help I deleted all the geometry and imported an earlier one now the window has a shadow with a directional light.

Then I discovered that every spot light I made for outside the window had the same trouble.

Strength- So I made a directional light and changed the light angle to blur it up a bit.

Strength- I am putting in ambient occlusion on the shader nodes to have more of so that it all looks more real with that and I like the way that looks.

Weakness- I am fiddling with the grapes subsurface scatter node’s specular layer and am discovering that I can make the shine look more like that on real grapes, more diffuse. But I am still not happy with the look, I want it to be more cloudy on the surface.


I still want the lighting to look realistic. I am getting either too bright or too dark with the phyiscal sun and sky so that may have to go.

I want good caustics too.

Fruit bowl progress report 2


I am having heaps of trouble trying to work with Mudbox and the pipelines between it and Maya and Photoshop. However I made a tiling stencil in Mudbox  and made a good skin for an orange. I managed to make maps for ambient occlusion and displacement. I plugged them in to the mia shader in Maya in diffuse weight and bump and the look is way over the top. Every step of the way takes me so long because I am learning as I go and trying everything.

Here is what I have at the moment. It needs shallower pores and I should do the map again with no blurriness. That came from sculpting through the stencil on too low a level in Mudbox and doing it on the side at an angle where it is blurry. I realised later that I had forgotten to make the grid larger by 1,000 in maya and to make a huge copy to export because the scale is bigger in mudbox.


I redid the orange and maps in Mudbox got better maps and plugged them in to  colour weight and bump and fiddled with reflection and gloss; and painted a colour in Photoshop, which I plugged into colour in the mia shader. I am much happier with the result. However it needs better pores and more ambient occlusion.



The lights for the grapes are casting light where I don’t want it so I am light linking a back light and a front light to them and seeing if that looks better.

Not too sure what to do wtih a displacement map or AO map, and not getting good results in my renders.

Today, Tuesday, we learnt how and where to plug in a displacement map into a mia material x shader so now the orange can look better than at first when it went into the bump part. You drag it into the shader node instead, there is a dedicated part called displacement map.

Today, Wednesday, Eric came and helped me with all the problems I am having with Mudbox. I learnt we only need a normal map and an AO, or dirt, map for Maya for this assignment, the other maps displacement and vector displacement are for modelling. Also how to sculpt the surface for blemishes and creases and that these will be saved in the normals map and plugged in to the bump node in Maya. He also taught me how to find and use the painting that I do in Mudbox and how to paint a grey scale image over blemishes for the reflection part of a maya mia shader so that these parts will be less shiny, and to paint in dirt in crevices for the dirt map. Also I learnt that we make a stencil in Photoshop like Lilly taught us and how to bring it in to mudbox and that we can use that as a stencil or stamp.

Friday- time to practice what I learnt… it takes ages to get the results I want. I am redoing the orange and bananas in Mudbox trying to get them better looking. I started in Photoshop and made new stencils. I also tried the mia skin shader on the orange to see if I can give it a more realistic look with the depths. That didn’t work well. So it is back to the mia_material _x.

Made a better stencil for the orange in Photoshop, imported a huge orange to Mudbox and subdivided it much more and made bigger deeper pores with the new stencil and creases, hoping the new normals and ambient occlusion map work much better. At this rate I am not sure I will finish it.


Spent days and days of stuggling with the orange and frustratingly finding that absolutely nothing worked.

The problem was figured out with Eric. 32 and 16 bit floating settings when extracting the normal map in Mudbox meant there was too big a range for the renderer to find the information and the result was always too different, flatter than what I had sculpted in Mudbox. We experimented with these settings and found that 16 bit integer was much better but hardly any better than 8 bit integer so finally with this setting I have an orange.

Strength- it look  like an orange now



More troubles


Whenever I have painted a specular layer in Mudbox for a reflection map by painting black where I didn’t want reflections the result, when I plugged it into reflection in Maya, was that the whole thing became as shiny as a mirror.

So I looked at the reflection value that I had chosen in Maya with out the plug in and painted that value of grey on the layer in Mudbox where I did want some reflection, say .03, the result was always the same a shiny mirror surface, even where I painted a value of 0.

It is very frustrating so I left it out and just used the low reflection value for the whole thing. They looked pretty good in a scene on their own but back in the original scene it’s a disaster.


Below is an example of the very shiny apples which have been causing me grief.

The avacado looking pear and the speckles which will hopefully be fixed later with rendering settings, like samples.

shiny apples


After adjusting the reflection I am happy with the apples.

my red apple

my red apple

my green apple

my green apple

Weakness- Grape Stalk

I didn’t like how it was angular and tried a round corners mia thingy but it didn’t look right.

Strength Then I plugged a displacement node in to the shader group and immediately it looked more normal in the render.

As it stands now


This is based on one of the photos we were given with outside light coming from the right, here through a window, as in late afternoon or early morning. I may colour the light, trying pink or yellow, to make it more realistic for morning or afternoon.

Strength- This screen grab of a render has no GI or FG and low sample rates to quicken the render time, but I am happy with the way the fruit and the wooden basket look now.

Weakness-  Grapes still not good enough- The lighting behind the grapes is a bit wrong with more light on the left away from the light source than the right. the lights may be too close and causing uneven patches of light.

Desire- A desire that I have is to have the window cast a shadow but I can’t make it do it yet.

Strengths- the fruit look good now the apples and bananas look real to me.

Desires- The pears and grapes could look better. I want my grapes to look more real with maybe some cloudiness on the surface. I have tried green pears and brown pears.

I have to finish getting good lighting and setting up the scenes

I have to do good caustics yet. I want concentrated refractions of light coming from the bottle.

I want good realistic shadows.

Fruit bowl progress report 1

We have been given a model of fruit in a bowl and a bottle, to texture and render as life-like as possible. I am looking at references like the photos and real fruit and bottles as I do anything.

I started by placing lights to light the scene and some cameras for the 2 views but as I apply shaders I am experimenting with lights and camera angles for the best results. I attached a measuring tool to the lens of a camera, using the node editor I plugged the distance of the measurer into the depth of field of the camera so the focus length is always the same as the far end of the measurer tool and I place that where I want the camera to focus. This is good for close focus with things behind and in front out of focus.


I applied mia_round_corners shader to the grapes stalk to make it rounded in the render view rather than angular as the model is. I also put it on the wood so that the corners on the wood would not be so unrealistically sharp.

The grapes have sub surface scatter so I applied a misss_fast_simple_maya shader to the whole lot of them, 191 grapes. The grapes are not exactly the same colour so I applied a randomised diffuse with a mel script written by a teacher. Now they are all differing according the the different green colours I put in the ramp. Varying the values on the shader with light behind and in front, it is quite difficult to get them looking like grapes and not olives or lights. Also they look quite granular so I think I have to improve anti-aliasing and samples.


I have started the bottle of water. I made a light for it with intensity at 0 and made it emit photons only, caustics after turning on caustics in render settings, indirect lighting tab. I made the light face the bottle and enclose it in the cone angle. I am in the process of fiddling with the photon settings of the light to get good refractions or caustics. I increased ray tracing samples for reflections and refractions on the quality tab and same for the photon tracing on the indirect lighting tab. I reversed the normals of the water  sides and top inside the bottle and applied mia_material_x shaders to them. I am very happy with how real it looks but I think I need to do more to get caustics showing on the bench and also the bottom of the bottle needs more attention I think.


Weaknesses- The grapes don’t look real they look like lights, I need to spend more time on them to stop them looking like plastic lights. They are granular too.  The stalk doesn’t look right with the rounded shader on it and I will have to discover a better way to make it not be angular. The caustics are not right yet. I want to see the bottom of the bottle too.

Strengths- I like how the grapes have real differing green shades and there is subsurface scatter going on.  The depth of field is working nicely. The bottle of water is transparent and looks like what it is meant to be.

Desires- I want the grapes to have the right amount of subsurface scatter so that they look like grapes not plastic or olives. I want the caustics to shine sharply on the surfaces around and to see the bottom of the bottle too.

rendering- adding an object into a real life scene

First  we had to pick an image of a temple and set up the camera in the right angle to view it as if from the original camera, and model a set the same as in the photo.

We had to research how to use and integrate mip matte shadow and mip camera map shaders and we had to pick a picture of a buddha make a buddha model’s surface look like the buddha in the picture and put it in the scene.

Inside_a_Buddhist_Temple,_Thailandoriginal photo

buddhaMayaOn the left are the models of the set and buddha, on the right is the view from the render camera

I worked out how to use them all except for how to make the reflection of the buddha only appear on the shiny floor and nowhere else. I tried a black and white image where only the floor was white and also the opposite where it was the only black, plugged them into the refl colour of the matte shadow node and when it didn’t work I tried plugging it into anything I could in the reflections part of this shader, but it was either refelective in the whole scene or not but not just the part I wanted- requires more investigation.

I tried to make the buddha look like the gold ones in the temple and this was as close as I could get. I am happy that it looks real and like it is really there. the reflections of the carpet in the buddha and his shadow on the carpet are from these 2 shaders and the lighting on him matches the lighting in the temple.

I made the render image the same dimensions as the original photo- 2079 x 1446 pixels.