VRay render is always hazy

[titusc]

Hi I'm learning VRay and Sketchup here and for some reasons my rendered outputs are always appearing to be hazy, and a cabinet I'm trying to render always appear to be quite bland. No matter what resolution and quality I set they still appear that way.

Here is a close up render. We can't see much if any detail.

Here is a render of the whole cabinet. Again it just doesn't look real.

Here is the zip file containing both the Sketchup SKB and V-Ray Options VISOPT files.
SKB and VISOPT Files

The overall render no matter what I do just doesn't appear photo realistic at all. There must be something I'm not doing right. I'm not sure if it's the lights, the materials, or the settings. In terms of quality I have already set the highest and render time actually takes quite long. I haven't timed it but I'm sure it's over 45 min. For the large image, I actually went to bed and wake up the next day to see its output.

Can someone let me know what I need to do to improve on the quality and make it photo realistic?

Thanks.

[Carto]

Hello titusc, I'm by no means the expert on these forums but right away I would say your lighting is a problem. It appears as your scene is lit with only the sky. Keep in mind rendering is just like photography, without good lighting you will not have a good image. Search online for studio lighting setup and IBL lighting (HDRI). In addition your materials, surroundings and camera settings will also have a significant impact. Checkout the link below from ChaosGroupTV, it contains a great assortment of videos to walk you through the basics. Cheers.

[Stinkie]

Bevel your geometry, apply texture maps (diffuse, bump, and if need be, spec maps), set up your lighting in a realistic manner, and if your materials are reflective, make sure there's stuff in your model to be reflected (be it actual geometry or an image mapped to a plane, or an environment map).

[titusc]

@carto said:

Hello titusc, I'm by no means the expert on these forums but right away I would say your lighting is a problem. It appears as your scene is lit with only the sky. Keep in mind rendering is just like photography, without good lighting you will not have a good image. Search online for studio lighting setup and IBL lighting (HDRI). In addition your materials, surroundings and camera settings will also have a significant impact. Checkout the link below from ChaosGroupTV, it contains a great assortment of videos to walk you through the basics. Cheers.

Hi Carto thanks for the pointers. I'll check out the link later on.

1. I actually looked at the IBL Lighting technique but I have understood it as a way of providing background scene based on real image. This actually is beneficial to make the scene looks more real with real clouds in the sky or grass on the ground as an example. However I thought that's where the benefits stop, and the actual light coming from IBL shall be the same as if I'm not using IBL. I guess you are suggesting that this is not the case? But how can any one do photo realistic render before IBL is available?
2. For studio lighting are you referring to IES?
3. In my model I actually am modelling cove lighting all around by using the VRay's Panel Light. I thought this would give quite a bit of light and should be sufficient to lit the scene. Are we saying despite this is the case just because the way it renders it still needs IBL in addition to having properly lit internal lighting sources?

@unknownuser said:

Bevel your geometry, apply texture maps (diffuse, bump, and if need be, spec maps), set up your lighting in a realistic manner, and if your materials are reflective, make sure there's stuff in your model to be reflected (be it actual geometry or an image mapped to a plane).

Stinkie also thanks for the comment but ...

1. Can you elaborate what you meant by "bevel your geometry"?
2. For the materials I used VRay material, clicked on the "M" button on the Diffuse layer, and selected the texture option. That's how I created the marble floor and wood pattern for the cabinet. Are you saying this is not enough and we need to use a photo to apply texture instead?
3. What are "spec maps"?
4. "set up your lighting in a realistic manner"
   I can totally use some pointers on exactly what I need to do here.
5. "make sure there's stuff in your model to be reflected"
   Um ... I actually wanted the cabinet, walls, ceiling all using a matt paint color. The only place where there can be reflection is the marble floor. Are we saying for rendering in order to make things photo realistic, even matt surfaces need to use some gloss by adding a reflection layer?

Thanks!

[Carto]

Hello titusc,

In regards to the link, better sooner than later because theses videos will answer many of your questions.

1. Depending on what you are rendering (scene or product) you would utilize the appropriate type of lighting. For example if you are trying to render just the entertainment center, you may setup a studio type scene just as a photographer would with multiple light sources. In addition by utilizing HDRI you could add some realistic reflections. See the attached example (one with HDRI lighting the other with a basic dome light). I hope this illustrates the importance of proper lighting. There is no single magic solution to rendering, all of the elements working together is what creates a realistic render.

2. No. The type of scene setup for rendering a product.

3. You will always need multiple light sources, just as in real life (see example with HDRI and two rectangle lights).

As I mentioned before I'm not the forum expert and maybe somebody else will chime in with a better explanation. Cheers.

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[cuttingedge]

If photo realism is what you're looking for in a render.There are 4 aspects to it:

1.Model- go as detailed as you can .. round the corners and edges, make sure there are gaps between objects so no clashing between objects.

2.Lighting. Make sure light source is balance. Try not to do much dummy light. let every light come from a pre-defined source, say window, lamp, etc. Unless you're doing a studio render, decide which time of the day you like to project in your scene.

3. Materials- In reality, all materials has some degree of reflection. leaving one without reflection will make it dull.- Be conscious also of your mapping and texture scale.

4. Vray settings- try to go higher settings (not the default) add Ambient occlusion and use the in-built color correction tools in the vray buffer.

It will greatly enhance your image if you use photoshop. Even the best of the best in visualization use these tools.

Invest time in reading the manual and do tests yourself. you'll be amazed at what you can discover.

The easier way though is to download some render-ready models. and see the settings. You can even grab the materials that you like and include in your library.

these are the basics but there are hundreds of parameters you can experiment on.