Realistic Rendering...

[Guest svangeldern]

Rendering Geniuses (I mean it in a good way),

 

Attached are two renderings. One was done in Ironcad and took 8h 33m 28s to complete. The other was done in Deep Exploration from an Ironcad "sat" export. DE took 5 minutes to complete. Both were generated on the same hardware.

 

Why does one take 8 hours and the other 5 min? Which "realistic" rendering would you use in a presentation?

 

Cheers,

 

Steve

 

[Bryan Cargill]

My guess for the long rendering time is that you used full GI?

 

If you are concerned with render times-- then I suggest finding alternatives to GI. Only use GI if you really want to include the light emitting from the background-- or if you want a fast setup- but slow render times.

 

If you do need GI, then try turning on the cache. It will speed up results dramatically-- and will sometimes yield a better image as some of the noise is averaged out.

 

Also, don't use FULL GI unless you want to include the effects of radiosity and caustics. Even if you do want those effects they can be accomplished very quickly by different means. Try using direct caustics and radiosity-- options on spotlights. This approach can be much faster because it is a local effect-- not a global one.

 

Also, be careful with unnecessarily high super-sampling settings- it can significantly slow down your rendering. Super sampling is actually doing more rendering-- in between the pixels. Don't use it when simple Antialiasing in post-pro will suffice.

 

Make sure facet counts are not unnecessarily high-- and that there are not extraneous parts in your scene by eliminating hidden and contained/obscured parts where possible. (Apparently not an issue for this file in particular).

 

As far as quality is concerned- your lighting setup and camera angle don't seem the same between the two images. I'm confident IC can produce an image of similar quality to your example.

 

Of course there is always room for improvement! We appreciate your comments.

[Cary OConnor]

First question is what settings are you using to make it take 8 hours? Most likely you have the perspective turned off (Turn it on – Our rendering is not meant for non-perspective renderings especially if you added a 3D Environment).

 

There really is nothing in that file that should require you to take 8 hours. (unless you are rendering a very large size for print production). I created a similar one and it is about a min or two depending on the size.

 

The image in this case could be done in a Photoshop application in a fraction of the time in a rendering system and at a larger resolution for print since it really is not that complicated and doesn’t really show much in the terms of realism.

 

The realistic rendering in IC should take longer when you start adding specific lights, reflections from environments, glass, and more complex scenes.

 

If you attach the IC file, we can take a look to see why it is taking so long.

 

Cary

 

[Guest svangeldern]

Guys,

 

I'm sure the long rendering time is because I don't know what I'm doing....(don't tell my clients).

 

Bryan - GI set to none.... Super Sampling was set to high. Changing Super Sampling to low only yielded 5% render at 5 min. If by facet counts you mean surface smothness I have it set at 50.

You are correct about the lighting. I created a spotlight in IC and used the "sun light" setting in DE.

 

Cary - Perspective on....render size about 1024x768 (I want to use the image for a GUI I am creating in VB for a machine we are building).

 

I have rendered much more complex scenes in resonable elapsed times. Obviously I have something wrong. The question is..what? Also, how can I avoid this issue in the future...

 

I've attached the file in question for you reference.

 

Thanks,

Steve

ControlPanelBackground.ics

[cborer]

Hi Steve

The finisch of the grinded Stainless steel looks great !

Can you offer that as a jpg?

Thanks

Carlo

[Cary OConnor]

Well there are a couple of possible reasons it is slow.

 

1. Emission - This is slooow (probably the main reason it is 8 min). Do not use it unless you really need to have a surface emit light. In this case the part is reflective so it will reflect the light but I don't see why you need the emission.

 

2. I don't have all the images so I can't say if they are causing anything slow in the file.

 

3. Turn on the raytraced light shadows (it is better in the realistic engine). The soft shadows are better but are slower.

 

4. When I opened the file the perspective is off. Turn it on.

 

If I make these changes, the file renders in about a 1 min.

 

Cary

[Guest svangeldern]

Cary,

 

Thanks! It was the Emission setting....

 

Carlo,

 

jpgs attached...

 

Steve

 

Carlo, I added the Oxidized Plate which I actually think is the one that

interested you most..

 

 

Edited March 21, 2008 by svangeldern

[Bryan Cargill]

Sorry, I didn't even suspect there was emission in that scene.

 

Emission will simulate light emitting directly from the surface. It does so by effectively placing many tiny area lights across the surface-- facing outwards. Depending on the settings, this can be a real bottleneck.