We all know what water can do to render times ! My dilemma is that to try and get render times that don't go off into infinity, I seem to be making more and compromises to the overal quality of the picture. Can any body suggest tips that can speed up the render of the water without losing out overal. Using Vue 5 Pro Studio BTW.

www.CambrianMoons.com

No tips, really, water takes a long time to render. Maybe reduce bump, but do keep some, unless you want to render a very still lake, you can also reduce the reflective angle to get less reflections. Check that you are not using a material that has blurry reflections and/or transparency.

Lower trace reflections and transparency to 1.

Won't work, CobraEye, apparently this setting doesn't apply to water. You can set it to 1 or 12, it will be just the same. This parameter only works when the reflectivity channel is active, not this "fresnel like" reflectivity that is activated in the transparency channel. As for transparency, it is always computed the same, I don't know why this parameter is active for transparency.
And it's Infinite only, btw.

Basically theres just a few things that really eat up loads of rendering time:

• Reflections (Water, glass, metals, liquids, etc) . Depending on the scene it might sometimes be possible to reduce the number of reflective materials used. Transparency also effects render times when the "turn reflective with angle" is used.

• Depth of Field: A true killer for rendering time. Not really much you can do about it, besides dropping the DOF and doing it in postwork

• Ecosystems: Ecosystems with thousands of plants can eat up loads of rendering time. its much less compared to working with individual plants, but large ecosystems can cost you much rendering time. Try making it smaller by covering parts with large plants /objects and deleting the covered part of the ecosystem. Also try lowering plant resolution for polgon count and texture resolution, especially for plants that are far away. Just scale the plants larger, re-populate and you will also have less plants to calculate.

• Atmosphere A spectral/Radiosity  atmosphere will render much longer then a Standard/Standard atmosphere.  I have made some standard atmospheres that  look quite good on many scenes and greatly reduce rendering times.

• Complexicity: If you have millions of polygons used for imported models, then try thinking about reducing their polygon resolution or just using fewer of these.

• Lights: Dont use scenes with like 100 point lights, these can also be a killer.

• Shadows: soft shadows with quality boost take up quite a bit of rendering time. You may want to try adjusting the quality bias if you dont have shadows in the foreground of the scene

• Rendering settings: Most errors are done here. Some users render their scenes in Superior/Ultra mode and boost up their rendering times. While this definitely looks a bit better just think of what you get. often you buy a handfull of Anti-Aliasing for hours or days of render time. Use a custom set-up and reduce all AA  related settings. You can often get much better effects within seconds when using external programs, i use GIMP and neat image, these can in most cases do in seconds what takes Vue ages. Yes that may be a bit cheating, but if the final result is the same or even better i think this might be worth a try.

theres many more little things you can tweak. If vue keeps your HDD busy during render, then physical memory is the bottle neck, try to refrain from rendering such scenes as they take like 10 times longer when you lack the ram.

Vue content creator
www.renderarmy.com

You are right. It doesn't help render time, but does change the color of the water.

Really, CobraEye?  I tried to up the reflection passes once, but couldn't see any change in the water quality. Will try again. Thanks.

I noticed the change when the setting is switched from 1 to 5.  It is quite a surprise that it does not change render time.  Thanks for the excellent explanation.

Very visible indeed. My user settings always use 5 levels of tracing. Have you seen any improvement if you go over 5?

Some useful suggestions, many thanks. I'm wondering perhaps I should render the scene with water at a lower quality setting, and then render the scene again without the water at a higher quality setting and use a mask to combine the two. My render is still running and the skin tones on the figure are noticeably poorer with the lowered quality settings. :-(

www.CambrianMoons.com

I think it is a good idea.  I've often thought about doing it myself, but I usually just go for the long render.

Bruno, I see no improvement over 5.

Ok, CobraEye, this is why I neversaw any improvements with this feature, because I always start at 5. Good to know there is no need going over 5.

godrays & water are the kiss of death for render time. i've given up on seascapes & godrays.

"godrays & water are the kiss of death for render time. i've given up on seascapes & godrays."
kore21 - I found out the hard way on this as well!

You might consider turning OFF transparency for the water...if you don't need it. It will substantially decrease the render time.

 

what does turning off the transparency do to the look of the water? also, would objects/terrain under the surface no longer be seen?

Turning off transparency for water would make water look like a metal material. Objects underwater would no longer be seen.It's a good trick for distant water.

hmm, could be interesting for some things. i'll take a look sometime.

i just have the latest patch on, seems they fixed the memory leak & my rendering is a lot faster. as a matter of fact it's about 1/3 of what it was, so far experimenting w/ "optimize last render pass." godrays & water may be saved from oblivion....

Optimize last render pass  speeds up the render times, but is less acurate, since it evaluates the lat render pass from the previous passes, without raytracing. It can become really ugly with advanced lighting models. You can't network render with this option on, btw.

i've been experimenting with "optimize last render pass" since many other ppl have recommended it. mostly with relatively uncomplicated things. a few of them have come out with smudgier areas, or a little flat. render time was 1-3 hours using a spectral atmosphere, for what was previously 7 (not counting godrays). so i will probably be using full quality most of the time. which means where do i put the quality boosts, these increase the render time. for example, i'm often running 2+ on the sky, fog & haze panel. lowering this unfortunately changes the color/quality of the sky too much for my liking. seems it's easiest to decide first what you want the quality to be, THEN design the atmosphere for best results. some ppl have said you must have 4+ for rendering godrays, that's the only one i've ever tried. most of the time i've aborted the render, since it wasn't practical & kept my computer tied up too long. if they've fixed the memory leak it's now worth a try to render godrays.
 
notice they also fixed the anti-aliasing, where it got stuck on "soft" & water turned to metallic sludge. crisp seems to work now.

The atmo quality boost should only be used if you see grain in the clouds. Because that's all this parameter does: increase the cloud samples to avoid grain. It doesn't change the sky colour. Of course with godrays, most of the time you need a +4, because your clouds have to be very dense and thick, with a lot of shadows to compute, and the grain comes where the shadows are.

thanks. i like playing with the hazes, i find if i turn it down too much it looks a little flat or something. 

one thing i noticed with godrays, the graininess seems to be extended somewhat beyond the cloud itself, basically increasing graininess in the sky color. thought this was a bit of a nuisance to get rid of. found lowering the cloud opacity helps here somewhat.  

Lowering the cloud opacity will reduce grain,but maybe the godrays will be less visible too. It's a trial and error thing. Sahme it takes so long to see the results.