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Per-Anders
09-13-2006, 07:05 AM
Top four things that people do wrong with the C4D render engine:

1) Poor AA - People never bother to try out the other AA algorithms, try using Sinc if you want sharp or Cone for a simpler AA, learn to use the best AA settings, the tolerance values and so on.

Experiment with the sharpen, median and soften post effects too, for a nice effect just use a sharpen effect set to between 5% and 20%.

2) Bad lighting - If you want realism then don't use soft/shadow-map shadows, soft shadows are a big culprit in the painterly look that many perceive in C4D renders, instead use the ray-traced shadow setting either hard or area, these may take longer to render, but the results when used right are worth it. Again check the shadow settings and learn to tone them down, for scenes with multiple lights or GI they're generally set to far too high settings.

Reduce the light contrast, -50% is good, this gets rid of the harsh terminator on objects and gives a good clean result.

Don't be afraid of using the light falloffs, inverse square is a natural falloff. Get used to using area lights and spotlights.

Avoid ambient lights as much as possible they will wash out an image, it doesn't look like GI (apart from GI in certain Arch Vis. renders that's so washed out that really they could have saved the time and just used an ambient light).

Use color in your lights, natural light is never ever pure white, it's always slightly yellow, slightly blue, slightly this or that, it's also frequently brighter than 100% in the illumination tab, use the lights brightness setting.

Experiment with the color correction post effect to modify your Gamma, try a range between 1.6 and 2.2 for a more natural looking effect.

Learn to place your lights well, use the Look through selected option to help in the editor, always remain true to your scene, if light should come from a source then add it, if it shouldn't then don't have it there.

3) Poor materials -
For stills don't be afraid to use different sample settings for your bitmaps in your materials, MIP is good for animation as it helps get rid of the creeping effect, but for a still you will most of the time want something much sharper, for example Circle.

Use the right illumination model. 99% of the time you're not making something plastic, yet 99% of the time people use Phong. Phong is not a realistic illumination model, it's a simple basic one that's really only good for plastic effects. Try using the other illumination models where necessary and you'll find the materials will start to be more believable.

Understand what's going on. Learn how the materials are made up and what the components are meant to do. Specular is a simulated reflection of the light source, therefore if you're using a texture in the reflection channel it should be shared in the Specular color channel too. Diffuse is a diffused or to put it another way blurred reflection of the incoming light, i.e. it's possible to physically simulate this using blurry reflections (not that I'd recommend this, but it pays to play). Experiment and learn how each channel is working, it will pay off.

Don't overuse speculars, fat wide speculars look both cartoony and plasticky. On the other hand do learn how to use them and experiment with multi-layering them together using the lumas shader in your luminance channel (and the layer shader).

Every material has some fresnel reflection, you don't always have to add this in, but it's there, often diffuse and very faint, e.g. on skin, but it is there. Consider adding it in when going for accuracy (and be prepared to pay the price in render times).

Reflection and color are balanced, the harder a surface the less diffuse it will have, a mirror has virtually no diffuse/color element (unless it's very dusty), it's a hard shiny surface, a the less shiny a surface the more diffuse color it will have.

4) Lack of post processing - Virtually no really good renders are the result of anything coming direct out of the render engine. If you want it to look good then start to play around with the image in Photoshop or After Effects, all the best images you see have fairly heavy post work from color correction to added grain and photographic style effects e.g. lens blurs, glows, artifacts, grains. Doing this extra step will drastically improve the overall result.

JoelOtron
09-13-2006, 02:35 PM
Excellent pointers. Hope this thread grows.
To add to your bad lighting section where you speak of using colored lights:

I always use colored key lights, making sure that I also choose a complementary color for my fill, and continue this trend with each light I add to my scene, pairing a contrasting colored light with each added light. For instance, if your key is yellow or orangeish--I go with a soft blue, or slightly purplish fill light.

Adding several subtly colored lights to a scene can really help add depth to your image--and sometimes may even help your image begin to approach an almost GI look (treaded carefully on that comment.) :)

projectk
09-24-2006, 12:22 PM
Hey Per,

I read through this article, but i am still unsure. (http://www.the123d.com/tutorial/general4/reflections2-1.shtml)

So....What would you use blinn or oren for? I was always using phong...From what i think i picked up, the latter good for metal?

PS. Nice checklist. :D

Per-Anders
09-24-2006, 10:27 PM
Bother Oern Nayar and Blinn have a more physically accurate specular model with a more precise falloff based on the ammount of incoming energy, as I pointed out in teh article it's very simple, phong creates a plastic look, therefore you only use phong for plastics and some simplistic metals, therefore you use blinn and oren-nayar for everything else. Oren nayar differs from blinn in that it doesn't use the standard lambertian diffuse illumination model, it is good for porous surfaces, things that are either dusty or have many thousands of microdents or facets - plaster, bricks, pottery, ceramics and so on. They're both versatile shaders and can be used succsefully for many things, not just the basics, from skin to cloth.

projectk
09-28-2006, 09:40 PM
Awesome, thanks Per. :D

Per-Anders
10-04-2006, 06:33 PM
In addition to what's already been mentioned another thing recently came up in a thread elsewhere and that is "How can I improve the look of the C4D Bump?". Well the answer is actually surprisingly simple. In many procedural shaders you will find a setting mysteriously called "Delta", it's a diminutive setting easily overlooked, but this is most frequently the key to getting crisp and good looking bumpmaps.

How to use "Delta", and how it works.

To improve the quality or sharpness of your bumpmap simply lower the Delta value, very low values will result in the apparent height of the bump map lessening so you will have to compensate by increasing the bump map strength (don't forget that as with many sliders in C4D the bump strength value can be set higher or lower than the actual extents of the slider), but they will also result in the bump looking crisper and better defined!

Don't set it too small though because the smaller the Delta the more likely you are to get "Flicker" and "Strobing" surfaces without setting up super high AA values.

So what is it going? Delta ias actually controlling the distance between the samples used to create the bump maps surface normal (the direciton teh surface apparently faces), the closer togehter they are the sharper the result the further apart the softer and less defined. To get technical typically three samples of shader brightness are used from three points close to each other and the surface normal is taken by the cross product of these values multiplied by the strength setting. If they're too far apart then what happens is that finer detail will be missed in the gap between the actual samples.

To go along with this, when using Bitmap's as shaders you may frequently want to lower the MIP settings into negative in the bump channel, or for stills even turn off the MIP altogether and choose something else such as Circle sampling in order to get the crispest possible result.

loureed
10-12-2006, 12:37 PM
Thanks to this post I finally came up with some good settings for exterior set up.
Before I was strugling with Maxwell and FR but I always bump into problems.
Now I want to say how AR is still the best choice for me and with little exploration you can get really nice results.
This is one of my test scenes

http://www.c4dportal.com/forum/attachment.php?attachmentid=1184&d=1160740374

Thank you guys :)

Per-Anders
12-31-2006, 11:00 PM
As an addition to this here's the steps involved in order to keep Cinema set up with reasonably optimal settings every time:

To set up your render settings and scene:

1) File->New...
2) Render->Render Settings
a. General->Name (give any name you want for this preset).
b. Save->Depth set to 32 Bit/Channel
c. Antialiasing->Filter set to Sinc
d. Effects->Post Effect->Color Correction, set Gamma to 1.8/2.2
e. Effects->Post Effect->Sharpen Filter, set Strength to 10%
f. Options->Ray Depth, reduce to 6, Shadow Depth reduce to 6 (speed increase).
g. Save Menu (in render settings window, not Save Tab), Save->Save Render Preset
3) File->Save As... save in Cinema4D application directory as "new.c4d"

To set up your materials and lights:

1) Create a new material (Materials Manager File->New Material), then in the attributes manager...
a. Illumination->Model set to Blinn
b. Click on Color Tab again
c. Attributes Manager Menu : Edit->Set As Default, click Yes to confirm
2) Create a new light (Objects->Scene->Light)
a. Details->Contrast set to -50%
b. Details->Falloff set to Inverse Square (optional)
c. General->Shadow set to Shadow Maps (soft)
d. Shadow->Absolute Bias, uncheck
e. General->Shadow set to Area
f. Shadow->Accuracy set to 50% (speed up!)
g. Shadow->Maximum samples set to 64 (speed up!)
h. General->Shadow set to off
i. Attributes Manager Menu : Edit->Set As Default, click yes to confirm

And that's it. Now every time you create a new material it will be using Blinn as default, every time you create a new light it will have inverse square falloff and a better contrast, and every time you create a new scene it will have the sharper and unclamped AA, gamma correction and sharpen enabled by default, and hopefully this should help you improve the overall quality of the renderings you create.

Similarly to this you may wish to reduce the "delta" setting in several of Cinemas shaders by default and again use a "Set as Default" to store the sharpened up shaders so that next time you use them in your bump channel you will end up with suitably crisp bump maps.

Happy rendering.

Rich-Art
01-02-2007, 08:59 AM
Hi Per,

I have a question about the Contrast in the light tab.
Why is it that you recommend the -50%?

Peace,
Rich_Art. :thumbsup:

Per-Anders
01-02-2007, 09:05 AM
It smoothes out the terminator of the light and light overlaps on surfaces.

Try this simple test, make a sphere and two lights, shift one light out on the x axis a few hundered units, then the other on the z axis a few hundered units, then place your camera between them and render. You should notice a strong line and brightening where the lights overlap which doesn't look too nice. Now select both lights and set the contrast down to -50% and render again, you should now get a much smoother result that's far more pleasing to the eye with a less visible terminator of the lights on the surface.

Rich-Art
01-02-2007, 09:10 AM
Thanks Per,

I did the test and indeed it look nicer with the -50% option.
Never to old to learn....:thumbsup:


Peace,
Rich_Art. :thumbsup:

MrBraun
01-02-2007, 09:30 AM
Tnx for the guide PerAnders! ;) :thumbsup:

okazaky
01-02-2007, 05:20 PM
Thank you for this little guide! It's really interesting.
To get more realistic render results I thought of using blurry reflections instead of the specular channel. Do you think this would make sense?

Per-Anders
01-02-2007, 09:16 PM
Thank you for this little guide! It's really interesting.
To get more realistic render results I thought of using blurry reflections instead of the specular channel. Do you think this would make sense?

Yes, if you read the original post it states as much. Specular is just a simulated reflection of the lightsource, but "real" reflection will give you a far more realistic look provided you're willing to pay the price in terms of rendertimes.

okazaky
01-03-2007, 03:14 PM
Thx, I think I more or less overlooked this part in your first post :)

danb
01-07-2007, 10:38 PM
Very, very helpful. Thank you for posting.

AAAron
01-08-2007, 04:59 PM
Yes, Thumbs up:thumbsup:

MAKLtd
01-09-2007, 08:50 AM
Excellent tips and advice... should be in the C4D manual!

Jazztastic
01-10-2007, 10:26 AM
Thanks to this post I finally came up with some good settings for exterior set up.
Before I was strugling with Maxwell and FR but I always bump into problems.
Now I want to say how AR is still the best choice for me and with little exploration you can get really nice results.
This is one of my test scenes

http://www.c4dportal.com/forum/attachment.php?attachmentid=1184&d=1160740374

Thank you guys :)

I'm glad for you it worked out Loureed , but i am still strugeling with the lights setup. Could you please post your scene with just the lights and render setting so that i can studie them. This would really help me. Thanks in advance.

Taxman9
01-10-2007, 05:55 PM
Interesting article, nice and helpful. I have one question/comment about a point you made, when you said about making lights true to the scene; always remain true to your scene, if light should come from a source then add it, if it shouldn't then don't have it there.
This contradicts what I have read in other places including Jeremey Birns book, that it is okay and quite often necessary to cheat to get the best possible visual result. Which leads me to wonder what you mean by this, and if this is always true or only in specific circumstances?
No offense intended, just trying to learn.

Thanks
Josh

kromekat
01-10-2007, 07:22 PM
Interesting article, nice and helpful. I have one question/comment about a point you made, when you said about making lights true to the scene;
This contradicts what I have read in other places including Jeremey Birns book, that it is okay and quite often necessary to cheat to get the best possible visual result. Which leads me to wonder what you mean by this, and if this is always true or only in specific circumstances?
No offense intended, just trying to learn.

Thanks
Josh

I would have said that that was a fairly subjective tip, as many lights can be used to help with the illusion of reality, or to enhance, and exagerate elements within a scene.

Great tips overall though! :)

Adam

Per-Anders
01-10-2007, 10:18 PM
Interesting article, nice and helpful. I have one question/comment about a point you made, when you said about making lights true to the scene;
This contradicts what I have read in other places including Jeremey Birns book, that it is okay and quite often necessary to cheat to get the best possible visual result. Which leads me to wonder what you mean by this, and if this is always true or only in specific circumstances?
No offense intended, just trying to learn.

Thanks
Josh

No offense taken, but really this is apples and oranges and isn't something you can compare easily. It's not so much subjective as understanding what's meant by that. I'm not talking about only using primary light sources, and Jeremy isn't talking about just slapdashing lights in as you see fit in order to make sure everything is lit up either, Jeremy is talking about technique and I'm talking about composition.

The point I'm making is that your lighting should be true to the environment. It's an important part of the composition, and helps draw the viewer in and makes the environment appear convincing because the lighting tells you what's happening outside of the cameras view.

Many many 3D images are not lit well because light sources come from just arbitrary places, there's no reason for the lightsource and so it looks visually wrong. If you have an object in a room with a window on one side and just walls on all the others you would expect the light coming from the window to be coloured by the ambient sky and sun and perhaps some reflected ground bouncing into the ceiling of your room. You would then expect all other light to be ambient bounce light and coloured by teh rooms walls themselves in combination with that light that's come in (i.e. more intense saturation but less luminance), it's simple. You could convey all of this just via the lighting and reflections on your object without actually seeing any of this, you can also conjvey some other things such as are there any trees out of htat window or is it a grey day, or what time of day is it. What you wouldn't expect is a bright rimlight for instance on your object, or an intense light from any ther direction unless there's a lamp in that direction. However many poeple just light arbitrarily in order to make a silhouette only and they focus purely on their central hero object, when perhaps they should be focussing on the background, on making sense. Your lighting has to reflect this. That's not the same as your light objects have to reflect this.

Your lights can be anywhere, they can be any type of light, however their purpose is to create the effect of light coming from very defnite and precise locations, and from understandable points.

If you have a random light floating in the middle of your scene and you can see it's falloff going out from it then the viewer is going to wonder where the lightsource is, it should be visible, but it's not. That's bad lighting. If you have a light htat apparently eminates from nowhere, from where clearly there shouldn't be light, then that's also bad lighting. If you use flat white lights always with no concern for environmental matters, then that's also going to lead you to bad lighting. If there's an object in the way then it should block off the light, light shoudln't pour through it. This is really common sense stuff. What Jeremy and others are talking about is how to use your lights to achieve this effect, not how to compose your image or create and design a sense of immersion, of reality or solidity and dynamic to your scenes.

Per-Anders
01-10-2007, 10:41 PM
Now for a couple of extra small lighting tips that under certain circumstances will save you a bit of time.

The "Ambient Illumination" mode of C4D's lights. This is a much ignored option, and rightly so 9 times out of 10, the original purpose of ambient illumination was to simulate global illumination before 3D apps had global illumination. Indeed today you can in many situations get away with using ambient illumination instead of GI for the more simplistic forms of Arch Viz (in fact many Arch Viz renders already look like they're only using ambient illumination anyway so there's no point in bothering with GI itself in those cases as ambient illumination will render many thousands of times faster).

So what can we use it for? Well, there's a few things.

Firstly in conjunction with global illumination itself. GI tends to slow down in extremes where there is super bright or super dark areas, adding a very dark ambient illumination light (with no specular on) can allow you to reduce the number of bounces of your GI whilst still getting a good lighting level and speeding up the GI calculation itself on top of that (and helping smooth out the GI result thus allowing you to frequently reduce the samples used too). So it's useful as a GI helper.

Well what about replacing GI? Can it still be used for this? The answer is that in some situations, yes it can. For instance a very popular look still is the clay render and "physical sky", you can emulate this look very much faster than with actual GI by doing the following:
1) Make an ambient gray-blue light, set it to be quite dark.
2) Create a light for your sun, give it a slightly orange/yellow tint, and a hard or area shadow, possibly turn the lights brightness above 100% depending on the light location (time of day).
3) From the render settings turn on "Ambient Occlusion"
4) Render
Your object should now have a nice very smooth and relatively quick "physical sky" look. With careful tweaking of the light colors you should be able to approximate most daylight lighting conditions without having to expend precious CPU cycles on full on GI.

So what else is there that this little feature can do? SSS is what else... ok admittedly it's very choppy and useless in 99% of cases, however here's how to create an ultra simple and ultra fast SSS effect. Create an ambient omni light, turn on soft shadows, and now just play around with the shadow bias in order to control the depth of the poor mans SSS effect (and use the Scene settings to include/exclude objects from this effect).

Finally of course it can still be used for cheating GI itself and for overall color matching.

Hopefully that should give you some ideas for how to use and abuse the ambient light option of your lights for quick and not so dirty effects.

nycL45
01-10-2007, 11:35 PM
Very enjoyable tips/suggestions you are putting down Per. Bravo! and another helping please.

Question: in your post excerpted below, steps 2c, 2e and 2h change the shadow settings with 2h turning the shadows off. Are those shadow settings retained somehow? Or, does 2c & 2d give access to certain settings otherwise grayed out? What is happening there? (This could be a "duh!" moment.)

To set up your materials and lights:
1) Create a new material (Materials Manager File->New Material), then in the attributes manager...
a. Illumination->Model set to Blinn
b. Click on Color Tab again
c. Attributes Manager Menu : Edit->Set As Default, click Yes to confirm
2) Create a new light (Objects->Scene->Light)
[indent] a. Details->Contrast set to -50%
b. Details->Falloff set to Inverse Square (optional)
c. General->Shadow set to Shadow Maps (soft)
d. Shadow->Absolute Bias, uncheck
e. General->Shadow set to Area
f. Shadow->Accuracy set to 50% (speed up!)
g. Shadow->Maximum samples set to 64 (speed up!)
h. General->Shadow set to off
i. Attributes Manager Menu : Edit->Set As Default, click yes to confirm

Per-Anders
01-10-2007, 11:42 PM
Very enjoyable tips/suggestions you are putting down Per. Bravo! and another helping please.

Question: in your post excerpted below, steps 2c, 2e and 2h change the shadow settings with 2h turning the shadows off. Are those shadow settings retained somehow? Or, does 2c & 2d give access to certain settings otherwise grayed out? What is happening there? (This could be a "duh!" moment.)

They are retained for when you want to switch shadows on at whatever time in the future. It just means the setting is there so you don't have to set it up time and time again and can instead just switch on shadows and know you'll have the settings you want. It's worth remembering with area lights and area shadows, the more textures and the more area lights and area shadows you have the lower the settings need to be to get a smooth result, with only about ten area lights and shadows in many scenes you can reduce the settinsg down to 10% - 20% accuracy and the samples right down and still get a very clean result. For animation though you'll need to keep the settings a little higher to avoid noise.

Taxman9
01-11-2007, 12:15 AM
Okay, thank you for that clarification, I guess I was misinterpreting your post, and comparing apples and oranges, well thinking I was comparing apples and apples.

Thanks again
Josh

loureed
01-11-2007, 09:56 AM
sorry to jump in (this is for Jazztastic).
My exterior scene file is here, http://www.c4dportal.com/forum/showthread.php?t=844
hope you like it :)

belushy
01-26-2007, 08:48 AM
Sorry there is actualy no better words in Vienniese german for your help / the leo dict will help to translate this

thank you so much for this very clear Tips

cheers belushy

anobrin
01-31-2007, 01:03 PM
4) Lack of post processing - Virtually no really good renders are the result of anything coming direct out of the render engine. If you want it to look good then start to play around with the image in Photoshop or After Effects, all the best images you see have fairly heavy post work from color correction to added grain and photographic style effects e.g. lens blurs, glows, artifacts, grains. Doing this extra step will drastically improve the overall result.



Bravo!!! Sir
A big reality of a Good CG is that postwork is Crucial!!

We all know that the movie "Final Fantasy TSW"
was a commercial failure. etc etc

But do your self a big favor

Buy a copy from the "bargain bin" at the video store or from a pawn shop
for 5 or 6 $USD and watch the extra content DVD!!!
you may be surprised at how much of that films effects and look
was achieved with good postwork

for example the visible helmet lights on the "deep eyes'
were simple elongated Cone primatives, parented to the head
and rendered in a separate pass and given that "hazy" light beam look in post

here are some simple compositing tests i did recently using..(GULP!!)
DAZ studio/poser carrara for the animated figures Artmatic voyager for the environment
and Autodesk combustion for the effects

were not talking the "defense of Helms deep" here
but the Comp methods im learning will help me in future efforts hopefully
as I am Now going back to a full C4D workflow using Interposer pro

thanks for all the tips ive printed your post to hard copy for a quick referenc

(My composites)

http://www.mediamax.com/wolf359/Hosted/hellfire.mov

http://www.mediamax.com/wolf359/Hosted/COMPOSITIONSFNL3IVX.wmv

*** Note these links are on temporary host. anyone here is welcome to rightclick/download
and rehost for the sake of discussion if you care to.

may you all have good renders !!!

caraffi
04-29-2007, 05:11 PM
Thanks Per for taking the time to share these w us :)

Skamierski
10-09-2007, 12:32 PM
a. Details->Contrast set to -50%


i could hug you for that tip

thanks :thumbsup:

Dtox
10-19-2007, 09:34 AM
This thread is freakin amazing!

Using the info here, I went back and improved some old scenes that I'd long since abandoned.
That contrast -50% is great.

I need MORE though!

What I'm wondering is if there's anywhere to get information that describes in depth (or not) what all the elements of the shaders do.
There are alot of parts of shaders that I don't mess with because I simply don't know what they do. And I don't know how exactly to find out what they do except using trial and error.
And that I do, but more often than not it has disastrous results.
It would be great if there were documents or tutorials out there that explain what some of the more complicated functions are.
Stuff like attenuation and what not that have numerical fields. When I adjust these fields, it often ruins everything because if you adjust it too little, you can't see how it effects anything, adjust it too much and you ruin your entire shader.
And when you have a scene using GI, it's not practical to keep re-rendering a scene after every minor adjustment when it takes 2 hours or more to render.
Using render region helps, but it's not an overall solution since certain things effect other parts of the scene.
I've done some searches to see what's out there, but I can't really find anything useful.
I just don't know where to find this information

tarot
01-04-2008, 06:48 PM
Per, thank you so much, you've clarified a lot of my understanding of why reneders can look so poor.

adrencg
08-23-2008, 05:14 PM
Excellent tips and advice... should be in the C4D manual!

This is just general good advice for any software. I can use this advice in XSi as well.

Krodil
02-24-2009, 05:42 AM
Is the settings on page one and 2 still usefull with version11 or whats new.. the thread is old :)

ondertenonder
11-02-2009, 04:23 PM
The contrast -50% trick is one of the best simple tips on lighting in c4d i've ever come across.

should be the default setting. Or whenever more than 1 light is in use should automatically jump to this.

ahven
11-09-2009, 06:17 PM
Shadows. If you use basic renderer never use default 100% shadow density. Lower the value depending on lighting conditions into 70-80%. This does not give you too dark shadows in renderings.

nicolasdangelo
11-21-2009, 03:16 AM
thanks very much for your suggestions.
i believe it's good to experiment with all settings and see results in order to learn, but it is much more reassuring to do so with a thorough list like yours as a point of reference.

StageDiz
01-27-2010, 01:02 PM
Pretty thread! Very-very usefull. Thanks guys! :applause:

Per-Anders
01-31-2010, 08:18 PM
Shadows. If you use basic renderer never use default 100% shadow density. Lower the value depending on lighting conditions into 70-80%. This does not give you too dark shadows in renderings.
I don't see how that would ever make for good renders, instead it will create washed out very CG looking renders.

If you want to make the effect of global illumination you should use global illumination or careful placement of bounce lights, reduced opacity for light shadows is something that should be used very sparingly and only in situations where there's no feasible alternative to getting enough light into an area. In fact given compositing there's really very little need to ever use it as you can adjust the shadows in post.

More or less most of the options that allow for non physically correct renders with lights can be considered as artistic choices, they should be used when you are after a certain look rather than enabled as a rule, for instance shadow color, colored falloffs and so on. You need to evaluate each and every light differently in these cases and determine it's impact on the scene and whether it needs these effects or not to get the result you're after. In certain circumstances you may well find you need or want to reduce the shadow opacity, but it should never be the rule.

It's very important to use artistic judgment for everything, consider it the rule of the devil in the details - the more detailed a focus you give to each area and the overall image, the less you depend on "rules" and the more direct control you have over every detail which results in less sloppy and generally better renders, the trick is to work out what you can get away with not having to adjust individually so that the image can be "finished".

rodrigobarbosa
02-28-2010, 01:40 AM
REALLY helpful thread!
thanks guys

SmedleyX
01-31-2011, 06:34 AM
Great thread, keepin' it active!

ahven
04-26-2011, 05:34 PM
I don't see how that would ever make for good renders, instead it will create washed out very CG looking renders.

If you want to make the effect of global illumination you should use global illumination or careful placement of bounce lights, reduced opacity for light shadows is something that should be used very sparingly and only in situations where there's no feasible alternative to getting enough light into an area. In fact given compositing there's really very little need to ever use it as you can adjust the shadows in post.

More or less most of the options that allow for non physically correct renders with lights can be considered as artistic choices, they should be used when you are after a certain look rather than enabled as a rule, for instance shadow color, colored falloffs and so on. You need to evaluate each and every light differently in these cases and determine it's impact on the scene and whether it needs these effects or not to get the result you're after. In certain circumstances you may well find you need or want to reduce the shadow opacity, but it should never be the rule.

It's very important to use artistic judgment for everything, consider it the rule of the devil in the details - the more detailed a focus you give to each area and the overall image, the less you depend on "rules" and the more direct control you have over every detail which results in less sloppy and generally better renders, the trick is to work out what you can get away with not having to adjust individually so that the image can be "finished".

Perhaps my opinion was too limited. This is oldschool and totally bad way of faking the way out with shadow opacity.
After I have read some more in Jeremy Birns Digital Lighting and Rendering book I have realised couple of things.
One should always balance things in lighting and not try to fake them out as with shadow opacity.
Itīs possible to use heavy shadow and then balance the scene with fill lights and Inverse Square lights added in right position and with correct falloff amount. Using the GI and lights is a hybrid method and I agree that the light intensity must be quite low when using lights with that. Of course itīs a good way to use light emitting GI surfaces too.

What comes to new R12 thereīs LWF but I was not very happy with it. It is flattening the image all the way. There was even more flexibility with old color mapping method. LWF is not looking always convincing.

AO or Ambient Occlusion
For example the darkest area of shadow should be totally black when an object connects to a surface. Also tight corners and creases should have more darkness than surfaces that are more round. This extra shadow darkness can be achieved with Ambient Occlusion that gives the extra detail.
However in real world it is fake if every object has got a same amount of AO.
In CG and in Cinema 4D this can be adjusted separately in material level with each material that can have itīs own AO value.
With large scale projects such a buildings and houses you should have the AO render pass with separate file and this should be rendered at the latest when all the model details are in place.

Rendering with AO in the same scene will make render time longer and on the other hand you should always render AO in a separate pass and composite in Photoshop.

Bondoman
05-02-2011, 02:13 PM
Hey Per-Anders!

I just read through this whole post, absolutely awesome tips! thanks alot :bowdown:

- Though, I would like to know if it was possible to get an updated view on the "steps" you made for setting up default stuff. since I am guessing none of that stuff works well with R12 and linear workflow and well all the other updates. I would really appreciate it! :beer:

Bondoman
05-02-2011, 02:16 PM
Oh yeah, I forgot 1 question.

Omni vs. Area and spotlight - I allways use omni lights since thats what i know how to use, just like I allways used the phong for everything. got any tips on that? :)

mathiasberglund
07-10-2011, 07:30 PM
Unsure if it has been mentioned, but I tend to make the ao-gradients go from darkblue to white instead of black-white to support/compliment blue light in outdoorscenes.


edit: I'm slightly unsure if this tip is regarded as a "shouldn't". I've used this method in together with ambient occlusion sucessefully - to my own taste - previously (back in 3d after a three year break). However I can imagine it results is some extra / unwanted adjustments in post if you want to go towards a warmer tones in colorcorrection/post.

Skyknight
10-20-2012, 02:15 AM
Thanks a lot for the class :applause: I love learning new things to help me get a lot better :D

Skyknight
10-20-2012, 01:14 PM
Thanks a lot for all of these helpful tips, speeding up my renderings is a lot of help.

Thank you very much :D

caltd
02-06-2014, 03:20 PM
Hi Per-Anders,

Thanks for the tips - and thanks to the rest of you who've contributed.

Wondering how you might change this list in considerations of the later updates and advancements in R15 - your original post was in 2006!

Specifically, it seems there would be some changes due to the implementation of linear workflow and the physical renderer, but I'm sure there's other areas in which you've updated.

Any tips & tricks you can share today? Updates to your setup?

Thanks again!
-Cx


As an addition to this here's the steps involved in order to keep Cinema set up with reasonably optimal settings every time:

To set up your render settings and scene:

1) File->New...
2) Render->Render Settings
a. General->Name (give any name you want for this preset).
b. Save->Depth set to 32 Bit/Channel
c. Antialiasing->Filter set to Sinc
d. Effects->Post Effect->Color Correction, set Gamma to 1.8/2.2
e. Effects->Post Effect->Sharpen Filter, set Strength to 10%
f. Options->Ray Depth, reduce to 6, Shadow Depth reduce to 6 (speed increase).
g. Save Menu (in render settings window, not Save Tab), Save->Save Render Preset
3) File->Save As... save in Cinema4D application directory as "new.c4d"

To set up your materials and lights:

1) Create a new material (Materials Manager File->New Material), then in the attributes manager...
a. Illumination->Model set to Blinn
b. Click on Color Tab again
c. Attributes Manager Menu : Edit->Set As Default, click Yes to confirm
2) Create a new light (Objects->Scene->Light)
a. Details->Contrast set to -50%
b. Details->Falloff set to Inverse Square (optional)
c. General->Shadow set to Shadow Maps (soft)
d. Shadow->Absolute Bias, uncheck
e. General->Shadow set to Area
f. Shadow->Accuracy set to 50% (speed up!)
g. Shadow->Maximum samples set to 64 (speed up!)
h. General->Shadow set to off
i. Attributes Manager Menu : Edit->Set As Default, click yes to confirm

And that's it. Now every time you create a new material it will be using Blinn as default, every time you create a new light it will have inverse square falloff and a better contrast, and every time you create a new scene it will have the sharper and unclamped AA, gamma correction and sharpen enabled by default, and hopefully this should help you improve the overall quality of the renderings you create.

Similarly to this you may wish to reduce the "delta" setting in several of Cinemas shaders by default and again use a "Set as Default" to store the sharpened up shaders so that next time you use them in your bump channel you will end up with suitably crisp bump maps.

Happy rendering.

Decade
02-22-2014, 01:28 AM
I'm not Per but I can answer a few of these:

- a. Illumination->Model set to Blinn - is the default nowadays, no need to set.

2) Create a new light (Objects->Scene->Light)
a. Details->Contrast set to -50%
b. Details->Falloff set to Inverse Square (optional)
c. General->Shadow set to Shadow Maps (soft)
d. Shadow->Absolute Bias, uncheck
e. General->Shadow set to Area
f. Shadow->Accuracy set to 50% (speed up!)
g. Shadow->Maximum samples set to 64 (speed up!)
h. General->Shadow set to off
i. Attributes Manager Menu : Edit->Set As Default, click yes to confirm

This describes setting up a reasonably physically accurate light with optimised render times as the default light. If using physical render, some of these settings will now be taken out of your hands & tied to the overall sampling settings in physical render, thereby reducing the number of settings you need to use.
Personally, I would now only do steps, a), b), e) & i)

One instance where I wouldn't use b) is a sun or moonlight. Since these lights are coming from 1000s of miles from outer space, they are not going to visibly falloff across your scene. They should be made as infinite lights with no falloff.

A good rule of thumb is if you can see the light source in your scene (ie a lightbulb, torch, fire, etc) it should have inverse square physically accurate falloff. If it's a distant light like sun, moon, or the refracted light from the sky (ie an ambient light representing the sun's light scattered through clouds & the atmosphere) it should have no falloff ( But still a shadow).

d. Effects->Post Effect->Color Correction, set Gamma to 1.8/2.2
I would not apply this as blanket setting anymore. In fact I wouldn't use this setting at all. Linear workflow comes checked by default nowadays, if you don't like the light balance you get after this, you can add the post effect > colour mapping with default settings & up the dark multiplier to bring up the dark areas.

The notes about sharp bump maps apply to stills work. The last thing you want for animation is very sharp bump maps - they are going to fizz or sparkle.

Re AA - I guess Sync is still about & fine I guess. I think now most will use still setting & apply any softening in post. I think the thinking nowadays is produce the sharpest image from the CG & soften in post if need be.