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Make Your Most Realistic Renders – Ever!
Posted: 06 September 2013 02:16 AM   [ Ignore ]   [ # 406 ]
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Dartanbeck - 05 September 2013 06:50 PM
PhilW - 05 September 2013 11:16 AM

Interiors have always been difficult with Carrara, but I think using gamma makes them a lot easier to get looking good.  I had a real issue with this scene, but I have now found a way forward. Rendered only in Carrara, with a little postwork just to add glows on the lights and an overall camera bloom using the virtualPhotographer plugin, otherwise untouched.  It would have rendered in around 45 minutes if I hadn’t used blurred reflections!

Wow. But the blurred reflections turned out so freaking cool! So, does ‘aura’ (just adding a slight amount is all I ever do) work okay with GC=2.2? Just asking because of the post work comment.

Yes it does look good!  Yes Aura and other Carrara post-effects would still work, but I prefer the control of doing that kind of thing in post, at least for a still image.  It can be very frustrating to have rendered a great image for hours, only to have it ruined because the Aura or other effect has the wrong settings. It would be great to have these interactive on the final image as can be done with Luxrender.

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Posted: 06 September 2013 02:28 AM   [ Ignore ]   [ # 407 ]
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PhilW - 06 September 2013 02:11 AM

If you are going for realism, which I usually am, using spots and bulbs in Carrara (and yes, maybe other programs as well) is an issue in itself, as the light does not fall off according to an inverse square law as it should, but falls off linearly.  Why are they not physically correct?  .

Why don’t you use anything glow family light (including shape lights). I always do (when not using photometric lignts) because there is a inverse square falloff.

I believe that this is one of the under used features of Carrara.

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Posted: 06 September 2013 02:49 AM   [ Ignore ]   [ # 408 ]
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Philemo - 06 September 2013 02:28 AM
PhilW - 06 September 2013 02:11 AM

If you are going for realism, which I usually am, using spots and bulbs in Carrara (and yes, maybe other programs as well) is an issue in itself, as the light does not fall off according to an inverse square law as it should, but falls off linearly.  Why are they not physically correct?  .

Why don’t you use anything glow family light (including shape lights). I always do (when not using photometric lignts) because there is a inverse square falloff.

I believe that this is one of the under used features of Carrara.

You are right that these can be set to have the correct fall off but they still have issues for me - for example by default they still produce hard edged shadows and the shadow softness is unrelated to the size or shape of the light object.  I have taken to using brightly glowing objects with full indirect light, which appear to be more physically correct. This is the equivalent of using a mesh light in Lux.

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Posted: 06 September 2013 03:16 AM   [ Ignore ]   [ # 409 ]
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Falloff has no physical existence. As the distance from the source increase, the potential surface covered by the light increase. The same quantity of light for a bigger surface means less light for a particular point. The ratio from distance to surface is of square magnitude (as ratio from distance to volume would be of a cubic magnitude), thus the inverse square law. At a distance, there won’t be enough light for human eye (or virtual camera) to see it. But there will be light. That’s why I say it has no physical existence, it’s just a matter of perception.

The good way to specify a source light would be to specify power. The program should be able to do the rest of the math, instead of asking to poor end user to do it grin. I use to have an excel file to do the conversion for me. I don’t know where it is, but I’ll see if I can find it again.

I’ve done a lot of experiment with soft shadows… Including physical deflectors. I don’t have a general rule except adaptation to the particular scene.

I will try glow in full indirect lighting.

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Posted: 06 September 2013 03:46 AM   [ Ignore ]   [ # 410 ]
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Use the 0-10000% parameter in the glow channel.  If you want a coloured light, use the multiply operator with a colour (or other source!).  And if using a simple plane, make sure that the surface normal is facing the way that you want the light to go, there are nasty digital artifacts if you use the wrong direction!

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Posted: 06 September 2013 11:05 AM   [ Ignore ]   [ # 411 ]
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PhilW - 06 September 2013 02:11 AM

If you are going for realism, which I usually am, using spots and bulbs in Carrara (and yes, maybe other programs as well) is an issue in itself, as the light does not fall off according to an inverse square law as it should, but falls off linearly.  Why are they not physically correct?  I suspect because it looks better that way without gamma!  So in a sense, the whole program is set up to produce “nice” looking images without gamma, and with speed-saving features like ambient light.  Which makes it difficult to get that ultra-realistic look that today’s physically based renderers are capable of.  But there are a bunch of things that you can do to get around this and make Carrara behave in large part like a physically based renderer to achieve realistic results, but with the advantages of being able to use all of Carrara’s built-in features and a (relatively) fast renderer.

I wasn’t suggesting anything about the physics of the light. As you know, Carrara is an art program, not a physics program. I was pointing out that it’s not fair to single out Carrara and say it has a hard time with indoor lighting, as I’ve seen plenty of crappy indoor lighting renders from other programs. As with most things, it’s the skill of the artist. That beings said, even the most skilled artists have their weak areas. Mine tend to be night scenes, so I tend to try and work on those from time to time.

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I find it somewhat liberating not to be encumbered by accuracy.

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Posted: 06 September 2013 11:13 AM   [ Ignore ]   [ # 412 ]
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evilproducer - 06 September 2013 11:05 AM
PhilW - 06 September 2013 02:11 AM

If you are going for realism, which I usually am, using spots and bulbs in Carrara (and yes, maybe other programs as well) is an issue in itself, as the light does not fall off according to an inverse square law as it should, but falls off linearly.  Why are they not physically correct?  I suspect because it looks better that way without gamma!  So in a sense, the whole program is set up to produce “nice” looking images without gamma, and with speed-saving features like ambient light.  Which makes it difficult to get that ultra-realistic look that today’s physically based renderers are capable of.  But there are a bunch of things that you can do to get around this and make Carrara behave in large part like a physically based renderer to achieve realistic results, but with the advantages of being able to use all of Carrara’s built-in features and a (relatively) fast renderer.

I wasn’t suggesting anything about the physics of the light. As you know, Carrara is an art program, not a physics program. I was pointing out that it’s not fair to single out Carrara and say it has a hard time with indoor lighting, as I’ve seen plenty of crappy indoor lighting renders from other programs. As with most things, it’s the skill of the artist. That beings said, even the most skilled artists have their weak areas. Mine tend to be night scenes, so I tend to try and work on those from time to time.

Yes, I’m not singling out Carrara, but it is the program I know my way around the best. I have no doubt that many other programs do a worse job than Carrara, and even the best programs can produce so-so renders!

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Posted: 06 September 2013 02:39 PM   [ Ignore ]   [ # 413 ]
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Thanks PhilW for sharing this information. I appreciate all info that can improve the Carrarra rendering.grin


https://www.facebook.com/pages/Ricor/515417181836687

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Posted: 06 September 2013 03:11 PM   [ Ignore ]   [ # 414 ]
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Right. That video explanation of Gamma Correction/Linear Workflow used the difficulty of creating stunning indoor renders as the subject of interest towards explaining the idea around Gamma Correction, which has nothing at all to do with Carrara - just 3d rendering in general. I really enjoyed that video, too. Maybe I’ll watch that again while I wait… and wait… lol

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Posted: 07 September 2013 01:40 AM   [ Ignore ]   [ # 415 ]
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This is a work on progress. I’m trying to figure out what will improve picture realism.
The only lightning in the scene is sky light (110%) and full indirect light (80%).

It seems that Carrara’s default setting are not the ones to use when it comes to realism.
The default values tend to create sharp images and objects seem to have hard edges, not what you want for realism.

Some of the things I’ve found so far:
1) PhilW wonderful advice about the gamma correction: I’ve used 1.8, but finding the correct value is a key factor (I’ve tried 1.4 to 2.2).
2) AntiAliasing set to ‘good’ - seems to give better results than ‘best’, as it blurs the textures a bit.
3) Object accuracy set to 4. It seems that what Object accuracy does is to change the blur of the textures. Setting it to lower values like 1-0.5 hurts realism as it makes the textures too crisp (It seems that lower values are proper for realism only when the picture is very small, so the size of the picture is a factor to consider).
4) Shadow accuracy set to 4.
5) Filter sharpness set to 0. I’ve always increased it to 100% assuming it will improve quality. However, this is not the way to go, as it creates hard edges. You want your objects to blend with one another and with the background, so value of 0 seems to work best.

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Posted: 07 September 2013 02:15 AM   [ Ignore ]   [ # 416 ]
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Very cool! Not just the very nice image, but I always love a nice analysis of how you’ve come to the settings that you’ve used to create the image. But then, after reading that - and coming back to gaze at the pic some more, I really like it.

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Posted: 07 September 2013 02:51 AM   [ Ignore ]   [ # 417 ]
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This does have a nice realism about it, and the softness that you have created with your settings definitely contribute to that - good exploration!  You don’t mention ambient lighting but I assume that you have this set to zero?

The only other suggestion is to look at camera artifacts and grading.  Renderers such as Luxrender allow you to select from a variety of film responses and to add camera bloom, glare and other effects typical of photographs. I have found the Photoshop plugin virtualPhotographer to be excellent at applying these type of effects - as a start point, try the “Ambience” filter and then use “Fade” to knock it back to 20-30%. As well as adding a camera-like bloom, it increases contrast a bit and adds a little warmth too.  But I’m sure you will continue to experiment to achieve the look you are after.

You can add “aura” and “glare” etc within Carrara itself to mimic these effects, and I would use these for animations, but for stills, I prefer the interactivity of using Photoshop.

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Posted: 07 September 2013 04:39 AM   [ Ignore ]   [ # 418 ]
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PhilW - 07 September 2013 02:51 AM

This does have a nice realism about it, and the softness that you have created with your settings definitely contribute to that - good exploration!  You don’t mention ambient lighting but I assume that you have this set to zero?

The only other suggestion is to look at camera artifacts and grading.  Renderers such as Luxrender allow you to select from a variety of film responses and to add camera bloom, glare and other effects typical of photographs. I have found the Photoshop plugin virtualPhotographer to be excellent at applying these type of effects - as a start point, try the “Ambience” filter and then use “Fade” to knock it back to 20-30%. As well as adding a camera-like bloom, it increases contrast a bit and adds a little warmth too.  But I’m sure you will continue to experiment to achieve the look you are after.

You can add “aura” and “glare” etc within Carrara itself to mimic these effects, and I would use these for animations, but for stills, I prefer the interactivity of using Photoshop.

Ambient lighting - this little devil - was 20%. I’ve set it now to zero and I’m happy to see that it seems better than before.
(Usually I set it to zero, but its easy to forget all about it).
I’m doing some more experiments, and maybe I’ll take the sharpness up a bit.

I don’t use Photoshop, but rather Paint-shop Pro, do you know of something equivalent for PSP?

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Posted: 07 September 2013 07:32 AM   [ Ignore ]   [ # 419 ]
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Eyos - 07 September 2013 04:39 AM
PhilW - 07 September 2013 02:51 AM

This does have a nice realism about it, and the softness that you have created with your settings definitely contribute to that - good exploration!  You don’t mention ambient lighting but I assume that you have this set to zero?

The only other suggestion is to look at camera artifacts and grading.  Renderers such as Luxrender allow you to select from a variety of film responses and to add camera bloom, glare and other effects typical of photographs. I have found the Photoshop plugin virtualPhotographer to be excellent at applying these type of effects - as a start point, try the “Ambience” filter and then use “Fade” to knock it back to 20-30%. As well as adding a camera-like bloom, it increases contrast a bit and adds a little warmth too.  But I’m sure you will continue to experiment to achieve the look you are after.

You can add “aura” and “glare” etc within Carrara itself to mimic these effects, and I would use these for animations, but for stills, I prefer the interactivity of using Photoshop.

Ambient lighting - this little devil - was 20%. I’ve set it now to zero and I’m happy to see that it seems better than before.
(Usually I set it to zero, but its easy to forget all about it).
I’m doing some more experiments, and maybe I’ll take the sharpness up a bit.

I don’t use Photoshop, but rather Paint-shop Pro, do you know of something equivalent for PSP?

If you use Windows, there is a standalone version of that plugin, but I know they don’t do a Mac version. (http://www.optikvervelabs.com/)  It does say that the plugin is compatible with PaintShop Pro, so that could also be worth a try.  A huge range of great effects - I’m not generally a big fan of filters, but these are really useful for processing rendered images.

The other way to do a camera bloom effect (you may have seen something like this before) is to duplicate the layer, set layer blend to screen mode and apply a blur to the upper layer, and then back off the opacity to maybe 20-30% (but use your own judgement).

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Posted: 07 September 2013 08:21 AM   [ Ignore ]   [ # 420 ]
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Thanks for the feedback and for the tips! I’ll check about the plugin.
I’ve added some drama to the scene and a little bit of depth of filed.
I like it better now, I hope you do too.

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