Author Topic: Personal Tutor for Corona for C4D Rendering  (Read 1506 times)

2023-01-06, 01:21:16

kmwhitt

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I hate to admit that I’ve been using Corona for C4D for several years now and I have yet to achieve any quality renderings.  I’ll spend hours changing materials, render settings, and post-production to no avail.  I always end up with a murky, gray, hazy result (example attached) – not the crisp clear images others are producing.  This is a link to the type of images I hope to produce:

https://rebusfarm.net/blog/3797-the-making-of-bedroom-by-white-balance

To say the least, after so many years this is disheartening…

I am quite familiar with Corona as I’ve been using it for so long (obviously incorrectly).  I won’t need anyone to go through the basics.  I’ve also been a C4D user for almost 20 years, so I know my way around the software and am quite familiar with various rendering engines.  I was a Vray user prior to Corona and achieved the same subpar results.

It has only come to my attention recently that I can increase material values above 70% and that you’re in the “safety” zone if not exceeding 90%.  I’ve been using this 70% cap as I was taught incorrectly when Vray was first introduced to Cinema 4D.  To make matters worse the earlier versions of Vray for C4D were glitchy in the way materials and light were calculated – as some users may remember.

As our firm creates mostly kitchen and bath design, we work in inches.  I have often wondered if Corona isn’t converting the units correctly as some of the light settings need to be lowered substantially to avoid over-exposure.  An example would be having to set under cabinet lighting to 50 lumens or less in an LED strip span of 5’ which is not realistic or 25 watts of fill light blowing out the entire scene.  Further, none of the PBR materials I create in Substance look the same as they do in Substance.  I always must adjust glossiness/roughness and base color considerably.

Due to my suspicions of the units not converting correctly, I would at the very least appreciate someone trying the scene for themselves.  I will upload upon request.

I am looking for a C4D user who is capable of stunning results to tutor me.  I thought it would be a good idea to use the file from which the attached image was produced as an example scene – hopefully having someone walk through/dissect the scene and tell me where I’m going wrong.  I am willing to pay well for your time.  Please PM me if you’re interested.  I work from home so I can be flexible with the hours.  Thank you.

2023-01-06, 23:02:34
Reply #1

Stefan-L

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well it is just my opinion, but this is what i think could make the image better:

1) the materials look not really good yet, several textures are not realistic, the wood of furniture and floor are in bad in scale, to big and too small on floor, the tiles look artificial and unreal,  (partly also bad textures. in my eyes textures made in substance tends to look often unreal for architectur) better use good quality bitmaps etc, built/tune the shaders in c4d -we also make mats with our inhouse tools in c4d, always from real photos/photoscanes (we us tools like q-tilepro, but you can also use psd.)

the reflections of the materials seem not good, sometimes to shiny, too strong. reduce the default ior of the new physical material for most real world materials. 1.6 is too much for most things.

the gold looks overexposed, add imperfections to break up highlights and reflections

see the mapping is made better, like the marble on the sides or the wood on the chair show issues

2) the light seems unbalanced and not so generating a nice mood. too much light is coming from the camera direction. the lights on the left seem to bright for the image and get too important. try to build up a hierarchy on the light sources to generate a nice and balanced mood. shadows and contrast are very important for an image.
try to think like a photographer

3) use tone mapping. usually no more post production is needed if the render is good. use contrast and curves, maybe the new ACIS OT or, for sure nice LUTS. we also always use the curves to fine tune the exposure and look. try to avoid or minimize post production.(maybe only some light room like tunings if at all)

best
St.
« Last Edit: 2023-01-08, 21:57:34 by Stefan-L »

2023-01-11, 20:27:33
Reply #2

kmwhitt

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Stefan - thanks for the helpful reply.  I apologize for not responding earlier.  I thought I had ticked "notify" but not the case I guess.  I will take your suggestions and see what I can come up with.  Thanks!

2023-01-12, 14:54:19
Reply #3

Maybejensen

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I hate to admit that I’ve been using Corona for C4D for several years now and I have yet to achieve any quality renderings.  I’ll spend hours changing materials, render settings, and post-production to no avail.  I always end up with a murky, gray, hazy result (example attached) – not the crisp clear images others are producing.  This is a link to the type of images I hope to produce:

https://rebusfarm.net/blog/3797-the-making-of-bedroom-by-white-balance

To say the least, after so many years this is disheartening…

I am quite familiar with Corona as I’ve been using it for so long (obviously incorrectly).  I won’t need anyone to go through the basics.  I’ve also been a C4D user for almost 20 years, so I know my way around the software and am quite familiar with various rendering engines.  I was a Vray user prior to Corona and achieved the same subpar results.

It has only come to my attention recently that I can increase material values above 70% and that you’re in the “safety” zone if not exceeding 90%.  I’ve been using this 70% cap as I was taught incorrectly when Vray was first introduced to Cinema 4D.  To make matters worse the earlier versions of Vray for C4D were glitchy in the way materials and light were calculated – as some users may remember.

As our firm creates mostly kitchen and bath design, we work in inches.  I have often wondered if Corona isn’t converting the units correctly as some of the light settings need to be lowered substantially to avoid over-exposure.  An example would be having to set under cabinet lighting to 50 lumens or less in an LED strip span of 5’ which is not realistic or 25 watts of fill light blowing out the entire scene.  Further, none of the PBR materials I create in Substance look the same as they do in Substance.  I always must adjust glossiness/roughness and base color considerably.

Due to my suspicions of the units not converting correctly, I would at the very least appreciate someone trying the scene for themselves.  I will upload upon request.

I am looking for a C4D user who is capable of stunning results to tutor me.  I thought it would be a good idea to use the file from which the attached image was produced as an example scene – hopefully having someone walk through/dissect the scene and tell me where I’m going wrong.  I am willing to pay well for your time.  Please PM me if you’re interested.  I work from home so I can be flexible with the hours.  Thank you.
Also, remember to set all maps that aren't diffuse, to gamma 1.0. I think that should make them look more like what you see in substance
MAYBEJENSEN I Working on something I  Ryzen 3950x / RTX 3080

2023-01-12, 15:18:38
Reply #4

kmwhitt

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Maybe - thanks for the input.  Is this all maps (including normal) or just those out of Substance?

2023-01-20, 16:29:05
Reply #5

ant1dp

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Im looking for a teacher too.
Master Photoshop Retoucher
Learning Photorealistic 3D

2023-01-21, 07:57:49
Reply #6

3DInteriors

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Some very good basic tutorial here.  3DS MAX + Corona , but the Corona Render is same.
You'll understand if you watch it. Watch a lot of videos and the rendering will be much better


https://www.youtube.com/playlist?list=PL7nKaHOxkqDsZCnWrqEVw_lI524SwSGYn

2023-01-21, 13:27:45
Reply #7

burnin

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One eager to learn can not simply ask a video tutorial to answer whatever, whenever an issue comes to mind, neither does it help when specific tasks are at hand.  It's then rather easy to lost flow of thought and thus hard to efficiently spend dedicated energy... 

I'm starting to think time has come... for, if there's enough interest, it may be good to get 'together' and make sort of short-term "academy" specifically tailored for C4D users, since when it comes to details lots of stuff is done and works quite differently compared to 3DS Max... 

2023-01-21, 20:53:32
Reply #8

James Vella

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A key thing here is to note that not everyone comes from a 3D background or understands how to 'easily apply knowledge from one software to another'.

Some people are short on time, they have a specific goal - to create photographic renders in their 3D application of choice.

Most of us have a large resource of videos/images/books we learned from but those who require specific knowledge in a short frame of time are asking because they have probably already been down the 'youtube' path and need specific direction to their goal. To be honest its hit and miss on youtube and those who are requesting this information are obviously industry professionals in their own right and are actually looking for a teacher/coach who can build their experience in a shorter amount of time for 3D purposes - thus the request for paid tutors.


2023-01-22, 23:07:43
Reply #9

jojorender

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I agree with James that getting a tutor can be a good thing but there might not be a shortcut to learning photography fundamentals.
Besides Stefan’s great feedback about your materials and lighting, the most important advice he gave is the one probably easiest to be overlooked.
try to think like a photographer
At the end of the day we are all just photographers that use a mouse instead of a camera.
Mastering a render engine is only half the battle. Photographic composition, lighting, etc are equally if not more important.

@kmwhitt
Ditch your mouse for a day and use your camera to photograph your own kitchen like a pro photographer would do.
What time of day do you get the best natural light? What is your main light? Do you need fill? What’s the most interesting angle? Etc…
The importance of real life reference images can’t be overstated. Don’t look at renderings as a goal to achieve, look a real life images if photorealism is your goal!!!
Many years ago I came across Peter Guthrie’s website and his scrapbook section was a real eyeopener. http://www.peterguthrie.net/scrapbook.
Collect every amazing real life kitchen photo you can find and really look at them and find out why you like them. Look at appliance manufactures images - sorry, probably mostly renderings ;-)
Look at your reference collection before starting every job,,,,

Back to Corona:
Materials: Less is more! Don’t get distracted with a gigantic material library. Concentrate  on building a few great simple everyday materials. Forget about substance, get some hi-end pbr textures and find out their real world scale. When I get material samples from architects or manufacturers, I always ask that they place a ruler next to the sample so I get the real scale. In C4D you can put a placeholder plane with the exact material sample dimensions to judge how your real life material sample maps in the scene. Makes sense? 
I use a furnished/ lit room to test out new materials to get some “real” reflections.
Test your mat on the real object, a cube tells you very little how a material behaves.
Render closeups, but be aware of the blur scale issue when further away.
Great textures make a HUGE difference.

Geo: Bevel everything!!! Where not possible use rounded corner shader.
Build your most used floors in real geo, bevel and space for grout etc. Use a couple of great wood/ tile textures, randomize and rotate for variation. It’s worth spending time on key objects to reuse in future projects.
 
Lighting:
I see a couple of (windows/ area lights?) reflections in the island lamps.
What is actually behind the camera? Make sure the room is always “complete” - bounce and reflections are very important.
I would:
- Delete ALL lights in your scene.
- Use material override in render settings to clay render the scene (preserve window glass)
- Use sun and sky for simplicity.
- Place sun to shine into window on the right, in a nice and realistic angle. Adjust sun size for softer shadows.
- Render and tone map to find your exposure value. Adjust EV, highlight compression, contrast/ curves till you have a good overall exposure just from the sun entering the room.
- Add lights that exist in your scene as 3D models (no “invisible” fill lights). Adjust their brightness to fit your established exposure. The under-shelf lights are too bright!
- If the scene is too contrasty, create masks for elements that are blown out / too dark.
- Map your new materials, turn off mat override and test render. 
- I save out several exposures EV 0, EV+2, EV-2 and use the masks, brush, etc to combine in Photoshop. This gives me better control than placing a bunch of fill lights into the scene. If you really need fills maybe lightmix could also give some flexibility…

Some tips you might already know:
I sometimes use ray switcher on wooden floors to control color reflected back into the room/ ceiling.
Use legacy mat for glass to be able to control reflection strength if necessary     
Important! NEVER use fill lights to just throw more light into a room. If absolutely necessary use fills to model edges / shapes.

Instead of just watching 3D YT videos, watch how photographers light rooms and apply that in 3D.
Most important: Look at your REAL LIFE reference images!

Hope this helps.
Post a update when you made some progress!