Twilight Render User Forum

Hello friends,

Are there any good advanced tutorials out there? I’ve been using twilight for about three years now and I’ve done the tutorials on Lynda.com. So ideally something that beyond those.

Thanks,

Maarten

Hi Maarten,
Do you have specific areas in which you are interested/need tutorials?
Have you been through all our video tutorials? (link in my signature)
and all our tutorials on our website? (link in my signature)
Have you been through all the Tutorials/Tips and Tricks?

Hi Fletch,

Sorry for the late reply, but I wanted to make sure to watch all the video tutorials first. They were very helpful, I learned a lot. But if I may offer some feedback:

I do feel that sometimes they just show you particular examples, without really expanding on them or explaining them properly. It is hard to find tutorials that give you context. e.g. Why does this deep material setting work better? Instead of just telling me that it does.

I also felt that the first video is actually the hardest one. It took me a long time to get the water and glass effects.
This was also caused by the info being outdated since the latest releases. So maybe it's time for an update

One thing I also wonder about: it is mentioned that it's better to pump up the exposure in your render post process instead of increasing the power of your lights in a scene. If it is your job to actually propose a good lighting plan then that sounds like a bad plan. Wouldn't it be better to add more (powerful) lights to your interior so it is properly lit? I also find that areas get overblown if you increase the exposure.

Cheers,

Maarten

Hello Maarten,
Thank you very much for your thoughtful response.

Yes, Twilight Render V2 has developed over time, adding, most importantly perhaps, auto-templates. Meaning that default SketchUp water textures all have a default rendering "look" for Twilight, and you don't need to touch them at all. Same with the glass materials... and any material with a texture file.

We probably should, as a result, create a new "getting started" based on the Tadao Ando scene. But with that major exception it still covers nearly everything one needs to know to get a great jump into Twilight Render.

One thing I also wonder about: it is mentioned that it's better to pump up the exposure in your render post process instead of increasing the power of your lights in a scene. If it is your job to actually propose a good lighting plan then that sounds like a bad plan. Wouldn't it be better to add more (powerful) lights to your interior so it is properly lit? I also find that areas get overblown if you increase the exposure.

This is a simple question of physics. Twilight Render is based on the actual physics of light and materials, so setting the lights and materials properly is critical for good results. This is the same in all good render engines.
Therefore, the camera, and setting the camera exposure, is critical in Twilight just as it is in all great render engines. We did our best to keep it simple, (you should have seen what we used to have to do to tweak the camera settings way back in the day). So since your light it going to bounce off of the surfaces with materials and eventually reach the camera, artificially boosting the power of the light fixture is literally breaking something that is already fixed. Simply boost the exposure, just as in real life with real camera exposures with interior photography. Architectural photographers and realtors all know that lighting is critical to their shot. They may add an "artistic" or "tastefully placed" fill light every now and then, but they don't change the light bulbs in the space. They simply increase the exposure of the camera.

Saving the rendered image in HDR format and tone mapping in an external image editor is completely legitimate - just as in real photography.

The exposure *tone mapping* of your rendered image is extremely critical to getting satisfactory results.
Please see this thread which is a deep dive into the subject with real world photo examples:
Interior Renderings - Exposure for Background Outside

Hi Fletch,

Thanks for the information. I agree completely with what you say about exposure and as I do a lot of interior photography myself I am aware of the process.

What I was referring to was a situation where you want to create the right lighting plan for an interior space, rather than making a properly exposed visual. (9 out of 10 times I have to do the latter so I am very happy to learn that the option of raising the exposure is actually the better one. )

cheers,

Maarten

Too much/powerful lighting will result in errors and actually slow down the rendering and/or result in artifacts in the image such as noise and "fireflies" (little annoying white pixels that will not clear up) that are undesirable. The colors and materials/reflections will be wrong as well. Lighting is super important.

We suggest setting all lights to correct physical radius, and setting power according to actual Lumen output for that light fixture - find this info on the manufacturer's website.

Maarten, this is perhaps the most important thread about all the powerful features we've added to Twilight V2 making many of the old material libraries obsolete.

Everyone should read it carefully!
(It probably deserves a video all to itself)

Fletch wrote: ↑Tue Nov 06, 2018 11:25 am Too much/powerful lighting will result in errors and actually slow down the rendering and/or result in artifacts in the image such as noise and "fireflies" (little annoying white pixels that will not clear up) that are undesirable. The colors and materials/reflections will be wrong as well. Lighting is super important.

We suggest setting all lights to correct physical radius, and setting power according to actual Lumen output for that light fixture - find this info on the manufacturer's website.

Alright, good to know! So all the light fixtures in the resources area of the forum are good to go. Their power should not be altered, correct?

cheers,

Maarten

They should be good to go, but you of course can modify the power if you like. But base them on real-world numbers. So if you think it needs a 100 w incandescent, then set the light power to the proper lumens for that bulb type.