kwhitt

@Ryan-M I’ve been experimenting with Chief’s PBR rendering engine for the last few months attempting to push it to its limits. Attached are images I produced for a master bath and PBR is quite capable with some postproduction work in Photoshop; however, there a few things missing that would really improve the realism: · The ability to change the phong angle of all components within a symbol. This is very important as many of the renderings I see contain objects with far too much smoothing causing artifacts during rendering. · The ability to control the cubic material mapping of objects in all three axes. Bitmaps can only be rotated on the Y axis which causes problems especially when applying tile materials to showers where the grout lines don’t sync. You can see this on countertops too where the texture on the front vertical edge does not align with the horizontal surface. If we could revolve/rotate the mapping in all three axes, this could be resolved. · The addition of pre-defined area lights so that it’s possible to accomplish many of the tricks used in interior photography. It can be done now by creating a flat plane and assigning an emissive material but it’s time consuming to move around in the scene. The area light would come in two forms – rectangular and disc-shaped. The rectangular lights would emulate studio light boxes and the discs would be used for ceiling lights with controls for fall-off. · The addition of a shader that mimics the rounding of corners for objects in the scene. Understandably so, Chief’s walls have sharp corners and having the ability to round them using a special bump map shader at time of render would add substantially to the realism and it would keep the file size down without all the added geometry. Models imported into Chief would not have to be as detailed and heavy with this feature. · The addition of penumbra to spotlights and point lights. There is no fall-off between shadow and light within the cone which is a dead giveaway. The addition of IES lights would also solve this problem. · The addition of anisotropy to simulate brushed metals realistically. Chief does allow separate roughness values for U and V, but I am unable to see where it makes any difference in my experiments. If only applicable to models with UV’s, there should be a cubic mapping option; however, this will only be useful if we are able to rotate around all three axes as mentioned above. · The ability to specify the IOR of dielectric materials. There is no way to differentiate between plastics, latex paint, and many other materials. Everything comes out looking like plastic with varying sheens. · The addition of sub-surface scattering (SSS) to stimulate plastics such as Lucite and other acrylics, marble, and milk, etc. · The addition of postproduction filters in Chief. At the very least, we should have the ability to control contrast or even better, a curves function such as that in Photoshop. Without this capability the images are flat and lifeless. It would also be nice to have more tone mapping options to prevent whites from blowing out a scene. I like ACES but it is a bit too strong, and it would be nice if we could limit its impact with a slider. · The ability to control door swing angle and opening status with Layer Sets. This would be a huge timesaver as I’m constantly opening and closing doors for different camera views. · The ability to control light attributes such as intensity and color via Light Sets. It is now only possible to specify whether a light is on or off. This can be a lot to keep track of – having to assign a Layer Set to each camera view that controls which of the lights are on and visible and at what intensity for each camera view. It’s somewhat doable now but a lot of work and clumsy. · The ability to control the extent of denoising with a slider and the radius of the correction. Often denoising is too much making the results blurry. Furthermore, small resolution images require a smaller denoising radius as the pixels are so few. I really hope Chief plans to expand the capabilities of their PBR engine as it has so much potential. Raytracing takes far too long, and the results aren’t nearly as nice as PBR. It would also be nice to avoid having to export entire projects to other rendering engines as you lose the parametric functions which work so well in Chief. If the developers could deliver on this, I could dispose of my other software.

Precisely!

@Ryan-MThanks Ryan - I'll get my most recent updated wish list and post it in this thread.

Thanks Rene. Will do. If we had the ability to prevent objects from casing shadows, I could make my own backgrounds which would have the same effect. There are so many things I'd like to see added.

@Ryan-M Ryan - Is there a way to use the HDRI as a backdrop only with no illumination? The illumination would come from a white color only. Thanks, Kevin

Thanks Ryan. Very helpful and it makes sense. Kevin

Ryan - Thanks for clarifying. Please see attached Light Data DBX. At the very top “Use Area Light(s)” is checked. With Light 1 selected at the top, you have the option at the very bottom to check “On in Default Light Set”. So, I assumed both types of lights were emitting or why have this option? It would seem to me that by checking “Use Area Light(s)”, the ability to select Light 1 would be grayed out. And Light 1 is shown to be used in “All Views” at the top. So, “All Views” at the top would apply to only non-GPU RT types of rendering? What happens if “On in Default Set” is not checked for Light 1? Will the area light still inherit the properties of Light 1 and calculate the emissive in lumens if the material’s "Apply Emissive and Color from Light(s)" is checked?

Thanks Renee. I find the Light Data DBX confusing for reasons I'll state in a separate post to Ryan. I've taken several interior courses on the use of Vray and Corona Renderer over the years from some well-known artists in those communities and they always speak of calibrating the scene for natural lighting first and then adding your interior accent lights (if appropriate). This way you know your exposure is using real world settings which will allow the materials (shaders) to interact properly. Neither of these renderers by Chaos Group have an "automatic exposure" setting or at least they didn't up until a year ago when I stopped using them. I've only encountered this feature in TwimMotion and Chief. Using automatic exposure would negate the process I describe above as you would never know if the scene was calibrated correctly. That said, I'm not sure if Chief's Sun and default setting of 7000 under "Daytime Backdrop Intensity" represent any real world values. I would imagine they do but have no idea what they are.

I don't use automatic exposure as it is impossible to balance the light correctly. Lumens are now used to specify the total light output of a fixture regardless of the size or shape of the lens. Unlike watts that is size dependent. If the area light is indicated to be 800 lumens that's how much light it should emit. That's not what I'm seeing in Chief when I use an area light on its own. I am attempting to get clarification from Trent on why you can use the area lights in conjunction with a spot or point and how that affects the illumination. I am not worried about the IES data of the fixture at this time although that would be nice - only the total light output. I've been using Corona Renderer for over 15 years, and although Chief does not have many of the shader features such as SSS, I am getting very similar results with it without all the trouble of exporting to another software. It's very close to a one software solution which saves me lots of time.

Thanks for the reply. I never use automatic exposure. The lumens do not seem correct to me when using an area light on its own.

@Chief_TrentThanks Trent. It's good to know that turning off the sun (which I do often) requires that you increase the Nighttime Backdrop Intensity. Maybe you can answer something for me. Why do we have the ability to use both area lights and the point or spot light when it is already used in a fixture. For example, I have created my own downlights (celling LED's) which have a spot light aimed at the floor. In addition to this, the lens on this light has an emissive material applied. I realize that the most accurate way is to use the area light from the lens solely (without the spot) or at least that is how it's done in other software I use. However, when working with the area light alone, I must turn up the intensity of the lumens to an unreasonable amount to get the output I would expect to see (such as a 1,000 lumen ceiling light). The area light alone needs to be set to 10k or more. When the spot light and the area light are used together, the lumens seem to be more accurate. What is the most accurate way in Chief to represent a 800 to 1,000 ceiling downlight. In combination or area light alone? Also, how does ticking "Apply Emissive and Color from Light(s)" factor in? Does this retain true area lighting with the spot light settings driving the output? Or am I even getting an area light when I do this? This is not as straight forward as it is in other PBR software. All I know is that when I use area lights alone, I am not getting the expected lumen output which leads me to believe I am doing something wrong.

Thanks Renee. I see that now.

Is there a way to increase the brightness of an HDRI used as a backdrop? Thanks, Kevin

Thanks Rob!