The point of HDRI's

For a while now I have been kind of familiar with HDRI’s and using them for lighting a scene, I sometimes use one to get a better sense of what my model and materials look like. But I don’t understand what the purpose is for production use, why do I need it to achieve physically accurate lighting, can’t I just achieve the same quality through materials and or built in lighting objects? Isn’t the point of CGI to simulate reality and or stylized look? For the former wouldn’t using reality to simulate reality be counterproductive?

You could ask the same question about photo textures. It really depends on what you want to achieve. If you want to aim for realism and/or want to add a bit of subtle variation to your lighting setup, that’s when you would use an hdri.

There are other cases as well, for example, imagine you’re trying to blend a cg object with a photo/video. In that case you would want the most realistic lighting possible to be cast onto your model.

Or, say you’ve created a model that incorporates highly reflective materials. In that case, unless you want to unnecessarily model things that are behind your camera, you would use an hdri.

And no, using reality to simulate reality is not counter productive. Using an hdri is simply a much easier way to add a nice bit of detail to a model. Just my two cents.

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Same reason we use normal or bump maps. In the end it is all about working efficiently, saving time, money and freeing up processing power.

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For movie production, it’s about capturing the real lighting conditions and environment on set. Any CG you put in there has to match the live footage. Since conditions can be really complex, if you just grab the HDR you’re pretty much all set as far as matching CG into the scene. Try doing this with manual lighting setups.
Then there are the hobbyists, like probably most of us. HDR gives access to complex lighting and reflection scenarios without any effort. But also with out any control. I think it is perfectly valid to check models in, as well as present models in. As for “beautiful” lighting in certain types of artistic scenes (not models), nothing beats manual lighting imo. Same as a real studio photographer, directing light is of incredible importance to make “beautiful” shots. Even set photographers will crave for lighting control.
HDR is more realistic for sure. But it’s way more costly (for interiors), and surely don’t create the best lighted scenes. Most/many interior photographers also will rely on lighting or at least photoshopping to get the most out of shots - not just selecting the best photo of the batch and tweak the curves a bit.
HDR is more realistic. But not the best. Think of it as a tool in the toolbox, but don’t let it become the only tool. In my opinion.

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