Create model with Rhino for Keyshot

[Gabik87]

Dear All,
Every time, I ask myself if it is appropriate to model in Rhino in mm or in cm.
Both for the heaviness of the file in keyshot (with relative increase of render time) and for a correct correspondence with the HDRì.
Also for the size of the textures.

In your opinion, in Rhino what should be set as a unit of measure?

Thanks in advance for your answers.

[RRIS]

Doesn't really matter, depends on the accuracy you want to work in.
I usually work either in mm's for anything up to car-size.

As long as you use the same units in Keyshot (edit > set scene units) there's no problem.

[Gabik87]

Thanks RRIS.
So I have to check this setting on Keyshot.
So if I have mm in Rhino and mm in Keyshot I have no problems. (because sometime, I don't understand increase time of render).

for example, I've a 3d urban furniture, so sometimes they are products with a height of 1000mm, so I don't know if it's better to leave them in real scale or reduce the scale to make the render.
This is another dilemma for me.

But do the HDRI images automatically adapt to the unit of measure set on Keyshot, or do they have a setting of their own?


Thanks again

Doesn't really matter, depends on the accuracy you want to work in.
I usually work either in mm's for anything up to car-size.

As long as you use the same units in Keyshot (edit > set scene units) there's no problem.

[RRIS]

Check the size of the environment in the environment tab. If your object is 1000mm, then there's no reason to have a 100.000mm (for example) sized environment.
Same with floor size. Make it as large as you need, not as large as you can...

[mattjgerard]

And number of polygons won't affect the render time that much unless you have some geometry based material interactions going on, it will just increase the time it will take to package and transfer the file if you are network rendering.

I find that my cad files come in at any ungodly size they feel like, so I am constantly calibrating and resetting the units in my scenes. I have objects that are in real life 2-5 mm across that come in as thousands of MM, and if I don't scale them properly light settings, transmission settings, etc are all waaaaay off. Scene units are much more important these days than they used to be.

[RRIS]

... if I don't scale them properly light settings, transmission settings, etc are all waaaaay off.

Ah yes, this is very true. Scale should be 1:1 as much as possible, but in which units is only important for how many decimals of accuracy you need.

[Gabik87]

I will show you just one example.
you don't watch the preview, because I omitted some objects in the scene.

For example, there are objects that are 1000mm high in the scene and others even 500mm.
In this case how do I size the HDRI of the scene? Is this proportion correct?
Because beyond the textures I don't want to ruin the reality of my render, with wrong settings in the scene.

Thank so much for your interest about my problem

And number of polygons won't affect the render time that much unless you have some geometry based material interactions going on, it will just increase the time it will take to package and transfer the file if you are network rendering.

I find that my cad files come in at any ungodly size they feel like, so I am constantly calibrating and resetting the units in my scenes. I have objects that are in real life 2-5 mm across that come in as thousands of MM, and if I don't scale them properly light settings, transmission settings, etc are all waaaaay off. Scene units are much more important these days than they used to be.

[RRIS]

12000mm is quite large for the type of object you're showing, so feel free to make it smaller. 3000mm probably works fine as well.

I'm not sure, but do you want to use the environment also as a background in your renders? Because then environment size becomes more important. However, I don't think the environment you're using is high-res enough for this purpose. So, you're probably better off using a backplate and match the camera angle to your backplate as much as possible.

If you don't feel like using backplates, make sure you use high resolution environments, something like 8K or even 16K (but your computer may hate you for it). Try https://hdrihaven.com/. Some of the HDR's there also have nice backplates.

[Gabik87]

no no, it was just to show the proportion of my HDRI.
Another thing, how do I get (for more quality and truth of my image), a reflection of my backplate in the surface of my object?

Thanks

12000mm is quite large for the type of object you're showing, so feel free to make it smaller. 3000mm probably works fine as well.

I'm not sure, but do you want to use the environment also as a background in your renders? Because then environment size becomes more important. However, I don't think the environment you're using is high-res enough for this purpose. So, you're probably better off using a backplate and match the camera angle to your backplate as much as possible.

If you don't feel like using backplates, make sure you use high resolution environments, something like 8K or even 16K (but your computer may hate you for it). Try https://hdrihaven.com/. Some of the HDR's there also have nice backplates.

[RRIS]

Backplates are only there to make compositing your rendering in a background easier, they won't reflect in objects. So always make sure you have matching backplates with your hdr (this hdr for example: https://hdrihaven.com/hdri/?h=umhlanga_sunrise ).