New here, just starting to use Corona.
Your gonna laugh, but…when do you stop the render…rendering?
Been using Vray for years, and when it’s done it’s done.
Also the Basic materials I have been using them, is there a set people use in general.
So enlighten me please.
I thank you.
Phil
HI Philippe.
This is a different type of render engine, the render can last forever if you want, think about it like the shutter speed of a camera, the longer it is exposed, the most light enters in the sensor.
This is somewhat similar, you may define a fixed render time, let’s say 10 minutes, and you will be sure that the render process will be finished in 10 minuts, but the image could be still very noisy, the other way to stop the render is to define a sampling level, for example 100 samples, this way you will ensure a minimum sampling level (a defined noise level), and this is the mode you should use for animations to avoide different noise levels between frames, now, how do you define the sampling level you want? you can leave the render for an undefined time and check the level from time to time, one you see you are in the level you want you know this is the stop level you should use, also you can think in time, try limiting the render in time, let’s say 15 minutes, now if you are happy with that result check the level reached and use that, if you are not happy, repeat the proccess but increasing the time.
BTW sampling levels are passes in corona.
Hope this helps you a bit.
Cheers!
Juang3D
Thank you that’s very helpful.
I have used Vray RT a lot on the past, so I understand the principles of the system.
Bu thank you I do appreciate the time and effort you took to respond.
On-wards and upwards as they say, “The worlds your Corona”
Phil
How come nobody uses there real name here ?
Actually this comparison may be misleading. The image in Corona won’t get any brighter as the rendering continues. 
You can read some articles on this topic here:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000517898
https://coronarenderer.freshdesk.com/support/solutions/articles/5000516260
That is true, I was just trying to imply that the longer you leave the render going, the more developed will be your picture, and the shutter it’s a good explanation, but I agree that I should have explained that in this case the “shutter” I’m talking about just affects noise, and the real exposure shutter is a separate setting in the corona camera mod, the physical camera or corona render settings 
But I found that this explanation makes it easy for people to understand how the engine works.
Cheers.
I think that comparison can be correct as long as you take auto ISO into account :]