Simple questions: animation rendering

[skogzort]

Hello all,
I have read through the tutorial and some other posts on this topic, but I still have a couple simple questions. The tutorial uses the strategy of:

1) Light Cache for Primary and Secondary bounces then
2) Irradiance Map for Primary (with the saved LC being used for Secondary Bounce)
3) When the IR map has been saved, you no longer need to use the Light Cache for Secondary (because it has been worked into the Irradiance Map)

First question:
What is the advantage to using the LC then the IM, as opposed to just using the IM for both Primary and Secondary bounces from the start?

Second question:
The LC has a check box to “store direct light” and the lights themselves have a checkbox to “store with irradiance map” – If both are checked and you use the strategy in the tutorial, what overrides? In other words which method actually stores the direct light: IM or LC? Which one does a better job with rendering the direct light?

Thanks much for your help

[vlado]

Re: Simple questions: animation rendering

First question:
What is the advantage to using the LC then the IM, as opposed to just using the IM for both Primary and Secondary bounces from the start?

As far as the final result goes, there is no difference. In the tutorial, we used this sequence of steps for illustrative purposes.

Second question:
The LC has a check box to “store direct light” and the lights themselves have a checkbox to “store with irradiance map” – If both are checked and you use the strategy in the tutorial, what overrides? In other words which method actually stores the direct light: IM or LC? Which one does a better job with rendering the direct light?

They are different options, so one does not override the other. Storing the direct illumination typically lowers the quality of the final result but improves noise/render times. The defaults are quite good for a start.

Best regards,
Vlado