Light Cache vs. actual render

[peakyfreak80]

I'm working on an interior scene and having some problems with the lighting. I've attached two images. The first is essentially a screen-cap of the lightcache right before it renders. The second is after it renders. I really like the lighting in the pre-render, but whenever it renders, it becomes very dark and I lose a lot of the detail that I need.

I can obviously pump up the lights, but for some reason I always thought the pre-render looked pretty close to the actual render.

Can anybody straighten me out on this situation?

Thanks

peakyfreak

[rmejia]

What are your GI settings, primary and secondary bounces ? Do you have the "Store with irradiance map" option selected in the lights?

[vlado]

Have you accidentally turned on the "Show GI only" option in the global switches section of V-Ray?

Best regards,
Vlado

[peakyfreak80]

I have light planes at the windows to control color and intensity and they do have "Store With Irradiance Map" checked. Settings are:

Primary: Irradiance Map -4, -2
Nothing else fancy in these settings
Secondary: Lightcache
Samples: 1000
Screen: .02
Store Direct Light
Prefilter: 10
Filter: Nearest

I checked to see if I had the GI only checkbox on, and I did not. But, now I know a new checkbox. Never saw that one before!

I'll keep on tweaking things to see what I can come up with. I turned on the RawGI element and turned off filtering (in lightcache) and it looks like I just wasn't getting enough lighting back there. That shows a much closer representation of my final rendering than the pure lightcache screen cap did.

More to come...thanks!

peakyfreak

[vlado]

What does the light cache itself look like (if you use it as a primary engine too)?

Best regards,
Vlado

[peakyfreak80]

Both of those images were from the initial lightcache-lightcache test. I wasn't happy with my results from my typical settings so I decided to start to pick the lighting apart, and I started with the straight lightcache pass.

[vlado]

Well, if the lights have the "Store with irradiance map" option, they will render black if you don't use the irradiance map.

Best regards,
Vlado

[peakyfreak80]

I think what happened was A: with the lights set as "Include with Irradiance Map" it was causing some issues, but B: when I didn't filter the samples, i could see that there just wasn't enough light or samples getting back there, so when Vray filtered them, it just ended up smoothing right over the brighter spots.

Is there an easy way to send this over to the Images Upload forum, or should I just start a new thread over there? I've got some images ready I'd like to be critiqued.

Thanks guys!

peakyfreak

[vlado]

Best to start a new topic, I guess.

Best regards,
Vlado