(Iray) Lighting Collection Prop Set too dark?

Evenios

Ok maybe its just me ...but when i load up the props with the Lighting Collection Prop Set thats supposed to work with iray all of the objects are way too dark. and i make sure i use the iray matierals. that and its a tad misleading and a bit of a let down that the torch/flashlight is not a charecter prop.  but even the flashlight is too dark.  in a small hallway i ppoint it towards the door and barly any light at all. im using default  settings for scene lighting only

anyone else with this issue?  i found adjusting the exposure value /iso helps. perhaps thats what needed? :-p

dunno still seems too dark to me...........

SpottedKitty

Evenios said:

i found adjusting the exposure value /iso helps. perhaps thats what needed? :-p

Yes, that's the tonemapping settings — and the problem is that they're optimised for the brightness of a clear sunny day (as in the default environment light). Think of them as the actual physical camera settings that they are: use a slower shutter speed, a wider aperture f/stop, and a higher ISO value, to make up for the D|S camera not having a flash.

Evenios

thanks kitty!  yeah it helps a bit. ;-)

(Update): yay! i made a nice photo with it!  now i think i am in love with candleabras!

suggestion:  moar candlelabras!

 

Tobor

Just remember that Iray is afraid of the dark. Without enough photons, it has much less to work with when rendering a scene. It counts on re-tracing from light source to the camera multiple times in order to know that its math calculations are providing accurate results -- that's convergence. Without enough light in the scene, it can take a month of Sundays for the thing to render. In essense, Iray keeps wondering if it's on the right track.

So while you can adjust the tone mapping settings, that doesn't increase the amount of light in the scene. In the real world, a room can be lit with a single lamp. We're only simulating the real world here, and sometimes it's necessary to use some movie-making trickery to balance our needs of enough light to make an image on Iray "film," and the right balance of light for the scene.

One thing you can do is add some ambient light by using an HDR image of a modestly-lit interior. You can adjust the intensity of the environment light to set the tone. You can then add the "prop" lights that appear on camera.  They only have to look like they are providing the room light. Adjust them so they have the right balance with the environment. Their default settings were someone else's idea. You're the movie director here; set them the way you need.

When your lighting is set, you can adjust the Iray camera via tone mapping. Thanks to having more light Iray will now render the scene faster. Use the tone mapping settings to fine-tune the mood.

Richard Haseltine

I have seen Tone Maping Settings affect time to converge, though I was using fairly extreme values to test.

Tobor

I'd assume some influence on tone mapping settings and render times in order to support certain features -- such as camera/object blur, not yet implemented in D|S -- but I'm not certain that is truly intentional, as it is biased. Camera settings don't change the amount of avalable light. It would also have marginal effect when using canvases, which work best with tone mapping off.

I bring this up each time because in the real world, you'd certainly adjust the camera for proper exosure. But Iray has a limitation related to its minimum light levels, I suppose not unlike digital camers that need certain lux to overcome the noise floor of the sensor. At some point, there are no camera settings that will correct for it. My points related to this is to suggest an increase of light to overcome Iray's limitation, so that the artistic intent is easier to achieve.

 

Evenios

in that one picture i posted the render time to get it to that point wanst terrible considering some other scenes i did that were brighter. so i guess it goes with playing with the settings. but thanks :-).