Lighting for flat bottomed object super dark

[itman496]

Hello, rendering a ship and I can't seem to get the underside to work properly.  I'll admit I'm a bit of a newbie with keyshot.

I even tried adding a panel under the model and making it emissive to light up the bottom, but the perfectly perpendicular to the ground bits still show up weird! (no detail, flat color)

refer to this series of images.  The first one is no shadows, so you can see what is supposed to be there.  The first one is no extra light, the second is with the light panel.  See how the flat bottom still doesn't render properly?  I'm confused, I have a panel light pointed right at it..  I assume it is a setting that I'm missing.  Thanks for the great work on this program! It's much better then simlab..

[richardfunnell]

Do you still see the same result when you turn off ground shadows? Project > Environment > Ground > Ground Shadows.
Feel free to send us the file using https://keyshot.wetransfer.com if you'd like us to take a look at the scene, it won't be publicly shared.

[itman496]

ground shadows does make it stop, as it does in the first embedded image, but it also gets rid of all the nice shading like in the second image.  Do you want the sketchup file to see if its an importing problem?  There is nothing happening once it imports, I'm rendering straight off of all default textures and settings of the import.

[Will Gibbons]

Also, what's the effect of moving the object up and turning on ground reflections. Also, making some planes to introduce an indirect light source may help?

[richardfunnell]

Will's suggestions for moving the object up will definitely help, but would you be able to share the SketchUp file as well to see the issue in detail?

My apologies for the delayed response, I've been traveling for the past 2 weeks. You can send the file via https://keyshot.wetransfer.com

[edwardo]

Forgive me if this is overly simple... but would just tilting the HDR (if you have the HDR editor) help at all? The bottom/floor of hdr's are often solid, flat colour and it is lighting the underside of your model perfectly perpendicularly. Similarly, you could just add a few lights/darker spots to the floor of your HDR dome.

E

[itman496]

I've tried rotating and tilting the hdri and also adding some planes at angles underneith.  It appears that keyshot absolutely refuses to light anything that is parallel to the ground, which is strange.

It lights every other underside surface perfectly, too! It's very confusing.  Everything except the parallel is great.  It abruptly goes black too, which obviously the lighting wouldn't really do.  And I've had literal planes of light aimed at the bottom of the craft, and it's still dark!

Here is the file, please let me know if you have any luck!

https://dl.dropboxusercontent.com/u/4963246/mars%20racer/testmodellighting.skp

[itman496]

anyone have any luck?

[KeyShot]

To illuminate the bottom of objects you can use the new interior lighting mode in KeyShot 6 which considers lighting from the full environment. For products KeyShot assumes the product is placed on the ground and only the lighting from above is used. This is why the bottom is darker.

[theAVator]

I can't see the actual images posted (stupid IT security policies), so I am starting blind. But I'm just wondering if everything in the model is above the ground plane when it's imported into KeyShot? I know when our engineers do some of our models they come in in all sorts of different positions and on different axis'.  Right now I have a couple models that are like 50% above and 50% below the ground plane, which messes with the shadows and some of the lighting and etc.

Just throwing an idea out there....