Multiplane Cyclorama background renders darker than the ground
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Okay, I've been occasionally using the various Multiplane Cyclorama scenes in renders... and right now, I'm trying to do one with the beach theme. Trouble is, the curved background part of it keeps coming out noticibly darker than the rest of it all, which kinda spoils the effect. This is in iray. I've tried plopping various sorts of lights (pointlight, distant lights, etc) pointing at that section then upped the lums to the stratosphere, but it doesn't seem to make any real difference. Is there a quick, simple way to make that part of the scene be lit to the same extent as the ground and the little sand-hills? I think I once got it the way I wanted with a bunch of ghostlights, but it was a tedious nuisance. I just want to slam-bang the cyclorama in place, plop one or more characters in for their portrait, and hit Render. 0o
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Wow, this one has been in here a long time and no one said anything. Sorry, I guess I wasn't clear enough about what help I was trying to obtain with the above post:
What is the best, easiest, and consistently reliable way to make one of the Multiplane Cyclorama-based backdrop scenes be lit up evenly when using the iRay render engine? I've been assuming there's a simple, easy way, but I've not found it yet.
Make sure the sun is shining on the front of the Cyclorama and not behind it which will put it in shade.
What I do is
By "Apply the default Iray shader," you mean apply !Iray Uber Base, right?
Well, tried it on a render before going to bed. Loaded the scene with one of the Multiplane Cyclorama sets in it, selected the Cyclorama prop, in Surfaces selected (hilighted) all the surfaces, applied !iray uber base, went through each surface, found that the glossy color was already set to black on all of them, found the base color texture map on the first surface, set the luinance to point to the same image, set the luminance to 150 (it was set to 10), went on through the rest of the surfaces and found none of them had an image set to any texture on those, but then all the extra panes of the particular Cyclorama had nothing on them in scene anyway, so left those surfaces alone. Did a test render and... no obvious visible change took place in the result, the backdrop part of the Cyclorama was still coming out dimmer than the floor part of it, so I retried it with Luminance set to 300 on the first surface, and still nothing visible seemed to have changed.
Am I missing something?
Just in case, you do have the ground turned off on your HDRI and the ground set to manual?
So far as I know, I'm using whatever the default lighting is in DS, I haven't loaded any HDRIs beyond the DTHDR-RuinsB-500.hdr one that arrives by default when you make a fresh scene. My scene SHOULD be in whatever the settngs are that one gets upon firing up Daz, loading a set and a couple characters, some basic props (none of which are emissive), and then simply placing out a camera. I don't even have any lights placed out. In fact, the camera itself I set Headlamp Mode to Off. There is no rotation set to the Cyclorama, either... that is, I haven't rotated it around a different direction or anything. Anyway, wouldn't Draw Dome being OFF ignore whatever the draw ground settings are?
Nope, the ground will still provide shadows even with the dome off. I will try a render and see if I can replicate this.
Okay, I dug out the Beach version of the Multi Plane Cyclorama (circa May 10th 2002 18 years old!), I did a quick and dirty iRay conversion, I applied a lovely beach HDRI but hid the dome since the default is moe like midnight with a spotlight), I turned off the ground in the Render Tab;I suspect that dark thing you are seeing is the shadow of the bottom o the Cyclorama on the invisible ground, and I used the Rim Light Rig Iray since there should be bright diffuse light and i could scale it to cover the width of the Cyclorama. And it is ugly... The resolution is poor, the seams show, the billboard dunes don't match and look flat, and I would say don't put too much effort into an iray conversion of a 18 year old product.
Here is the attempt:
And here is an image I did using a nice simple HDRI so you can see why people don't use such things like the cyclorama in iray.
Well, my problem is that the ground is lit up, and the background part is dimmer. In my case, though, I'm using one of the forrest cycloramas.
The attached images all use the Cyclorama in Iray.
A short animation.
https://www.youtube.com/watch?v=J_rei8D0lIc&feature=youtu.be
Well, I tried turning Draw Ground to off and rerendered my scene. It made zero visible diffrerence. Mind you, this time I didn't go through and set emissives the way nemesis10 said. (I didn't try saving it out earlier with the changes made, and was too lazy to do all that this time, but I didn't see any real difference earlier when I tried those settings, either.) Here is the scene with all the characters and props removed. It is now literally just the cyclorama and the camera, and nothing else. Notice how the grassy floor is noticibly lighter than the background.
I believe the particular cyclorama is something with Eden in the name.
But yeah, I was having a similar problem with that beach background, and a sandy dunes background: The floor of the scene was somewhat lit, the vertical background was noticibly dimmer. This is also descernable in that beach scene in Fishtale's post above: the surf should be a lot more lit up than that.
I loaded the beach cyclorama to have a look The image looks like a very badly scanned photograph which has a colour cast and, because it looks like sunset, is very dark on the left. It also looks dark and the ground light because of the way the Cyclorama loads the image. I took the image into Photoshop and ran some filters on it which made it better. I also lowered the rock planes into the sand to hind them and changed the diffuse base colour from white (255) to a greyer colour (225) which got them closer to the sand colour of the main image. I also put the Diffuse image into the Dome and added a Distant Light from the top right.
Looks a lot better. This is in Iray.
Eagle Beach.
2020-04-02 20:35:17.483 Total Rendering Time: 4 minutes 38.85 seconds
Click on image for full size.
Well, I did a bit more poking around through some of my other renders I had done with one or the other of these Multiplane Cyclorama stage sets, trying to find one or more scene where I'd solved the problem with carefully placed ghost-lights or something... so I could apply that to the current scene, and I discovered something interesting. Seems one scene I had done with a multiplane cyclorama DID come out evenly lit, and it turns out I hadn't added any lights to it, ghostlight or otherwise, and I'd also had the headlamp on the camera set to Off, so literally the only light that was in play was the default, overall, we're-not-somewhere-inside light. BUT, for some reason I'd also set the cyclorama to a Yrotation of 30, and had also set the camera to a Yrotation of 30 and moved it sideways accordingly... probably because it was simpler to move the background and the camera than it was to rotate the character and all the props in the scene. And in the render I had done with this scene, the background was more similarly lit to the ground.
At that point, it dawned on me what was going on here.
In my current scene, both the cyclorama and the camera are at a Yrotation of 0 or so. And the vertical part of the cyclorama is coming out dimmer. The vertical backdrop section of the cyclorama is a curved surface, and presumably the generated-by-DS, default "outside" light-source, is coming in from the side!
So, I tried an experiment, and rotated the cyclorama in my current scene to a Yrotation 25 or so, and then shifted the cyclorama to an Xtransfer of 200 so that the one edge of the background didn't fall outside the view in my camera... and lo and behold, the background section was no longer quite so dim in the scene, and came much closer to the lit-up-ness of the ground.
I went back to my scene with JUST the multiplane cyclorama and the camera, and then set the cyclorama to a Yrotation of 30, and set the camera to a Yrotation of 30, and rendered it. (I can't show you my other scene, since it is rather NSFW)
Anyway, it seems the curvedness of the back section of the multiplane cyclorama is working against it... because Iray is treating it as a wall that blocks some of the light from coming through and fully lighting up the inside back of the thing. 0o
Hmmmmm!
https://www.daz3d.com/forums/discussion/comment/5483781/#Comment_5483781
Hmmmmm....
Yeah, saw that comment... but since it was a mite underexplained, i.e. didn't mention that the loaded-as-default lighting is OUT of allignment with the Multiplane Cyclorama, I read that comment as "Make sure any third-party lighting isn't out of alignment with this prop." It literally never occurred to me that the loaded-as-default one WOULD be out of allignment with this prop, since usually you'd figure the light is coming in from somewhere behind where a freshly created camera is pointed by default, not off somewhere perpindicular to it.
So, is there a chart somewhere showing how the default outside-world-lighting is alligned "geographically" in scene? I.e. is it 90 degrees off from a yrot 0 camera rotation? Is it 45 degrees off from that?
The default loads with the camera facing the wrong way (as far as I am concerned) so the sun is always on the wrong side of anything loaded at the default 0,0,0. I turn the Dome 180º so that the sun is rising in the east, the left of the frame, and not the west. The default load is for Midday so I have that set for 14:30 at my Lat/Long so I have a fair idea where the sun should be in the sky and also gives some nice shadows which helps highlight any bumps and lumps
When I load a figure I use the 'Y' setting to turn it so the sun is shining on it and turn the camera to face it and then use the sliders to then place it in the scene. When using a Map in the Environment Pane I just turn it to get the light coming from the direction I want it and sometimes use a Distant Light as a fill light if I feel there isn't enough ambient light in the shadows.