4.20 update interiors now super dark for anyone else?
sunnyjei
Posts: 502
Was excited to check out the new update and unfortunately discovered previously well lit interior scenes are now all incredibly near black dark. All three of the hobbit style home sets (https://www.daz3d.com/rog-fantasy-home--hallway ,etc) used to look like their day time promo pages. Has anyone else found a work around or had issues too?
--Edit-
I don't think it is ghost lights/mesh lights (?) as changing the the tone mapping and environment settings still leaves the scene dark unless I crank it up considerably ...going to try other outdoor scenes too next
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It seems like mesh lights aren't working in 4.20 any longer, I used the Ghost Light Kits from Kindred Arts in almost all my renders, and they don't work any longer and have also disappeared from the shop.
See this thread about Kindred Arts lights sets: https://www.daz3d.com/forums/discussion/551301/ghost-lights-what-s-happening-and-what-s-next#latest
Explanation: https://www.daz3d.com/forums/discussion/comment/7329401/#Comment_7329401
A workaround mesh light fix: https://www.daz3d.com/forums/discussion/548061/iray-ghost-light-fix-dse-for-daz-studio-4-20-o-later#latest
There's a thread from KA from a couple hours ago about ghost lights:
Ghost Lights - What's happening, and what's next. - Daz 3D Forums
*Edit* sorry about the repost of the KA thread, for some reason none of the other posts showed on my computer until after I hit the submit comment button.
Thanks- I don't think the set is using any ghost lights? Even changing the tonemapping settings and environment intensity still leaves the scene really dark...
Still need to see what this is about - haven't been able to figure it out in 4.20 yet?
Hmm, playing around more and it only seems to be some indoor sets as all the outdoor sets are fine. I didn't think there were mesh lights or ghost lights in the affected sets but turning the Film iso up to 1000+ gave very warm mid day indoor lighting effects- unfortunately though it also seemed to make my graphics card work a lot harder (?) I was hitting temps of 80C and I don't normally get that high with the iray preview
Hence why I save the few prior versions of DS
Have any of you tried lowering the shutter speed and f/stop on the tone mapping pane and raising the Film ISO?
Try setting the f/stop between 1 and 1.7 and the Shutter Speed down to something between 10-20.
Raise the Film ISO up to around 400.
See if that helps.
If it does, then adjust the settings to what looks good for your indoor scene.
Just adjusting the tone mapping has two major snags.
1) The render time will be very slow, as despite the image being brighter, it will still take a long time to clean up the noise in the darker areas.
2) The image will look very different to what is was before, since all the tone mapping does is raise the brightness of the whole image, rather than just those parts that are now darkened by the misfunctioning ghost lights.
A better solution is to locate which mesh lights are giving off a lot less light than before, and then go into the surface settings, locate the luminence, and start adding a lot of zeros (7 if this is a default ghost light)
Unless you turn it off, you are using the Tone mapping in every scene no matter what settings you use.
In my opinion, if you are going to use it, may as well learn to use the settings so it can a positive effect on your renders.
One can always turn it off and light the scene manually.That's alot of work though.I prefer to use the tone mapper instead :)
...same here.
Looks like this will be a miss for me as I find mesh lights one of the more useful features of Iray. One of the tedious tasks in 3DL was having to put point lights next to light bulbs, lamps, flames etc to fake that they were light sources, and creating a beam like from an electric torch or vehicle headlamps was a real pain.
To be honesty, this is somethng that ive experienced for years in studio. Sometiems I can tweak the drawstle menu and it offers sme relief. Or I disassmelb ehte room, take a couple walls and the roof off and fiddle with lights myself. Its always been an issue for me.
I have been rendering in The Streets of Morocco and used SY's Invisilights for the first time to test 4.20 on a MacBook Pro M1 and have been pleased with the ease and results so far. I am a big fan of KA's Mesh Lights and have kept one version of Beta 4.15 on a Windows 10 installed just so I could still use them.
I'm not sure why anyone is saying mesh lights don't work anymore.
They most certainly do.
I can add more of them to this scene, out of view of the camera, to light the whole subterranean crypt with them.
edit:This scene is all default.No Tone Mapping changes, I did change to kcd/m2 because cd/m2 is just to low for default settings to emitt enough light.
...what's the luminosity value set at?
Could you do a test set to equivalent luminosity using the Watts scale?
Part of the reason I rarely usephotometric lights as I often have to set them at ridiculous value levels that have no basis in "real world" lighting.
I left everything at default and just switched the luminance units to kcdm/2 and turned "2 Sided Light" off and that was it.
I created a 1M primitive plane.Changed the Emission Color to white(255 255 255), switched the luminance units. Raised it off the floor to Y=300 and then tilted it a bit X Rotate =-130
Then loaded "Cista Sanctus Legacy" so I'd have a nice dark damp crypt to work in.
https://www.daz3d.com/cista-sanctus
Then hit the Iray preview render button.Worked just fine for me :)
I've actually been playing with it for hours now. Got inspired to make a few Tombraider/crypt researcher type renders.
I think what everyone is talking about is that ghost lights don't work like they did before. Ghost lights are mesh lights, so they are being called mesh lights for short?? All mesh lights with opacity at 1 still work the same. Ghost lights were an exploit of a bug in Iray that allowed the opacity of a mesh to be dropped down to 0.01 (or more) and be virtually transparent in the render yet cast light as if it wasn't transparent. Nvidia "fixed" the bug and now to get them to work, you need to increase the lumens to very ridiculous levels to get the nearly transparent object to cast a light. Just guessing here, but they might had to fix the bug to get another feature or a new feature working properly (possibly for volumes to work as desired).
I seldom used this work around because it also meant that the lights didn't reflect (i.e. no glossy/specular effect on surfaces). They also tend to give an unnatural look to images (just my experience/opinion here), and cause a bit of weirdness in the image behind them. So it's not a huge issue for me. But for many people they have been a big part of their workflow, and are used in scenes that are re-used for subsequent renders. That's what I think most of the complaints are about. I've been using DS 4.20 most of the day, and haven't had one issue with normal mesh lights.
But I am experiencing random issues with objects no clearing from the render when turned off, requiring either reloading the scene, or deleting and re-loading the object
Yeah, I kind of assumed that "mesh light" was being used as a generic term to cover any light made from a primitive with the emmision turned on.Hence my post.
I was trying to point out that mesh lights do work.
I really don't think Nvidia is going to roll back the fixes for this bug.
If "ghost lights" are to be a feature in Studio, Daz will have to develop an implimentation for them on their own.
Agreed, I doubt they will get "un-fixed" too. Especially since they didn't follow proper light physics. Though if other segments of Nvidias user base were using them extensively as well, we could possibly see a special mesh light type in the future. Typically bugs like this one don't get fixed unless there is a real reason to fix them (i.e. they are causing unresolvable problems with other features not working as desired, or they need to be fixed to enable a new feature).
I was actually very worried about the same thing because, for the most part, I light everything with emissive planes. I appreciate you showing that that is still an option. I now feel comfortable updating to 4.20.
...I just ran a few tests with Cista Sanctus (I don't have the Iray textures so the water turns up "meh" but that's not really important for this). However I adjusted the tone mapping to simulate as close to what the natural eye sees. I used a shutter speed value of 1/1 as the eyes and pupils are usually always open, fstop set to 2.8 and ISO of 800 both which simulate the pupil dilated for low light conditions. This yields an "Exposure Rate" (if that can be applicable to the human eye) of 5.97 I also set Crush Blacks to 0 as that is a digital photographic technique used to remove all light from the darkest areas of an digital image often use to give a the subject more "pop" against the background. it is not something the eyes naturally do.
Instead of a plane, I loaded a lamp prop with an actual light bulb mesh in the scene, inverted it, and set its Y value to where the bulb was at about 2.5m above the floor ( the average height for a ceiling light). For the luminosity I used the equivalent of a 60 watt incandescent bulb which produces 800 lumens I set the efficacy of lm/W at 13.334 which is the efficacy for a 60W incandescent bulb. Using the same tone mapping settings above and the set looked as if it was indeed illuminated by a 60 watt bulb. at 2.5 meters from the floor. I next used the settings for a 12 watt LED (equivalent light of a 60 W incandescent) that has an efficacy of 66.667. I plugged in those numbers in and received the same result. Finally I set the luminance units to Lumens and ran a third test. which again yielded the same results.
So a little research goes a long way to avoid trial and error as well as arbitrarily pumping up values to ludicrous levels (like 1.5 million candela) to get an adequately lit interior scene. unfortunately a camera has certain limitations.
When I did photography (film based) I used a number of tricks for available light photography (without flash) and often found the film speed to be the most limiting factor as I could set the f stop to the maximum aperture, and for extremely low lit settings slow the shutter speed down to 1/2 requiring a tripod and cable shutter release so as not to vibrate the camera). For such photography I used ISO 400 Ektacrhome transparency film which even when pushed to 600 ISO remained fairly grain free.
Oh and this was done in 4.16.40 haven' t updated to 4.20 yet.
Attachments:
#1. Test with 60 W incandescent bulb
#2. Test with 12 W (60 eff. W) LED bulb
#3. Test with bulb using 800 lumen setting
Using the ROG Fantasy Home as an example- because the promos looked pretty much the same in Daz for me so it is an easy comparison of what it should look like versus what it looks like in 4.20 (no shade to the creator of the set it is beautiful and was lit beautifully pre-update!).
Promo/Pre 4.20
And what I'm getting without tone mapping tweaks and with tweaks. Just in the preview my gpu is going from around 41-44C (without tweaks) to 65-80C (with tweaks) and with tweaks the preview time has increased considerably and still not clear.
(No tweaks)
With tone mapping tweaks mentioned above
DAZ have already implemented their own ghost lights. They were introduced in 4.16 and are also present in 4.20. They are mentioned as part of the 4.20 features here: https://blog.daz3d.com/daz-studio-4-20-volumetric-clouds-smoke-and-fire-effects/
They will not be identical to existing ghost lights, but they do have some advantages from the old style, in particular they can emit light, remain invisible to the camera, but still cause reflections on their targets. This is undesirable for things like mirrors and windows, but very desirable for things like skin, or shinny objects, that otherwise look flat and dull without any specularity. The ability to make other objects reflect light can be toggled on and off I believe.
Yeah, I posted a mini "how-to" on the beta thread along with renders when that first became available explaining how to set them up.
Here's where it starts
https://www.daz3d.com/forums/discussion/comment/7175736/#Comment_7175736
I just brought up on the ROG sets and tried a render, and I'm getting the same issue, Sunnyjei. I don't have an answer. I hope the artist can come up with a fix.
Set the "cm^2 Factor" in tone mapping to 10
....ah, so you are using the lighting set that is included. Is there any way you can see how that is set up?
It appears from both your render and the promo image that the exterior lighting is provided by an HDRI while the light coming through the windows may be created by ghost lights just outside of them. Given the issue with ghost lights and 4.20, that could be the reason. However it wouldn't explain why the exterior HDRI isn't working. Can you do a render form the outside?
ETA:
One other idea just occurred to me. check the Environment tab to see if Dome and Scene are selected.
I have most, all maybe, of the ROG sets so I had a look at the lights.
Looks like a black map was used in the cutout opacity.
Remove that and alot of the lighting problems go away.
I just went into the textures folder and renamed it to _DISABLED_black.png so it would disable it for everything instead of doing one at a time, there are alot of them.
The bloom is a bit off now, and I'm sure a few of the other lighting settings are also.
Just changed it to 10 and not much change but it seemed to be easier for my gpu to handle as it didn't get as hot <60 and changing other settings didn't really help either until I started changing the film iso and that's when my gpu started really heating up
kyoto kid said:
....ah, so you are using the lighting set that is included. Is there any way you can see how that is set up?
It appears from both your render and the promo image that the exterior lighting is provided by an HDRI while the light coming through the windows may be created by ghost lights just outside of them. Given the issue with ghost lights and 4.20, that could be the reason. However it wouldn't explain why the exterior HDRI isn't working. Can you do a render form the outside?
ETA:
One other idea just occurred to me. check the Environment tab to see if Dome and Scene are selected.
The environment tab is set to Dome and Scene and environment intensty is .25
The image is a bit big but tried to show all the lights- a lot of fire light and emissives for the sun and a distant light. I guess I need to go check out that thread on fixes.