Topics

76

[Max] I need help! / Caustics - Fireflies - again

« on: 2020-10-11, 21:46:17 »

I cannot get rid of the fireflies created by reflective caustics.  Simple scene, sunlight, pool, building.  It's a villa on a tropical island so think white walls, clear blue sky, bright sunlight.

The annoying part is the refractive pool caustics looks great, it's the reflective caustics onto the building from the pool causing the fireflies.

I've tried sun/sky, hdri, environment caustics on, environment caustics off, caustics adaptivity on, caustics adaptivity off, still frame computation, animation computation.

Fireflies always there regardless of what I do.

I can't post many screenshots due to NDA's, but I've mocked up the scene setup, the blue bubble is where I get the fireflies

 

77

[Max] I need help! / UVW Randomizer

« on: 2020-09-15, 15:38:25 »

What is the above actually doing?  I thought it just shifted the UV coordinates of each 'item' or whatever you choose in the drop down.

Anyway see attached.  On the left, just the bitmap, on the right, same bitmap inside a UVW randomizer with the settings as shown.  The 'weird' effect is different depending on whether you choose 'Primitive', 'Mat ID', 'Instance', 'Mesh Element' etc etc

On the geometry I have a UVW Map set to Box with 'Real World Scale' turned on.

Corona 6

78

[Max] I need help! / Reflection Override Issue

« on: 2020-05-27, 14:58:31 »

Please see attached, can anybody explain why I get this harsh dark shadow transition when I enable reflection override, doesn't matter if the reflection override is white/black or a jpeg.

It's lit with a simply sun and sky system.

79

[Max] General Discussion / Need some help from the Techies

« on: 2020-05-05, 23:08:02 »

So I've just added a 3990x to my arsenal.

As things stand I currently have 3 boxes

Xeons Box - E5 2640 v3 (x2) - this is old
i9 Box - i9 7980XE
Threadripper box - 3990x

I've just tested a quick scene.

Before today I was working on the i9 Box and sending DR renders with the Xeons joining in.

So here are my rendertimes.

i9 on it's own - 19 mins 9 seconds

i9 with Xeons DR - 13 mins 40 seconds

i9 with Xeons and Threadripper DR - 9 mins and 36 seconds

i9 with Threadripper DR - 10 mins and 49 seconds

I then fired up the scene locally on the Threadripper and it rendered in 8 mins and 34 seconds.

The Threadripper on it's own was the fastest option.  I don't understand.  Has adding the Threadripper just made my other two machines completely redundant in terms of rendering?  Is it that fast that the other 2 are hindering its capabilities?  Or have I got a problem somewhere?  Network maybe?

80

[Max] I need help! / Strange Geometry Mid Render

« on: 2019-11-27, 23:43:13 »

So I'm just testing some basic white card views on a new model.

After any random number of passes - the attached happens - this was after 46 passes, I've just tried again and it did it after 15 passes.  The highlighted band seems to become either reflective or transparent, I can't quite work it out.

Up until that point it renders aboslutely fine and looks perfect.

At first I thought it was the extreme shift/clipping through glass somehow becoming visible again, but I've tried hiding the glass too and it makes no difference.

I've also attached how it looks just before the artifacts appear.

81

[Max] I need help! / Corona 5 - 2.5D Displacement on Curves

« on: 2019-11-07, 14:48:08 »

Anyone know why my displacement goes funky when it reaches a curve?  The exact same material on both the flat surface and the curve?

82

[Max] I need help! / [solved] Anyway to edit default settings for Corona Maps i.e. Corona Bitmap

« on: 2019-09-30, 13:46:09 »

As the title suggests, is there any way to edit any settings files anywhere, to control the default values for Maps.

For example, everytime I load a Corona Bitmap, I change the Interpolation to Bicubic Smoother.  It would be nice if I didn't have to do this every single time.

83

[Max] I need help! / Shadowcatcher Issue

« on: 2019-09-09, 20:46:20 »

First problem - when I choose 'For Compositing' as the Alpha Mode - why does my ShadowCatcher object not render black?

Second problem, is there any way to exlude things to avoid doubling up of shadows etc?

I've attached a backplate I need to composite into.  I basically need to place a car in the shaded area of the road, and a car into the sunlit area of the road.

I've modelled the road, and I'm projecting the backplate onto it using the shadowcatcher material (is this correct).

I setup lighting using a simple sun/sky system to emulate the conditions in the backplate.

I've modelled the building that's casting the shadow across the road as I need to get that same shadow on the car and the reflections from it (this is the problem shadow - I don't want this shadow on the shadow catcher, just on the car, because well it's already on the backplate).

Is this possible?  Where am I going wrong?

84

[Max] I need help! / Shadows to Match Backplate Geometry

« on: 2019-07-22, 20:39:19 »

I doing a photomontage at the minute, I need to make sure that my CGI shadows fall correctly on the existing building in the photograph.

I've modelled the existing building in 3D so that it receives the correct(ish) shadows.

Is there any way to have this geometry hidden in the render, but the shadows cast onto it visible in the shadow pass for overlaying in post?

Or is there a way to achieve what I'm trying to do

85

[Max] I need help! / Render Time Boolean - Distance Map Issue

« on: 2019-07-11, 16:28:15 »

See attached, I've some really complexed shapes/panels to make so was hoping this would work, but as you can see in the image, my booleans are 'hollow' is that makes sense.  I need the resulting borders to be bridged together so the red part still looks solid

The basic setup is the same as this, just without the 'inside colour' object as I want it all the same colour/material

https://forum.corona-renderer.com/index.php?topic=13210.0

86

[Max] I need help! / Caustics Making things Darker

« on: 2019-06-11, 22:24:44 »

This isn't necessarily an issue relating to V4 (although I am using it), but I've noticed this previously too.

Can anyone explain why enabling refractive caustics (Caustics 'Slow' in the material), makes things appear a lot darker.

Screenshot attached with absorption colours and light strength exaggerated.  The only setting to change between the two screenshots is the Caustics being enabled in the water material.

Disabling 'cast shadows' in the object properties gives a completely different look again - although I know this isn't really a correct setup.

Just looking to understand why this happens so I can rectify it.

87

[Max] I need help! / DR Hangs on Save before Render

« on: 2019-04-19, 14:31:41 »

So my scene file is pretty large - just over 4GB.

If I save it to the NAS it saves fine, takes less than a minute.  As soon as I press Render though, it does the autosave which I believe it needs for DR, and then hangs at this point?

Any ideas?  Are there any file size limitations with DR?

It's not memory issue

88

[Max] I need help! / HDRI reflection strength

« on: 2019-02-26, 08:45:36 »

Can anyone with a bit of technical knowledge explain why some HDRI's are way too strong in reflections and some are way to dull.

For example, I often find getting the lighting/exposure right with PGSkies results in super bright reflections, but yesterday I was experimenting with the Poliigon HDRI's and found the opposite.  Once lighting and exposure looked correct, the reflections were incredibly dull?

89

[Max] I need help! / Corona Bitmap - Real World Scale Display

« on: 2019-02-14, 23:17:33 »

Is it a known issue that Corona bitmap doesn't display textures correctly when real world scale is used inside the bitmap

90

[Max] Feature Requests / Corona Bitmap - 'Keep old map as sub Map'

« on: 2019-02-08, 16:45:37 »

Is this possible, if I have a standard bitmap in a map slot, and then I decide I want to use the Corona Bitmap instead, it'd be nice if it allowed me to use the existing bitmap as a sub map, rather than automatically opening explorer and forcing me to navigate for the map again and then redialling in all my scaling/tiling settings.