Rendertime with detail enhancement

[fAEkE]

I just made some tests with and without detail enhancement and the difference in rendertime was more then I expected. I made a region render on a A3 300 dpi interior shot.

DMC AA sampler set to 2/12 and 0.003 threshold. IM high preset -4/-2 and 175/60. LC 1750.

With detail enhancement on default (world instead of screen scale), the render took 11:21, and without enhancement it took 01:50. That is a huge difference. I'm not used to working with detail enhancement, so I don't know how many subdivs it needs. What do you guys use?

[Morne]

I usually leave it at deafult

[simmsimaging]

I just made some tests with and without detail enhancement and the difference in rendertime was more then I expected. I made a region render on a A3 300 dpi interior shot.

DMC AA sampler set to 2/12 and 0.003 threshold. IM high preset -4/-2 and 175/60. LC 1750.

With detail enhancement on default (world instead of screen scale), the render took 11:21, and without enhancement it took 01:50. That is a huge difference. I'm not used to working with detail enhancement, so I don't know how many subdivs it needs. What do you guys use?

What was the multiplier for DE set to? That can probably make a huge difference, particularly with such high sub-divisions in your IM. I think default is possibly too high for that.

[fAEkE]

It was set to default. 0.3 I think? I also tried 0.05 with better result. The same render quality and 05:00. But it's still too much difference in rendertime. 01:50 to 05:00? :/ I get why ppl use AO pass. Maybe I should try even lower values.. I have no idea how many subdivs detail enhancement need to look decent.

[simmsimaging]

When using my variation of the Universal method I usually have the BF sub-d's at around 15 but sometimes even less (like 8-10). So you are pretty close with .05 It's definitely slower than without, but you'll have to decide if it's worth it or not. Often I can't even tell when it's on, but I think it's highly subject and light dependent.

/b

[fAEkE]

I can't see any difference at all when rendering car interiors with alot of lights, but in a white interior room there is a huge difference with detail enhancement enabled. But tbh I think I can get the same effect with AO. A bit more time in post but it's worth it if rendertimes increase this much.

[joconnell]

It's possibly being caused by your DE settings being influenced by your high aa and dmc settings - I found that using a dirt pass in an adaptive dmc render as an extra text element slowed things down a bit since the dirt was being influenced by settings I needed for clean edges and grain free materials which probably pushed it into rather slow territories. Instead using an override light material with the dirt map (24 subdivs) and adaptive subdivision on something like -1,2 absolutely flew along. It's handier to have a render element with the ao embedded but you can take advantage of a lot of extra speed if you split it up!

[Subburb]

some tips about DE :
- if you've a too large radius, it can take very long to render, and give some grain (try screen 40 pix @ 800*600, 80pix @1600*1200, and so on)
- to know the real subdivs of your DE, here's the formula : de subdivs = DEmultiplier*hsph*globalmult
(note : DE multiplier is depending of hsph subdivs and global mult)
if, let's say, you want 24 subdivs for DE, and let's say again, your hsph is 50 and your global mult is 2:
then to obtain 24 subdivs for DE : DEmult = 24 / (hsph*globalmult) = 24/100 = 0.24

so each time you change hsph or globalmult, you'll need to recompute the correct de multiuplier to keep your 24 subdivs.
Hope it helps !

[fAEkE]

@jaconnell
Ye, I guess the DMC AA sampler is making it more difficult than it should be, as usual.. AO pass should do the trick tho.

@Subburb
I used 60mm (world) for a 5000px interior image. Nothing in the image is closeup so DE should only be calculated on a small part of the image.
Ye I know how to calculate the actual subdivs, but the question is how many subdivs DE needs. But as joconnell said, the AA sampler makes it all much more difficult to grasp. I guess it's all about trial and error :/

[Subburb]

sorry for redondant info.
you're right it's hard to find the correct subdivs/size ratio....

[fAEkE]

No need to apologize. Too bad DE takes so long to render.. white interiors rendered with IM/LC rly lack contact shadows.