[Rogurt]

Hi all

I thought I knew what I had to expect when diving into unbiased renderers. But the render times I come across are soooo huge that I really get puzzled. I searched the forum/manual/web high and low for advice on correct setup of a scene to render reasonably in maxwell (like avoiding object intersection with emitters; using AGS Glas etc). Then again for a mostly directly lit scene with 6 emitters it took my little render farm (around 28 cinebench) 16h to get to sampling level 20 at 1500px x 1500px.

edit: SL was only around 16 and it was far from cleared

Unfortunately there are no rendertimes/machine specs mentioned in the galleries. Else I could get an impression wether these times are normal.
Can anyone tell me where to find such examples with durations?

Cheers,
Rogurt

[Rogurt]

Meanwhile I found that there´s Benchwell for an orientation. Or it should be there. The weblink routes to domain resellers and ads. Has it moved?

Regarding V Ray there are tons of renderings with rendertimes out there. Why is that? Or have I just not found the "cases with rendertimes" subforum here yet?

Can U guys bill your clients half a week it takes to render a mini size picture?

Still very confusing.
Rogurt

[Half Life]

Maxwell can be blazing fast or maddeningly slow depending on exactly what you are trying to render -- there are lots of rules but generally exterior architectural scenes (Physical Sky or IBL) and studio-type product shots (lit by IBL) can be lightning fast... where interiors with lots of emitters will be one of the slowest to render.

Each emitter adds to the time Maxwell will take to calculate, that's just the unbiased reality... and multilight will increase that render time significantly. There are things you can do to mitigate those issues somewhat but it will always be slower to render.

There's tons of posts in regards to these topics and using the search function of the forum is sure to shed light (pun intended) on the issues. I personally made my peace with render times long ago... I do get sick and tired of the endless monotonous griping about render times, my concern is quality first, second and last -- I have very little time for the "Maxwell needs to be faster" crowd.

Also, you would likely get more responses had you not posted this in the wrong forum.

Best,
Jason.

[Bubbaloo]

We could probably help you better if you posted a rendering or even a scene to look at along with your machine specs. A general statement like "Maxwell is rendering slow" isn't much to go by.

[Rogurt]

Thanks for your response. I guess this is really not the best place for the question.
I have searched some hours on "render speed" and "optimize" and such here in the forum (and the manual of course). But somehow I haven´t come across the "multilight is slow and the more emitter the slower" statement. So thanks for that!

I have used multilight to creatively mix my light setup and put a bunch of lights in the scene (5 one-poly-planes and one maxwell library light object for which I modeled a shade). No funky emitter seetings used like 1000000 Watt or such.

The image rendered to approx. sampling level 16 in about 40 hours on 5 Machines with Dual Xeon E5520, 8Gb RAM.

http://www.william-associates.com/tmp/k ... emix.3.jpg
edit: new pic, old was accidently linear colorspace

Cheers,
Rogurt

[Half Life]

Here's a thread started by another user which contains alot of tips and answers in one place:

http://www.maxwellrender.com/forum/view ... 97&t=36085

Alot of those answers and information would apply here as well.

Best,
Jason.

[Rogurt]

@jason thanks for the link. The bits and pieces I found elsewhere are here neatly together in one place. that would also mean, that there´s no more room for "optimizing"? When I looked through the settings in Studio I thought maybe I´d want to set the caustics setting to "direct only" or "none" if there´s no real impact on the look of the scene. Do you guys do such kind of tweaking? Does that make sense?

I found that the RANCH benchmark and calculation tool would really help one to get an impression of whether some project can be done or not (regarding the time a customer will wait for it and if that time can be billed).

Still I havent found benchwell out there in the net

[numerobis]

http://www.maxwellrender.fr/public/benchwell_scene.rar
http://visualim2.o2switch.net/benchwell/

[Half Life]

There's always room for optimizing the way you assemble the scene -- that's where you can be pretty tricky to get the results you need.

Just because something is not set up totally physically accurate does not mean it won't still look good... just think about all the behind the scenes stuff that is present in your average Hollywood film(cameras, lighting, sound, director, other actors, etc), but if it is done with skill we still "buy in".

For instance the scene you show would be better set up as a studio (photography) shot using HDR for most of the off camera lighting (I use the HDR Light Studio Plugin for Maxwell Studio because setup is fast with excellent feedback via FIRE)... you would see a dramatic speedup at that point. Thinking too literally can really mess things up when you are trying to sell something -- almost all product photos are completely contrived.

Best,
Jason.

[djflod]

don't want to be picky but ...

could anybody move that off topic threat out of the gallery ??

[Rogurt]

Thanks again for ll your thoughts!

Cheers
Rogurt

[Mihai]

and multilight will increase that render time significantly. There are things you can do to mitigate those issues somewhat but it will always be slower to render.

Jason, are you sure about this? I haven't seen much longer render times just because I turned on ML so I'm wondering how you arrived at this conclusion? Also the more emitters you have in the scene doesn't necessarily mean longer render times. It depends mostly on the lighting situation, a scene with lots of indirect lighting will render slower.

Rogurt, would be best if you could post the scene, or send it to me privately. The image you linked to above doesn't work. If you haven't already, please read this section of the online docs:

http://support.nextlimit.com/display/ma ... +you+begin

That has about all you need to take care of in terms of optimizing your scene. 40H for a 1500x1500 is not normal...any other features you used in the scene like displacement, SSS materials etc?

[Half Life]

Jason, are you sure about this? I haven't seen much longer render times just because I turned on ML so I'm wondering how you arrived at this conclusion? Also the more emitters you have in the scene doesn't necessarily mean longer render times. It depends mostly on the lighting situation, a scene with lots of indirect lighting will render slower.

Rogurt, would be best if you could post the scene, or send it to me privately. The image you linked to above doesn't work. If you haven't already, please read this section of the online docs:

http://support.nextlimit.com/display/ma ... +you+begin

That has about all you need to take care of in terms of optimizing your scene. 40H for a 1500x1500 is not normal...any other features you used in the scene like displacement, SSS materials etc?

I have definitely seen longer render times particularly for color multi-light but it has been a few versions since I used the feature so maybe things have improved since... I just got in the habit of not using it at all because it would drive up the render times and I generally don't need it. I can go back and take a look again to revise my observations.

I've always found the practical downside of emitters is that they do add render time/ noise level (which are the same to me) because they complicate the lighting scenario -- but it's not a 1 to 1 relationship and obviously emitter size and power play into this but that is more information than I thought would be pertinent to a discussion with a newer user... I was painting the picture in broad strokes. There is no doubt that IBL or Physical sky will render/clear faster than any emitter... and of course we have had issues with bugs and emitters in the recent past so that may have contributed to my general observation.

Best,
Jason.

[Half Life]

Very interesting -- obviously something changed massively while I wasn't looking because not only does Multilight not slow down the render but it actually speeds it up (at least on my test scene) although it scores a lower benchmark overall (how is that possible??)

And even more surprising Color Multilight is still faster than a regular render (even with a much lower benchmark??) -- and obviously all things being equal it would be best to use Color Multilight all the time.

I am curious why this is the first I've heard of this improvement -- it seems like that would be pretty big news around here.

Best,
Jason.

[Mihai]

AFAIK regular ML never added much to the render time, you should test this with more scenes in my opinion. When you just say that simply the NUMBER of emitters mean longer render times can also be misleading for a new user because in some scenes having 5 or 100 emitters will not necessarily mean a lot longer render time, in fact in some scenes it can be beneficial to place an emitter which when turned on slightly can 'hide' some of the noise coming from difficult indirect lighting. Maybe best to move this discussion to another thread and we can show some comparisons. I'm interested to see your test scenes and why before it took so much longer just having ML on.