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trisen
01-22-2004, 07:56 AM
Here is a bottle of BeeR. Render time 8 hours. No plugins was used. Just rendering another image with a Beer botlle and a beer in it. Will post it soon.

veljko
01-22-2004, 11:11 AM
Cool image,
the theme is a bit dull, but never the less expertly done!

For your next image, maybe try to liven it up a bit- add a bowl with precels in it!-
or something like that,

trisen
01-22-2004, 11:24 AM
Tnx for a reply =))) here is my next rendered image =))) It would be grate to read some criticks on it =)))

wacom
01-22-2004, 11:28 AM
Looks great! Excellent materials! However...

If you're using a "slow" computer please igonore what is written down under:

Maybe I'm a fool or impatient or each put together but why did this take 8hrs? Is this a smaller image of the final render?

Sorry- I know LW is slow...but it just seems to me that people don't "optimise" things like they used to. Can you show us a wire frame, and what you did? Is everything getting raytraced reflections, radiosity, and hyper caustics, HDRI lighting, etc on it?

I'm not trying to rub you the wrong way...I just think we could at least get your render time cut in half.

trisen
01-22-2004, 12:10 PM
Last image rendered 17 hours! And here is a reason:
1. All model is subpatch. I used displasment map for the herb and a sign on the bottle, so for good result I made subPatch level to 24 to get a good displacment/
2 I used ray recursion limit of 12.
3 I used Digital combusion for blur/

o here is reason of slow render.

wacom
01-22-2004, 01:43 PM
Originally posted by trisen
Last image rendered 17 hours! And here is a reason:
1. All model is subpatch. I used displasment map for the herb and a sign on the bottle, so for good result I made subPatch level to 24 to get a good displacment/
2 I used ray recursion limit of 12.
3 I used Digital combusion for blur/

o here is reason of slow render.


First things first-
This image looks great!

OK...

1-Why don't you freeze your sub-patched bottle at a lower res- then go into the small area where the herb is and sub divide (not sub patch)that until you get the density you need? I understand the need for the high poly count in that area- but subpatching the hell out of the whole bottle is your #1 reason your render times are so freaking high! The diffrence between the two methods can be as dramatic as going from 10,000 quad polys to 70,000 quads or more (and I'm betting you've got more quads than that). Just something to think about.

If you must use subpatches there are ways to get around this problem. Please post your mesh and tell us the sub-patch detail level you are using.

2- Is there a real reason you need raytrace recursion at 12? Have you rendered at a lower resolution to see if there is a big change between say 4 and 12?

3- If you own DF or DFX+ you could save your self a lot of time by rendering out an RLA and using their depth blur. You can then do it in post and get just what you need. That would speed things WAY up. Just don't use adaptive sampling on your AA settings.

4- It looks like you're using HDRI images or "image lighting". No? Well if you are you might want to try and selectivly turn off ray trace reflections for some of your materials and experiment with the reflections that the HDRI image will give you alone using image world. Many people get great results and save oodles of render time using this method for glass and metal objects.


Just somethings to try- I'll bet you can get this to render in an hour or less with some major tweaking!

Still- those are some damd fine bottle pictures you've got so don't trash them!

otacon
01-22-2004, 02:21 PM
Nice render. Is the second pic supposed to have beer in the bottle, because i really cant tell the difference between the two. Beer would have a different refraction index, which would make it stand out in the bottle because of the way the light passes through it, also the color would be different.

trisen
01-22-2004, 02:24 PM
WOW Wacom I have got more new information about rendering time redusing I will try to comlytly redus my time !!!
Big TNX!!!!!!!!!!!!!!!

BTW: about number of ray recursion 12 is the minimum in tgis scena cause if it <12 there is another caustic no realistic =|

Ramon
01-22-2004, 08:34 PM
Great image! Good job.
Only thing that looks a bit off is where the bottle meets the table. It seems like there should be more of a shadow right along the edge there.
Keep up the great work.

Simon
01-25-2004, 04:17 AM
Hi. To add to the above, if you're not viewing the bottle from the side, you don't actually need to see any extra geometry for the label and embossed mark, so you don't really need a displacement. I bet just a simple bump map would do, then knock down that subpatch level from 24 to about 5 or 6.

Ramon
01-25-2004, 01:00 PM
I'll second what Simon said and raise it one:
Unless you are going to do something extreme, like fly the camera into the creases of the seal, then a bump map will be the answer and in which case, you can drop the Subpatch division to I would say 4 and get a great bottle and drastically increase your render time.
Simon is correct, all you need is a bump map. However, even if you animate the bottle turning at the distance that you have shown us, all you may need to show that the embossed area of the seal is raised is an area of polys that are tightly conformed to the seal bump map that you smooth shift out just slightly.

BTW, great image as I said but, I don't know if you noticed that 3/4 of the way up from the bottom of your image map to the right, there is a horizontal line that seems to cut the reflection. I don't know what that could be.

Anyways, I hope that would work for you.:)

Ramon
01-25-2004, 01:10 PM
This line "cut" is on the bottle. I didn't clarify in my last post.

wacom
01-25-2004, 01:45 PM
I was wondering why you needed to do a displacment instead of just a bump map as well. Maybe I should have asked that before going off. Whoopsie!

I agree that modeling out that area a bit would probably be your best bet if you need to view the bottle from angle that will show this area. The thirty minutes to and hour it would take you would be more than made up at render time!

wacom
01-25-2004, 01:47 PM
Oh and also- did you try experiementing with the caustic acuracy and level settings? You might be able to bump these up and get what you need while decreasing the ray trace recursion level.

CiaranM
02-20-2004, 04:34 PM
Really nice render you have there mate!
Further to the advice regarding displacement maps:
If you feel you must use a normal displacement rather than a imple bump map, I just learned a speedy trick. The really slow part of displacement mapping is the polygon normal detection - this takes ages. So instead use a morph map as the displacement direction. In modeler, create a morph of your bottle and smooth scale (NOT smooth shift) the morph, making it perhaps 2mm larger - this represents the height of the displacement. Now, in the Layout displacement controls, change the direction from normals to morph and select your morph from the list. 1M displacement will now represent 100% of the smooth scale.
This should help save you a bit of time!