I believe you are correct, at least that’s what I have read. It seems to work for me.
Like couldnt juju drop his to -5/-3 and still get a decent looking render?
Is there any formula/ratio list to this size/res vs. min/max rates???
I think you you can lower by 1 each time the resolutions doubles…mmm saw it somewhere let me look… ahhh ha
hehehe its in your own thread!!! 4th post from the bottom by s0real
http://www.chaosgroup.com/forum/phpBB2/viewtopic.php?t=11791&highlight=resolution+min+max
that’s bad when the answer lies within your own post. I’m going to go find a rock to hide under now:
Flipside mentioned -3, 0 at 800x600 in that post but it was mentioned here that 0 doesnt allow for undersampling.
yes but I was wrong.
Well it does and it doesn’t 
If the samples were set to 0,0 then there would be no undersampling. At -3,0 some parts of the image will be undersampled at -3 ( pixels/4 samples), -2 , -1 and then 0 ( 1 sample per pixel) depending on the threshold values. Atleast that is how I understand it…
where’s that rock again?
I am under it studying
edit: ok maybe that is right 
up there ^
Guys, IMHO with this size of a rendering (2900x1900) set IRR map to “very low” preset or even faster like ~-5;-3.
It makes no sense to add such a fine detail to the big print sized 11x17. Lots of those IRR map tiny details get lost in print and under your textures 
anyways.
I recommend IRR settings:
- “very low” hsph 60, interp 35 (to smoothen things out - cause you`re using low settings).
Then I would fiddle with QMC:
- starting from adapt 0,9, noise 0,005 and going up when needed. I would leave the min samples at their default here or even strike it to 10.
Remember, bigger renderings do not neccessarily need higher settings! (IMHO - basing on my experience)
Cheers!
It’s pretty easy really. -3/0 means that:
- in pass 1 (-3): IR map is calculated for the image at /8 its size (2*2*2). So for an 800*600 image the first pass is calculated for 100*75.
- pass 2 (-2): Info of pass 1 is used, and refined for the image at /4 size
- pass 3 (-1): Info of pass 2 is used, and refined for the image at /2 size
- pass 4 (0): Info of pass 3 isused, and refined for the image at full size
So the undersampling lies in the first 3 passes. The last pass is not undersampled but since it uses the info of the previous passes it doesn’t need to refine the GI in all areas. (vray knows where the ‘difficult’ GI areas are, and only if they don’t meet up to the thresholds like clr and dist, there will be taken more samples)
So the undersampling is simply used to find out where the GI needs lots of attention and where not.
This is also why the first pass can take a long time compared to the second for example. In the first pass, there is no info of a previous one available.
This also explains why too small bucket size is not good for IR map caclulations. Vray computes the IR map for each bucket, for example of size 50*50. First pass with min/max at -5/2: 50/2/2/2/2/2 ---> ir will be computed for a 1.5625*1.5625 bucket size… Not very usefull. So for high res renders where you usually use lower min/max rates, use bigger buckets!! Also each bucket needs to be adjusted to its neighbouring one to make sure you don’t see sudden shifts in GI light, the less buckets you have, the less adaptation will be needed.
A similar post of me was added to vray.info a long time ago:
http://www.vray.info/topics/t0101.asp
hi guys
here are some settings i use for all of my stuff.
i experienced that vray crashes, when i try to render a region
with vray-framebuffer enabled without taking output-settings from max.
so vray should always have ‘get resolution from max’ enabled.
the resolutions for the 3 settings are:
640*452 for quick-render
1754*1240 for medium-quality
3508*2480 for high-quality
i’m using hsv expo btw. my vray-lights are all set at sudivs 20.
my scenes also contain alot of glossy-mats.
on a P4 3.2GHz with HT enabled an interior scene renders in about 8-12h.
you may try them out and comment how they work for you
and give any suggestions for optimization.
be sure to make a backup of your vray.cfg-file before.
http://mypage.bluewin.ch/dpics/vray.cfg
greez
ale
what? What is this cfg file? Is it the same as presets but more permanent?
As for the suggestions - thanks once again. This was a very helpful thread and I appreciate all the help. I’d have to say the biggest time savers (minus the splotches) so far are:
1) reducing the diffuse subdivs on the lights to 20 (and possibly the most obvious.)
2) dropping from -3, 0 to -5, -3.
The other tips I couldn’t really measure cause the render was so freakin’ slow (many hours) to begin with.
Good to know things are working better 
im sooo drunk to understand what;s going on now…0/3? what…i cant see…juju…i wish you best luck
im getting married in 2 days…its my last time free..
bye
So what are you doing here lol??? RUN. RUN FAST. :shock:
i finish whats left of my beer, then run
take care dudes next week i shall see u as different person
hehehe good luck mate!!!
lol, congrats man 
thanks dudes…what are you all doing on line so late? im about to go and try to watch wedding crashers…
hehehe well its 2:30pm here in Australia