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sorry but i dont think that mawell i unbiased as they say..
Posted: Wed Sep 14, 2005 7:11 pm
by giacob
good renderer .. perhaps the best ... but dont think deserves to be called unbiased....non only for the enormous bug concerning the light through glass (though that would be enough)
just think , for instance, at a small kitchen with just a windows at 12 am, enlightened from just indirect light and with shutters more than half down, and glass panels at window... in real word u can see that the kitchen is more than adequately enlightened...
make a render of this kitchen with maxwell without shutters and windows glasses and u will see that the level of illumination, even after 50 hours or so , will be far lesser than in real world.....
as a see it the problem, maxweel as any other engine lack something that simulate the indirect light coming from the world around.... they better solve this problem or give us the chance of hiding from view emitters so we can use them as area light
Posted: Wed Sep 14, 2005 7:16 pm
by Matthew Schrock
Could you post your render and camera settings - we may be able to help you out.
Matthew
Posted: Wed Sep 14, 2005 7:28 pm
by giacob
Matthew Schrock wrote:Could you post your render and camera settings - we may be able to help you out.
Matthew
thats no way to be helped .. nthing cant be done

for instance do u really think that a room under such condition as this would be so dark.. i really do not think so... in real life it would be much more enlightened
Posted: Wed Sep 14, 2005 7:38 pm
by 4 HeRo
Your room should be flooded with light, the window seems big enough.
can you post the scene so we can have i look for you,
don't need to post the texture or fitting just the room ,window and blinds will do

Posted: Wed Sep 14, 2005 7:38 pm
by macray
Then adapt the shutter speed and iso of the film to the one of your eye and you get your result!
Posted: Wed Sep 14, 2005 7:39 pm
by DELETED
DELETED
Posted: Wed Sep 14, 2005 7:44 pm
by Matthew Schrock
giacob,
You've modeled a very nice scene.
Maxwell follows the concept of simulating a camera. Photographing a scene like this in real life could well result in a similar image - or something much lighter or much darker - it all depends on the real life camera settings. The same is true for Maxwell.
The question one should ask is this: When comparing Maxwell simulations with real life situations, do similar camera settings in similar light conditions result in similar images?
Matthew
Posted: Wed Sep 14, 2005 8:27 pm
by rivoli
actually that render is not giacob's, i guess he just wanted to show it as an example (btw, that room might be like that just deesee wanted it to be like that, so i doubt it does tell us a thing about how much maxwell is biased).
here's the link to the original thred:
http://www.maxwellrender.com/forum/viewtopic.php?t=5690
Posted: Wed Sep 14, 2005 8:35 pm
by Matthew Schrock
rivoli,
thanks for "shedding some light" on this "problem scene"
Matthew
Posted: Wed Sep 14, 2005 8:36 pm
by aitraaz
correct me if i'm wrong, but i don't think the biased/unbiased thing is the issue here...biased refers to the calculation method, which is unbiased, and its this being unbiased which in fact causes the problems with dialectrics and direct sunlight (clip maps)...so if there's a problem it shouldn't have anything to do with biased or unbiased, or rather the problem is that unbiased leads to an entire series of problems/bugs which are independent from speed...so if u adjust shutter and fstop darkness shouldn't be an issue...dunno...i've confused myself...
Posted: Wed Sep 14, 2005 9:03 pm
by Maxer
I think you guy's are right; this scene could look any number of different ways depending on what the camera settings are. The only way to truly test whether or not Maxwell is correctly rendering a scene is to take a picture and then reproduce that picture using the same settings.
Posted: Wed Sep 14, 2005 9:09 pm
by giacob
sorry i didnt mention that this render wasnt mine... i presumed that all the people followed all the threads as i do and that already knew that...
anyhow i was not talking about " this render is good or not" ....i just think that maxwell cant really fully simulates the behaviuor of light in real world
it is less biased perhaps , but still biased, surely not unbiased... it just on the way
anyone cant make the experiment and will see that an interior lightened with sun and phisical sky , no matter if u dont use dielettric, is much darker than the same in real life and u have to resort to any kind of triks to reach to a decent level of lighting
Posted: Wed Sep 14, 2005 9:12 pm
by Mihai
just think , for instance, at a small kitchen with just a windows at 12 am, enlightened from just indirect light and with shutters more than half down, and glass panels at window... in real word u can see that the kitchen is more than adequately enlightened...
Here's another one: Think how your eye can simultaneously see both an illuminated room and looking outside through the window, you can also see what's outside! Incredible isn't it?
Try doing that with any camera, you either get a very dark room if you want to see the outside, or you get a complete white outside if you want adequate light to show up in the interior.
I guess real cameras also cheat and are biased.......or perhaps comparing what our eyes see and what a photographic film sees is not a good comparison................................

Posted: Wed Sep 14, 2005 9:22 pm
by Prowler
@giacob
I don't get your point! If you set the ISO Level much higher the room will be much more brighter! Did you ever try to make a picture of a room with a bright window? Please try it...

Posted: Wed Sep 14, 2005 9:23 pm
by giacob
i think that even if you look not towards the windows but on the opposite side the levell of illuminations is lower than in real life...
when taking a picture in real life dont think that in such situation u would need a film with such iso levels at all