any tips on how to speed up dof are greatly welcome.
( does DR slow down DOF-Calculation? )
now i use fixed rate sampling and area filter. dof is partly done in ps.
andre
Hehe, we will always recognize our gaussian blur
āweā āourā ?? do we have some PS programmers in here?
all i can say is thats one damned refreshing looking glass of beer there. on a nice summer day like this it hits the spot
I was just meaning we can easily recognize the PS gaussian blur vs true DOF calculation.
Donāt u ?
If you want to tweak a DOF on a still (Working with anim under a few conditions).
- Export you Z on another channel (gray) or by using RPF or RLA (donāt forget to use the coverage for edge bluring).
- Use this gray image as a mask for a blur layer into your prefered comp software or in PS.
Dirty and quick, as always. 
Cheers
By the way, I love your render, but the little beer drops look a bit too crisp for me (IMO).
If someone would create a PS plugin that uses the Z mask to give the blur radius information, we would have much better faked DOF !
Because a blurred layer masked on a sharp one makes realy unreal DOF :?
ive written a tutorial on that before. at 3dluvr on faking dof with z-buffer
Canāt find it 
3dluvr search engine is currently off
it was a basic tut i wrote a while back. basically you load a z-buffer into your images alpha channel then in photoshop under selection choose the alpha channel as the selection and when you use blur with that it will put the blur radius based on the alpha channels values. using your curves you can alter your alpha channel so that you have a focus area where close things would be blured, then a focal range in the middle of the shot then out of focus again in the distance.
in my tut i use fog actually rather than z-buffer. basically because the z-buffer is not reflected but fog is.
put it this way. put a tiny red sticker on your mirror. focus your eyes to that sticker. everything else in the distance reflected in that mirror wont be in focus. With the z-buffer. the mirror would be the depth of that greyscale and it wont calculate the depth of the objects reflected. Basically my tut tried to address that problem. But like i said its a simplistic tutorial
ps dont shoot me!!! the tut was written in October. and vray was released for beta testing in december
Nice tut,
but again, we can see blurred edges going on sharp ones by transparencyā¦
Combining lots of layers attenuates thisā¦ but the problem still remains
BTW, ur alpha channel isnāt used for blur RADIUS, its used for transparency, thats all different.
There is no plugin using a mask for the radius itself.
I pray for someone to create one, it shouldnt be impossible isnāt it ?
(It means creating some āproceduralā effect layer, where the result depends on whatās under the effect layer - this doesnāt exists in PS)
do u understand what i mean ?
the z-buffer workaround wonāt blur the droplets on the backside of the glass. i really like the vray dof, but in this particular case it took 8 times as long as without. iĀ“m not sure but i think the image just gets too oversampled, even in places where you wonāt notice it.
the drops: they are the whole point of the exercise. iĀ“m trying to combine procedural maps to get a ārefreshingā look.
Could you please explain how you create these drops? Itās displacement right? But how do you it? On which surface is the displacement applied to so you can give only the drops a water (beer) material?
thanks for any tips
flipside
there are a few plugins that create DOF effects with z-buffer data in PS.
the best is imo LENSCARE, i can hardly see a difference that would justify the extra rendertime.
http://www.frischluft.com/Lenscare/Gallery.html
especially look at this:
http://www.frischluft.com/gallery/Lenscare/MuscleCar.html
is this vray or faked:
is this vray or faked:
I would say that the focus points are a little bit wonky (Iām no expert)
Since the focal area seems to be the center ship, why
would the plank to the left be so sharp when the ship in front of it is out
of focusā¦ conversely, the plank directly under the focused ship is
defocused some, when one would expect it to be as sharp as the legs.
Subtle cues are all that it takes to make the mind think something
is not real, imo. Although, there is always a tradeoff between
rendertime and deadlines.
Being a hobbyist, I can also afford to be a purist.
I really like the plank material, as well as the feel of the scene,
however =)
i think thats no problem.
the ships have a hight.
so the top of the ship is closer to the camera then the bottom.
that would bring the top more out of focus.
not?
flipside: you clone the surface that you want drops on, assign it a drop material and add a displacement modifier. i used waterlevel to cut the drops and cellular as a 3d map.
andre
Thanks andre!
What actually does that water level do? I just clips of the lowest part o your surface? Or do you use alpha channels or something to remove the non-drop part of your cloned surface?
Thanks,
flipside
it clips the mesh
flipside: imagine you want green slimey drops on a glass, but you donĀ“t want the drops to intersect the glass. here you use waterlevel to clip the mesh.
you can always use maps to mask areas, or blend displacement-maps.
andre