Depth of Field in Combustion

[whitewash]

I was playing around with a demo of comubustion over the weekend and was particularly excited by the ability to do DOF as a post process, by rendering to elements or an .rpf file and then using the zdepth channel as a basis for a compound blur on the image channel.

 

My own experiments have shown that it definitely works, but it seems to look, err, a bit crappy. It's maybe good enough quality for a video, but not for a still.

Has anyone had any luck doing this? Can you do something similar in photoshop?

 

Cheers

 

Paul.

[Bugga_Guy]

I don't know about combustion. But in Photoshop with your z depth image - make a seperate layer in the channels group and paste your z depth b/w image there. Then under blur filters use "lens Blur" and select the channel layer with the z dpeth image. Play around with the settings until you are happy.

[whitewash]

your z depth b/w image there. Then under blur filters use "lens Blur" and select the channel layer with the z dpeth image. Play around with the settings until you are happy.

 

Aww, crap. No lens blur in my copy of Photoshop 6.

 

Hmmmm...

 

Is the effect any good? i.e. an acceptable substitute to doing DOF in 3d? Maybe it's finally time to get that photoshop upgrade...

[Bugga_Guy]

its good in the fact you can control your DOP in real time, and adjust the amount you see fit, instead of doing a whole bunch of render tests.

[Jim Mann]

You will always have more control and flexibility doing this in post.

 

I don't really use combustion for stills but I make heavy use of the RPF format to add DOF, motion blur and the like to animations in post.

 

That said, I am currently working on what is effectively an animated still where the camera is locked down but there are people and other animated elements moving within the scene and am using combustion for this.

 

Jim

[Jeff Mottle]

I've found the exact same thing with Combustions XDOF....kinda crappy. Try using the commercial MAX plugin called XDOF.

[Crazy Homeless Guy]

I don't know about combustion. But in Photoshop with your z depth image - make a seperate layer in the channels group and paste your z depth b/w image there. Then under blur filters use "lens Blur" and select the channel layer with the z dpeth image. Play around with the settings until you are happy.

 

how are you getting your z-depth image? ...i am using photoshop 7. it doesn't read RLA or RPF files. does CS read these? ...or did you manage to write the z-depth in a standalone file like a tga?

[Bugga_Guy]

how are you getting your z-depth image? ...i am using photoshop 7. it doesn't read RLA or RPF files. does CS read these? ...or did you manage to write the z-depth in a standalone file like a tga?

 

Well my method with photoshop is a cheap and dirty trick, it will only work with the "LENS BLUR" filter under Blur. I use CS, so I don't know if this is in PS 7

 

To extract a zdepth image in max goto Render scene dialog box, goto render elements. under add Pick Z-depth, and render. The image will look like a fuzzy black and white image. Save that image as a tiff/tga (or whatever) (you can also save automatically by selecting element parameters, and specifiying a filename/type.

 

Yeah, RPC are a problem, I was hoping that it wouldn't come up..... RPCs in zdepth are represented as boxes... So my only solution is to render the RPC on a seperate layer then manully blur them.. so NEVER USE RPCS WITH ZDEPTH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Crazy Homeless Guy]

Well my method with photoshop is a cheap and dirty trick, it will only work with the "LENS BLUR" filter under Blur. I use CS, so I don't know if this is in PS 7

 

To extract a zdepth image in max goto Render scene dialog box, goto render elements. under add Pick Z-depth, and render. The image will look like a fuzzy black and white image. Save that image as a tiff/tga (or whatever) (you can also save automatically by selecting element parameters, and specifiying a filename/type.

 

Yeah, RPC are a problem, I was hoping that it wouldn't come up..... RPCs in zdepth are represented as boxes... So my only solution is to render the RPC on a seperate layer then manully blur them.. so NEVER USE RPCS WITH ZDEPTH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

no lens blur in photoshop 7. it must be a CS thing. a reason for an upgrade. ...i didn't see the render elements at first because i am using vray, which allows you to save z-depth, but i am struggling with it. all i can seem to manage is a really screwed up image that looks psychedelic with lots of rings, and a strange yellow color.

[Bugga_Guy]

Getting Z depth shouldnt be difficult, and it shouldn't have colour (as I am aware) It looks more like an b/w xray of the image that you are producing. the closest objects.. I don't use Vray, so I can't help you out too much. But the thing is, you can use a scanline render to make out your zdepth image. Since it needs no colour, just switch the different renders, and keep the same camera angle. So you can render you image in Vray, then your zdepth image in scanline render (as long as you use the same camera)....

[Crazy Homeless Guy]

Getting Z depth shouldnt be difficult, and it shouldn't have colour (as I am aware) It looks more like an b/w xray of the image that you are producing. the closest objects.. I don't use Vray, so I can't help you out too much. But the thing is, you can use a scanline render to make out your zdepth image. Since it needs no colour, just switch the different renders, and keep the same camera angle. So you can render you image in Vray, then your zdepth image in scanline render (as long as you use the same camera)....

 

thanks, that worked.

 

while 7 doesn't have lens blur, you can manipulate the depth blur to some extent by pasting into the alpha as you describe, then doing a selection with the alpha, and inverse the selection. this will give you a faded selection into the depth of the image. then use gausion blur to adjust to you liking.

[Bugga_Guy]

Interesting... FYI CS's lens blur - its a wicked fliter, within it you can even add noise to the DOF, and a few other tidbits here and there. I recommend getting it.

[Ernest Burden III]

i am using vray, which allows you to save z-depth, but i am struggling with it. all i can seem to manage is a really screwed up image that looks psychedelic with lots of rings, and a strange yellow color.

 

There is a poor-man's way to do this that I developed for Lightscape, since it lacks a Z buffer output option. It's a bit of work, but the results are quite good.

 

Copy your model under a new name. Open all materials (great if you can do them all at once, which Cinema can, LS couldn't) and make everything white, no diffuse channel or maps. You can leave shine, specular if you like, but the resluts will be different. Otherwise, ideal diffuse (LS term).

 

Use a fog function and make the fog black, adjust to taste. Raytrace, best if you can do that to a 16bit (aka 48bit) render.

 

Now, if you leave transparency and shininess on your objects you will get those properties in the render, it can be quite convincing to have glass reflecting the grayscale depth.

[MrCAD]

hello ernest,

 

Here's a small test sample I made for DOF on a lightscape render. Its done using drapefx..drapefx finds its own zdepth info from the 3d imported data.

 

http://www.forumdesk.drapefx.com/viewtopic.php?t=33

 

I'll post a small video tut of its working soon,

 

 

Meher Thakker

http://www.mr-cad.com

http://www.drapefx.com

[Ernest Burden III]

Here's a small test sample I made for DOF on a lightscape render. Its done using drapefx..drapefx finds its own zdepth info from the 3d imported data.

 

OK, I'll bite. What is DrapeFX? Can it read Lightscape files?

[MrCAD]

Sorry for the late reply Ernest

 

Well Drapefx cannot read lightscape files so the method is import your .ls scene in 3dsmax and export to .df from 3dsmax. Drapefx uses 2 files for loading 1 image file (can be .jpg, tga, tiff etc) and 1 .df file. The filename should be the same and both the files in the same folder. You simply need to load your image file and it will read the .df file automatically.

 

Anyways I've made a small kitchen dof demo .wmv file for you to understand the working.

 

http://www.drapefx.com/video/kitchen-dof.zip

 

There's one more video scene I made for users to understand the use of drapefx for architectural visualisation.

 

http://www.drapefx.com/video/arch.zip

 

Btw..the build available for download on the website still does not have the dof feature .. I will be adding the new build by next week.

 

cheers

 

Meher