Camera DOF explanation?

[Activator]

+1 on how difficult it is to get accurate DOF. Even with a 3rd party plugin that provides a greyscale "preview" of the DOF, I find that what settings I "think" will work, do not look as expected. Getting the DOF I want is generally through LOT'S of trial and error. (Made easier with the real-time preview capability of plugins like enDOFin and zblur).

al35mm, you should also note that the native C4D DOF will wipe out ANY "post effect" (glow, highlights, etc.) and transparent objects will not allow the objects behind them to be blurred by the DOF... enDOFin and zblur respect the post effects and transparency, and they correctly render blurred reflections and control color bleeding.

[georgedrakakis]

I'm loving C4D's post render camera dof, but I can't quite get my head around it in regards to accurately setting target distance, front, and rear blur amounts. The camera representation for these settings isn't as clear as in other software I'm used to, and I can't quite visualise how the distances in these settings actually relate to the scene.
Thanks
hi,
although i am using dof that often, i've found out that it's much easier to set up front & real distance, on top &/or side views.
in these views you can see the planes of front & rear dof and you can actually drag the orange dot to manually place them wherever you want.
hth,
george

[al35mm]

+1 on how difficult it is to get accurate DOF. Even with a 3rd party plugin that provides a greyscale "preview" of the DOF, I find that what settings I "think" will work, do not look as expected. Getting the DOF I want is generally through LOT'S of trial and error. (Made easier with the real-time preview capability of plugins like enDOFin and zblur).

al35mm, you should also note that the native C4D DOF will wipe out ANY "post effect" (glow, highlights, etc.) and transparent objects will not allow the objects behind them to be blurred by the DOF... enDOFin and zblur respect the post effects and transparency, and they correctly render blurred reflections and control color bleeding.

Ahh, good, so it's not me just being completely stupid then? I had noticed the limitations of using it with other post effects, and the transparancy issues, but as it's so fast to render, I find it useful for scenes where these issues are not a problem.

So are enDOFin and zblur any good? Do they use ray scattering or some faster method?

Thanks for your reply.

[al35mm]

hi,
although i am using dof that often, i've found out that it's much easier to set up front & real distance, on top &/or side views.
in these views you can see the planes of front & rear dof and you can actually drag the orange dot to manually place them wherever you want.
hth,
george
Thanks George. I have been working with it in the top and side views so that I can see and possition the visual guides, but I find the position of the guides doesn't always give the results you would expect.

[AdamT]

It is a bit confusing, so I put together a little video tut on the subject which hopefully won't make it even more confusing: http://forums.cgsociety.org/showthread.php?p=4971826#post4971826

[Activator]

al35mm- I use enDOFin. I bought it because I don't use DOF that often, and enDOFin is less expensive. It works fine for my needs.

That said, I think zblur is probably worth the extra money if DOF plays a big part in your workflow. It seems to have a few more parameters to add and control DOF, and works better with reflections and transparency.

Both enDOFin and zblur give FAR superior blurring to C4D's native DOF, and they can use the C4D camera and target OR their own settings to generate DOF. They are also very fast. I believe you can get a demo to try... not sure.

Check this forum for other posts regarding DOF and these plugins.

[al35mm]

Great stuff Adam! I left a comment and rating in your toot thread.


Activator thanks for the plugin info. Can enDOFin and zblur be animated?

[Activator]

Yes, they can be fully animated.

[Activator]

Hmmmm... I'm starting a project this morning where I need to have semi-transparent planes with video mapped to them, set in a deep, z-space field. The camera will be drifting through them and "focusing" (via DOF) on individual planes as the camera moves past them.

I'm finding that enDOFin is NOT "respecting" the transparency! Any planes that can be seen through other planes do not get blurred by the DOF!! How disappointing!

Looks like I may be getting a copy of zblur today. The examples on the biomekk.com site show zblur working perfectly with a transparent plane in front of other objects.

[al35mm]

Yea I had a look at both enDOFin and zblur last night. In the vids they both demonstrate that they can work through a single transparent surface. Neither of them were demonstrated with more than one transparent surface. I think zblur looks like the better one, and has more features - more complication too. Also most of it's settings seem to be made outside of the render settings - not sure if that matters. Either way I think I too will be getting zblur. Guess I'll see you in zblur land!

[Activator]

OK. After playing around with enDOFin for awhile, I think I know what's going on with enDOFin's calculation of transparency and DOF.

If the transparent plane is in the "sharp" area of the DOF settings, then anything behind it will ALSO be sharp, even if the object is at a depth where it should be blurred by the DOF! If the object is only partially behind the transparent plane, it WILL be blurred by the DOF in the area that is NOT behind the plane, but still SHARP where it's behind the plane! Arghhh...

BUT, if the transparent plane is at a depth where it is also blurred by the DOF, then things behind it WILL be correctly blurred as well.

Does any one know if zblur will render this correctly? The example on the plugins page has two planes, and they are both blurred and objects behind them are blurred as well. But I need to know what will happen if the 1st plane is SHARP... will it blur the plane and objects that are behind it?

[al35mm]

Does any one know if zblur will render this correctly?
I just got zblur. Now bear in mind that I am new to c4d and even newer to zblur. I setup a scene with balls, pillars, and transparent planes. I seem to be getting the same results you got with enDOFin. I.e if the plane is in the sharp area, everything behind it is sharp too, even though they are in the out of focus area. Disappointing, but there is much to tweak in zblur, and I've only just started tweaking! It may just be a limitation of post effects in c4d.

[al35mm]

Here is a test image using zblur. You can see the nearest transparent planes which are both angled away from the camera, and 2 transparent planes off in the distance.

The closest trans plane on the right, is doing exactly what you described. The nearest one on the left has all sorts of wired things going on. Although it seems to have broken the DOF effect, there is some DOF through it, and an interesting interaction with the trans plane behind it.
http://www.wiziness.com/zblur_test_1.jpg

[tcastudios]

I'm sorry to say that it is my firm belief that -any- attempt to get a DOF picture, or even
less, a DOF animation out of Cinema is doomed to fail.
It is my humble opinion after gazillions of hours trying to cheat anything worthwhile
out of it.
I even have built a physically correct expression that calculates the correct DOF out of
filmformat, aperture, F-Stops, filmspeed etc.
(There is a simple offspring for VRay users of it)
But the way DOF in the end is calculated/applied in as PostFX there is no connection in any way, to get sort of close to "reality". There are still additional work by trial and error. And that is -without- any transparency/reflection involved.

As it looks, after 30min in VRay just trying it for the first time really, we have to use
3rd party render solutions for the time being.

If you look at the simple Vray pict you can see that "it is all there" without any problem.
(Sharp reflection over blurred backgound etc)
The sphere is inside a glass box.

This is not in any way a rant, rather an observation.

Cheers
Lennart

[heathivan]

If you look at the simple Vray pict you can see that "it is all there" without any problem.
(Sharp reflection over blurred backgound etc)
The sphere is inside a glass box.
Cheers
Lennart


Hotness. I haven't tried reflect/transparency with DOF in Vray yet. Thanks for the clear to read example :) The sharp reflections are impressive.

----h

[Activator]

Well, al35mm, you just saved me $90!! I tried to contact biomekk support with this question, but the support form only allows questions that are tied to a registered product serial number! Very disappointing that zblur also does not respect transparency 100 percent.

But...

tcastudios, YOU may have just cost me quite a few HUNDRED dollars!! I've been drooling over Vray, and the DOF render you posted shows me it just may be worth the money...

:-)

[al35mm]

I'm still playing around with zblur, and discovering other options and functions. You can contact them with out a serial if your select "other" for the product. It would be worth asking them (probably quicker than waiting for me to figure it out), before you plunge for vray maybe.

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