Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: lius86 on 2015-02-27, 18:04:05

Title: DOF in new version
Post by: lius86 on 2015-02-27, 18:04:05
Hello guys,

I can't use the camera properly as i was doing with the old version.
I understand, that if i want to be able to change the exposure from the buffer, i need to DON T apply the corona camera mod, but if i do that, i can't control the DOF as before.

Another very useful and amazing thing about Corona, was the ability to control the DOF intensity, being able to fake a focal lenght, and then change the F values.
I can't find this option anymore...i feel lost!

Thanks
Title: Re: DOF in new version
Post by: lius86 on 2015-03-02, 10:33:45
uP!

Still not figure out..
Title: Re: DOF in new version
Post by: romullus on 2015-03-02, 10:47:21
How to use exposure controls:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000517792-how-to-change-exposure-during-rendering-
https://coronarenderer.freshdesk.com/support/solutions/articles/5000515620-how-to-use-photographic-exposure-controls-

How to use DOF controls:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000516203-how-to-enable-and-control-depth-of-field-dof-in-corona-

Hope this helps.
Title: Re: DOF in new version
Post by: lius86 on 2015-03-02, 11:33:38
How to use exposure controls:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000517792-how-to-change-exposure-during-rendering-
https://coronarenderer.freshdesk.com/support/solutions/articles/5000515620-how-to-use-photographic-exposure-controls-

How to use DOF controls:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000516203-how-to-enable-and-control-depth-of-field-dof-in-corona-

Hope this helps.

Thanks,

But where I can find the sensor size option with the new version?

Edit: ok, got it, so basically if i want to be able to control the DOF, I need to activate the DOF in the render settings (before i was doing from the camera modifier) , and if I want at the same time to control the exposure during the render, I will need to activate Photographic exposure.

Basically, I don't need to use a corona camera modifier on the vray cam anymore...is that correct?


Thanks
Title: Re: DOF in new version
Post by: romullus on 2015-03-02, 12:08:43
But where I can find the sensor size option with the new version?
I wouldn't recomend to use sensor size for DOF control. Use F-stop spinner instead.



Thanks,

But where I can find the sensor size option with the new version?

Edit: ok, got it, so basically if i want to be able to control the DOF, I need to activate the DOF in the render settings (before i was doing from the camera modifier) , and if I want at the same time to control the exposure during the render, I will need to activate Photographic exposure.

Basically, I don't need to use a corona camera modifier on the vray cam anymore...is that correct?

Yes, you have to enable DOF in render settings in order to render it and no, you are not forced to use photographic exposure if you don't want to. You can use arbitrary exposure control via EV spinner and have control over DOF at the same time.

And CoronaCamMod isn't necessary for all this as it wasn't required in previous versions too.
Title: Re: DOF in new version
Post by: Archvis on 2015-03-02, 23:06:18
I can't get DOF to work very easily either.

Is there a tutorial?

I've checked on all the right boxes, and put my target in the right position, played with f-stop etc.

I did an exaggerated render and set F-stop to 0.01 and that did show results but finding the right number is painfully tricky.

Is there a way to incorporate a real time DOF so what you see is what you get?
Title: Re: DOF in new version
Post by: PROH on 2015-03-02, 23:44:24
Hi. If you're using v1 and follows the description from Rommulus last post, then it should show in the IR. Don't use Max's DOF and f-stop settings in the Camera. Use the settings in the Render Setup, scene tab (or use a Corona CamMod).

Hope it helps
Title: Re: DOF in new version
Post by: lius86 on 2015-03-09, 20:36:09
Hi. If you're using v1 and follows the description from Rommulus last post, then it should show in the IR. Don't use Max's DOF and f-stop settings in the Camera. Use the settings in the Render Setup, scene tab (or use a Corona CamMod).

Hope it helps

But how do you change the F number being able to use free exposure?
THe only place where i can see the F number settings, is under photographic exposition, but i don't want to use it!

got it:

https://coronarenderer.freshdesk.com/support/solutions/articles/5000515620

We can change the exposure from the settings even while rendering, just amazing!

THanks
Title: Re: DOF in new version
Post by: PROH on 2015-03-09, 22:05:29
Hi lius86.

Just to clear things up: It is actually possible to use "free" exposure and f-stop setting. You don't have to activate "photographic exposure" to use the "f-stop" settings - even though it is placed in that box. As long as it isn't greyed out, it's active.

Hope it helps
Title: Re: DOF in new version
Post by: lius86 on 2015-03-10, 11:08:29
Hi lius86.

Just to clear things up: It is actually possible to use "free" exposure and f-stop setting. You don't have to activate "photographic exposure" to use the "f-stop" settings - even though it is placed in that box. As long as it isn't greyed out, it's active.

Hope it helps

oh that's very useful!!!not really user friendly though..

Thanks!
Title: Re: DOF in new version
Post by: Rimas on 2015-03-10, 12:30:53
Although the usage is clear to me personally, one thing that bugs me a lot as a photographer is that the default 'sensor width' is set to 35mm...
35mm film (or full-frame digital) size is actually 36mm x 24mm - that's 36mm wide, not 35.
Title: Re: DOF in new version
Post by: Ondra on 2015-03-10, 13:09:27
I will look into why everybody uses "35 mm", and possibly change the defaults.
Title: Re: DOF in new version
Post by: romullus on 2015-03-10, 13:24:36
Look no further: http://en.wikipedia.org/wiki/35mm_format
Title: Re: DOF in new version
Post by: lius86 on 2015-03-10, 13:39:40
I will look into why everybody uses "35 mm", and possibly change the defaults.

35mm is the popular name for full frame sensor size, http://en.wikipedia.org/wiki/35mm_format

I would probably keep it for Corona..

I just notice a little "bug" in the DOF system, if you see the reflections on my cabinet, show the chair and table out of focus, but actually, that plane is on focus, so, the reflections shouldn't be out of focus.

what do you guys think?
Title: Re: DOF in new version
Post by: Ondra on 2015-03-10, 13:41:59
it is actually correct - you can see the same behavior in real world
Title: Re: DOF in new version
Post by: lius86 on 2015-03-10, 13:44:44
it is actually correct - you can see the same behavior in real world

yes actually i am thinking about that since 1 hour, and i am not sure about the answer..i am gonna test it!!! :)
Title: Re: DOF in new version
Post by: maru on 2015-03-10, 14:03:14
The easiest example to imagine for me is when you are looking into a viewfinder of a DSLR - the mirror is very close to your eye, yet you see a sharp image. Or you can just use some ordinary mirror. If you place non-reflective object close to your eye, it would get blurry.
Title: Re: DOF in new version
Post by: Rimas on 2015-03-10, 14:12:01
It is correct. Imagine a mirror surface as being a 'window' that extends to your reflected objects. That creates distance, which is now out of focus.

As for the '35mm' defaults - width-wise the number is incorrect and should be 36mm. I'd expect to punch in 36mm width if I was matching a rendering to a photograph/video from my EOS 5D Mark III (or 22.2mm for EOS 60D) just like a cinema professional would expect to punch in 70mm width to simulate an IMAX frame.
It says 'frame WIDTH', not 'film standard', in which case 35mm could mean Cinema 35mm standard (3-perf), which is actually only 24.9mm wide!
That is confusing right there!

Which brings me to another question... Does the current DoF scale measure correct for 36mm (36mm in the setting calculates 36mm) width or is the default 35mm actually calculated as 36mm?
Title: Re: DOF in new version
Post by: Ondra on 2015-03-10, 21:32:22
yes, it should be 36. Corona uses that number directly (well.. converts it to scene units first). So by default it uses 36mm. There are some approximations involved in the model of ideal thin lens camera, so I dont know how well it matches real camera DOF (if the ~3% difference is not actually lower than some other error produced here)
Title: Re: DOF in new version
Post by: Rimas on 2015-03-11, 10:23:00
Sorry, I got confused a bit by the answer :/
So do I leave 35mm setting to get 36mm DoF or do I do as I do usually and input 36mm myself?

Thanks!
Title: Re: DOF in new version
Post by: Ondra on 2015-03-11, 14:04:43
input 36mm by hand
Title: Re: DOF in new version
Post by: Rimas on 2015-03-11, 14:10:48
Got it, thanks! :)