Physical camera override

[pixelstudio]

will the beginning of a script for this is made

http://www.chaosgroup.com/forum/phpB...ic.php?t=21442

[bhchllc]

I have experienced frustration before about having to go through the whole process of setting up a camera just because I want to take a quick look at something.

What would be sweet is an "auto-exposure" checkbox for the perspective view similar to the way an instamatic works. It wouldn't be perfect but close enough to atleast see what is going on. I guess it would really only work when using LC for secondary where it had enough info to balance itself prior to actual render.

[^Lele^]

I scripted an exposimeter, and mate, it's not THAT simple.
That's why I left to the user the ability to choose which portion of the "rule of thirds" to expose instead of doing the guess myself.
Simply put: what is a "well exposed" picture?
Say, all the pixels at an AVERAGE brightness of 0.5?
Easy, no?
No.
That could be all the image black (say 999 pixels), and 1 single pixel at an intensity of 500.0 float.
Far fetched?
Point the camera at the sun and expose.

[percydaman]

I did and I went blind... Oh wait, you meant the camera...

[^Lele^]

lmao, it made your eyes water, didn't it?

[percydaman]

yes, but I fought through the pain, waiting for it to expose for me.

[bhchllc]

yea, your scripts are great. Did someone suggest it was easy? I didn't.

I scripted an exposimeter, and mate, it's not THAT simple.
That's why I left to the user the ability to choose which portion of the "rule of thirds" to expose instead of doing the guess myself.
Simply put: what is a "well exposed" picture?
Say, all the pixels at an AVERAGE brightness of 0.5?
Easy, no?
No.
That could be all the image black (say 999 pixels), and 1 single pixel at an intensity of 500.0 float.
Far fetched?
Point the camera at the sun and expose.

[^Lele^]

I didn't mean to sound bragging.
I meant to say that if you could do that with a checkbox, then the physcam exposure controls would have worked automatically from the onset.
The fact of the matter is that to expose you need to render, so to evaluate geometry, lighting and shaders.
THEN expose.
It can't be done without at least one render.
And even then, i daresay there's no "auto" exposure that will work in just every situation.

[bhchllc]

Its all good. I didn't take it as bragging and even so, you of all people have the right to

It has got me thinking about the algorithims "auto-exposure" mode uses on high-end cameras. Looking at the 5D, it supports:

Max. aperture TTL metering with 35-zone SPC
(1) Evaluative metering (link to all AF points)
(2) Partial metering (approx. 8% of viewfinder)
(3) Spot metering (approx. 3.5% of viewfinder)
(4) Center-weighted average metering

I can certainly see how this is no easy scripting task but it makes me wonder just how the camera "decides" what is right. More often than not, it gets pretty damn close, particularly with the extra range you have in RAW format.

[^Lele^]

Yes indeed.
I have been thinking, and side-coding, some new bits to enhance the exposimeter.
While not quite exactly as you described it, the ability to change the percentages for each square (or slice) of the thirds already gives you some freedom to choose what to expose.
Multi-point AF, and a better mimicking of real-world dslr, is in the pipe, along with some early concept to Z-weight exposure.
It won't be there very soon, but it'll get out eventually (and dare I say it, possibly commercially too.)

[pixelstudio]

i'm not even trying to auto-expose lele's script work very good doing it.