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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Its time to introduce a HDRI workflow

S

sandeep

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I've been waiting and waiting for the the next generation of cameras to incorporate some level HDRI approach to their capture.

If its anyone listening out their to users it will have to be the red team.

we are already getting a great burst rate with scarlet and the bandwidth is there perhaps a +2 -2 exposure compensation could be incorporated and a auto step down on shutter speed. Hard drives are getting better. Just have to put our minds to it.

Lets rewrite the chapter on cinematography.

cheers
 
Been thinking on this for ages

Been thinking on this for ages

Shameless Plug:
osiris19.deviantart.com

I dont know if I want you all seeing that.... but anyway, I've just started to touch on the HDR process, and I was thinking about it for video, but how the heck would it work... can anybody explain it?

Final (link)

and element documentation

Breakdown (link)

requires multiple shots from the same perspective.... rendering alignment for one frame alone takes ages... as for a whole RAW film??? and a stereoscopic rig... or even having two sensors in the same camera.... you still get the same aperture and exposure unless they are rated for different ISOs.... or you can just process one set of images for highlights one for midtones and one for shadows and coposite them all I GUESS..... but man,...


I want to hear more about this... please discuss!
 
(H)IGH (D)YNAMIC (R)ANGE - ITS F*#ing neat, if nothing else.

(H)IGH (D)YNAMIC (R)ANGE - ITS F*#ing neat, if nothing else.

http://en.wikipedia.org/wiki/High_dynamic_range_imaging

or for an WAY better explanation....

http://www.cambridgeincolour.com/tutorials/high-dynamic-range.htm


involves compositing multiple shots of the same image taken at different bracketed exposures and applying certain tonal mapping / averaging to specific parts of the photo .... (highlights, midtones, shadows, color ranges etc.) to create a certain look... i dont have quite a handle on it yet... better to read from the above links...
 
It cannot work for video. You cannot do it via 3D because of the axis parameters. You would need to make a camera with an optical splitter and paths to 2 or more sensors. Then each sensor would need to be individually DSP'd with image controls for exposure, etc with independent outputs to separate storage devices. On top of that you would need to be able to apply digital filtration to portions of the each sensors frame, to get the desired outputs needed to take advantage of the final composites.

Better than inventing this new HDR camera would be to light your subjects properly, use excellent lenses and filtration, a nice matte box and Apple Color.

This works for still images because you can re-bracket the shot with different exposures, filtrations, etc to make a nice composite HDR in the end. Unless you master freezing time, you will not be able to re-bracket in motion pictures outside of virtual images.
 
"this works for still...." Meaning the HDR Process.
 
HD Bubaloo said:
It cannot work for video. You cannot do it via 3D because of the axis parameters. You would need to make a camera with an optical splitter and paths to 2 or more sensors. Then each sensor would need to be individually DSP'd with image controls for exposure, etc with independent outputs to separate storage devices. On top of that you would need to be able to apply digital filtration to portions of the each sensors frame, to get the desired outputs needed to take advantage of the final composites.

Better than inventing this new HDR camera would be to light your subjects properly, use excellent lenses and filtration, a nice matte box and Apple Color.

This works for still images because you can re-bracket the shot with different exposures, filtrations, etc to make a nice composite HDR in the end. Unless you master freezing time, you will not be able to re-bracket in motion pictures outside of virtual images.
Click to expand...


there you go... you used all the right words.

thanks = D
 
Why can't it work for video? Don't they do this already? I'm thinking of a shot from Forrest Gump, where they filmed several shots and merged them together to get the clouds to move faster... It's basicaly the same thing, isn't it?
 
No Wizard its not. Thats just a straight composite using plates. Meaning two completely different frames with portions matted out and framed for the final composite. Then a plate is shot and composed for the other portion of the composite ala Parent Trap or Forrest Gump.
HDR does not use plates or mattes but rather uses two different exposure settings and filtration to make the composite.

A straight composite using mattes and plates is easy. HDR composites for motion video or film is impossible (unless you can freeze time) I suppose if you have access to a black hole and some excellent timing, you can theoretically do it but its very complicated to arrange something like that. So I am told.
 
But with Scarlet we will be able to do very nice green screens which will allow for HDR to be used for matte paintings and other elements. Make no mistake Scarlet is a game changer and will allow for indie movies to look better then ever before. A large portion might not be very good but they will look better ;)
 
Better explanation of the Forrest Gump shot your talking about.

You shoot the bottom portion of the frame of Forest running with a hard matte or plate blocking out the top portion of the frame. Then you shoot the top portion of the frame with the bottom hard matted out or with a plate. You take the two shots and optically (or now via DI) merge the shots into a final composite.

HDR does not do any blocking or plating of the master shot and its composite shot. It is essentially a locked down bracketed shot with one exposure setting or filter (usually an ND grad, or color grad) and sometime focus setting, and then you shoot another identical shot but with a different exposure setting or filter (usually without the filter), sometimes focus setting. After you take both photographs (which are framed identically, due to being locked down) you merge the two into a single composite by isolating the desired portions, exposure, filtration, or focus that you want to remain, into a final picture. This is why you cannot do this with video or any moving images.

Does that make better sense?
 
aidenvfx HDR is specific to its work flow which does not use green/blue screens, hard mattes, or plates and requires the same bracketing.

Since moving pictures are just that: Moving. The subject, the camera, or both are moving. It would require repeatable camera motion control (on all ends, meaning operation, movement, etc), and if you have a subject that is living or mechanical, repeatable subject motion control. All locked and timed perfectly.

Or like I said you can just use standard compositing techniques and master tools like Color, good lighting and framing techniques, etc to get the desired look you want. HDR is specific to its workflow and specific to its process of which only apply, to still photography.
 
theoretically i think you could lock down your shot, say... of a building... or something else in which the core subject doesnt move.... and then you could HDR the crap out of it, getting really cool ghosting movements.... if i ever shoot something surreal... id like to try it.... experimentally!

if you look at the shot of the auditorium i posted earlier.... imagine people walking in front of that,... where their paths intersect, you get exaggerated tonal alterations.... not to mention the trees moving in the wind.... it could look really interesting to say the least...
 
quite right about optical splitters/ relay systems within the lens to project on other sensors. Exposure would depend on the number of sensors and perhaps re convergence back as one raw file (part on board within red).
This would be revolutionary.
Think of how much greater control you would have in DI.
Perhaps this could be incorporated at scarlet2 or 3.

There is no excuse for incorrect lighting but you simply cannot get an exposure that could read well in the dark and read in the highlights at the same time hence HDR as a post process to get all the details you couldn't get through in a single exposure.

This is possibly a new start in digital capture mechanisms away from the traditional photographic cameras of the yesterday. The next evolution of digital capture.
 
I've been thinking about how to do this for awhile. The best idea I came up with was using three cameras alligned parallel to each other. Framing would be a real bitch and you'd have to crop all the footage first before overlaying it and you'd only be left with about 2/3 of the original resolution and it'd cost a bundle and it'd be impossible to use in tight spaces, and the images would be slightly but you'd get HDR.
 
As a photographer, I'm no fan of most of the HDR stuff I see. It doesn't look real. Sometimes, but rarely, I see it done well.

You can achieve fantastic results with a graduated neutral density filter to even out the brights and shadows in a scene. No digital magic is needed, it's just a filter placed in front of the lens.
 
I suppose there is some validity to the idea of multiple sensors.... you could use smaller sensors with a much better signal/noise ratio.... you could introduce HDRI..... but i don't know the science behind image intensity loss through diffraction and the alignment would be a nightmare... yet again.. the more data you have, the richer (and potentially more time consuming) your editing is. Raw is already extremely flexible, but like.... instead of 3ccd.... Triple Mysterium? i think my head would explode...

i suppose it wouldnt matter though... who could afford it?


which is better, larger sensor size.... (1.5x reduction or some such... for those people who liked to call RED a "viable" 2k camera due to ... what was it, de-Bayering?

or greater # of sensors?


It seems to me that its too much effort for RED to waste their time as of now, but it doesn't mean its not a really cool idea, if for nothing more than an experiment.
 
I've seen some breathtaking HDRI images. I agree with you Buck... They don't look real. But ohhhhhh man they look pretty. :turned:
 
If you think the rolling shutter issue is bad, try to imagine what it would look like if you were capturing three distinct exposures of the same frame, each sequentially. Say you do it like many stills cameras do for auto bracketing: 0 -2ev +2ev

For example,
The 0ev frame would be at 0.0 seconds
The -2ev frame would be at 0.013 seconds
The +2ev frame would be at 0.026 seconds

Fine for a relatively still shot, but if there's much movement, or a camera move then it's going to look pretty funky by the time you start to build the HDRI tone-map.
 
What about an algorYthm to conDENsate for the tAmpoNal disCRAPency? :bleh:
 
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