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I want to see triple exposure video


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I know RED as well as Z-cam has implemented this. Z-cam's implementation doesn't work with a lot of motion, not sure about RED.

Lightroom mobile enables DNG Triple exposure photos on my old Iphone, its amazing how nice the pictures look. I want to see Triple exposure video, even if its just 1080p. People are saying M43 is outdated but I'd be all over it if they did something like that. 

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Or how about a hybrid of the technique:  Three quick consecutive bracketed exposures x24fps?  Anyone know the reasons why that wouldn't be implemented in M43?  That's not simultaneous triple exposure, so it would have certain motion blur issues, but seems like it could be done via firmware?

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3 hours ago, thebrothersthre3 said:

I mean even double exposure video is great. Implemented on a M43 sensor at 2k you'd have a ton of highlight and shadow information. Wish there was more a push for this technology. 

Exactly. 

IMHO, it was one of the biggest accomplishments of Magic Lantern. 

Canons back then didn't have the best dynamic range, but implementing Dual ISO to them changed that. 

Even now many of these videos look gorgeous, almost Alexa-like. 

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7 hours ago, leslie said:

just line up three cameras together and blend in post ?

If you can tear @BTM_Pix away from his chocolate bars he could rig something to fire them of together i'm sure 😁

As you can see, I'm managing to combine both at the moment.

I do have a couple of ideas about how to do something interesting regarding the multiple exposures but not necessarily conventional approaches....

Bench.thumb.jpg.3ec6fc60f0ee32163eed8b8c6d89f6a3.jpg

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Isn't the problem with more than one exposure the inability to use it with any sort of movement in the frame? If your subject doesn't move or change, you already can do multiple exposures. 

The obvious solution is better dynamic range so you can capture better pictures in demanding constrasty situations. 

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17 hours ago, kaylee said:

sorry, I don't understand, what do you guys mean by "triple exposure video"...? how would that work, and for what purpose...?

There is a bit of overlap in terminology, so It's confusing.  By "triple exposure video," I think that OP intended to mean "HDR video with three different exposure levels."

 

Historically, the terms "double exposure" and "multiple exposure" meant exposing a single piece of emulsion in-camera, two or more times, to combine different images into something like this:

relander-6-768x658@2x.jpg

 

With digital imaging, the multiple exposure process is a little different, because each exposure is a separate image and, thus, a separate file.  Some digital cameras offer various ways to combine files and to create multiple exposure images, such as the Canon 5D mkIII and the Olympus OMD cameras.

 

Undoubtedly, most who create "multiple exposure" images today are combining the images in post/editing.

 

 

On 3/18/2020 at 12:00 AM, heart0less said:

IMHO, it was one of the biggest accomplishments of Magic Lantern.  Canons back then didn't have the best dynamic range, but implementing Dual ISO to them changed that.

Magic Lantern offers two HDR video methods:  Dual ISO (which you mentioned) and HDR video.  I don't remember which method appeared first.

 

ML's Dual ISO is a technique in which every other row of pixels is given a different exposure/gain.  So, for example, all "even" rows are given a darker exposure while all "odd" rows are given a brighter exposure.  The separate exposures are "blended" to make a single HDR image.  This method can induce aliasing/moire.

 

Our own @ZEEK made a video tutorial on setting up a Dual ISO raw video on a Canon EOSM:

 

Incidentally, "dual ISO" has morphed into a term for more recent cameras featuring a sensor that can be "set" to one of two native ISOs.

 

On the other hand, ML's HDR video simply gives a different exposure/gain to every other frame.  For instance, every "odd" frame is given a darker exposure while every "even" frame is given a brighter exposure.  This technique doesn't suffer the aliasing/moire of ML's Dual ISO, but I seem to recall reports of motion artifacts.

 

By the way, prior to ML's Dual ISO, Panavision touted their Dyanmax HDR sensor which was claimed to feature three different, nested pixel arrays, with each array having a different exposure (somewhat similar to ML Dual ISO).  Panavision has remained mysterious in regards to why they abandoned the idea (and subsequently sold their sensor foundry).

 

 

On 3/17/2020 at 6:36 PM, leslie said:

just line up three cameras together and blend in post ?

It was done in 2010 with two Canon 5D mkII's and a beam splitter (probably the mirror type):

 

 

Here is another early method from 2011 with a single Canon 7D and a post process:

 

 

For three cameras, one could possibly use a prism beam splitter.  If one could put the beam splitter and three shallow-mount cameras in a light-tight enclosure, it might be possible to use a single "taking" lens.

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Yeah HDR using 3 different photos shot at three different exposures. 

Most sensors now can do 10 stops of dynamic range easily. If you combined three photos at three different exposures you'd have something with more dynamic range than an Alexa I'd say. I'd imagine its just a matter of a processor/sensor that can take three photos at the same time, if thats possible. 

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2 hours ago, tupp said:

It was done in 2010 with two Canon 5D mkII's and a beam splitter (probably the mirror type):

 

Yes looks every bit as bad as expected...

Honestly looks like total muck.

Contrast is your friend.

Look at lighting in Citizen Kane.

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8 hours ago, thebrothersthre3 said:

If you combined three photos at three different exposures you'd have something with more dynamic range than an Alexa I'd say. I'd imagine its just a matter of a processor/sensor that can take three photos at the same time, if thats possible. 

Other than the camera/sensor mentioned by @androidlad, scientific and machine vision cameras likely exist that have a greater dynamic range than an Alexa (and an A7S).

 

The Panavision Dynamax sensor supposedly took three different exposures, which yielded a 120dB DR.

 

 

7 hours ago, Andrew Reid said:

Yes looks every bit as bad as expected... Honestly looks like total muck.  Contrast is your friend.

I usually don't make qualitative judgements on the results of such early tests, especially since whoever blazed this trail into HDR was a pioneer, lacking the benefit of years of HDR tweaking by others who subsequently jumped onto the HDR bandwagon.

 

However, I wouldn't call it "bad" nor does it seem to be "muck," lacking in contrast.  It seems exceedingly "Dragan-esque," with an unnatural, tone-mapped feel. It's actually interesting, but not the look into which HDR eventually developed.

 

 

7 hours ago, Andrew Reid said:

Look at lighting in Citizen Kane.

Obviously, they weren't striving to match the look of "Citizen Kane" (which is a phenomenal film, by the way), nor were they trying to apply "ideal" lighting.  They were merely testing a new idea.

 

Please give them a break. 

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Triple exposure HDR is awesome though you can always bring highlights and shadows up or down to get whatever look you want. What I have on my phone is also RAW dng which I think contributes to how nice the files are. That Sony sensor looks awesome tho, they should put it in a body like the Zcam 

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Looks like you're getting the triple exposure feature you want:

https://www.mediatek.com/products/smartphones/dimensity-1000

Quote

World’s First Multi-Exposure HDR video

The Dimensity 1000 is the only smartphone SoC that can record 4K HDR video by capturing every three frames at different exposures and intelligently fuses them into a single video stream, all in real-time. The results are unprecedented, allowing users to accurately capture the full spectacle even in environments with extremes of bright or darkness, regardless of whether it’s a single moments photo or a video of the whole event.

 

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