Welcome to our community

Be a part of something great, join today!

  • 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 :)

Idea: use a 3D rid to simulate HDRx

Erich Ocean

Well-known member
Joined
Dec 5, 2008
Messages
764
Reaction score
0
Points
0
*typo alert* It should say "3D rig" in the title.

So, it occurred to me that a 3D rig could be used to shoot HDR 2D images. Here's how it would work:

- "A camera" shoots at 24fps 180deg, normal exposure
- "B camera" shoots at 96fps 90deg, highlight exposure (just like HDRx)
- both cameras are in a 3D rig, but NOT stereoscopic

Basically, this is another way to get the HDR track, the difference is that you have "more" samples for the highlight exposure track. Other variations are possible, such as shooting "HDR" at 120fps on both cameras. This would be identical to what the Epic does in camera, but at a much higher frame rate.

Anyway, an expensive way to get HDR, but in principle, any two cameras that can be sensor-synced could get HDR, dual-track, Epic-style photography this way.

Thoughts?
 
Sweet!

So between what the Epic does, and what can be done with two cameras -- something that cannot be done with film (well), digital cameras have more than won the "latitude" war. And with Epic, the resolution war has also been won.

Epic-X. Can't. Ship. Fast. Enough.
 
But Epic goes to 11

spinal-tap.jpg
 
Funny thing about dynamic range... 1st thing people do is grade it out.

Jim
 
This idea has been around for a while, (or at least it has in my head too),

alot of work to achieve what epic does with that nattress magic button in redcine, lol.

however, imagine 2 Epics in that same rig,

whats that, 22 stops of lattitude? i dont think you need anymore do you?
 
That's because the 'film look' is all about crushed, blown images dontchaknow....
 
Funny thing about dynamic range... 1st thing people do is grade it out.

Jim

I feel like this is very true for narrative work, but for nature and underwater work I feel people tend to leave it...
 
Funny thing about dynamic range... 1st thing people do is grade it out.

Jim

That's true but you still gain much more control of your "hip, 300-esc, contrasty" image when you started with 18 stops than if you just start and finish with 6 stops from an older video camera. If you start with 18 stops, you can finish with most of your highlights and the important parts of your shadow detail intact, where as when you used to shoot with a 6 stop camera, you get (other than a lighting nightmare) enough latitude to either have your shadows in tact, or your highlights intact, or neither, or if you lit it properly, you get a bland evenly lit scene that looks kind of pixel mapped when you try to raise the contrast.

I've been experimenting with ganging two cameras together (one set for highlight protection, the other set for black protection, both shooting through a beam splitter) and combining the images for years, but I can't wait to shoot 18 stops on one compact camera and then crush the blacks in all manner of extreme ways!
 
Yes, Jim, you are 100% correct. For all the fury and fear, the very first thing they do is get rid of it. It is baffling. Thanks for giving it to us anyway.
I've worked with at least 100 DPs in the last three decades, and "more density" is a common request in the color-correction room. Darkness and drama help tell the story much more than lots of exposure. And this was with the 14+ stop range of film.

The best thing HDR will do is avoid unnecessarily blowing out white detail and crushing black detail in principal photography. Later on in post, the director and DP can make the creative choice as to whether they want to include or exclude these details. Not all of the film look is about crushing or blowing out; I can think of lots of recent Oscar-winning films and shorts that did neither. Good-looking photography doesn't have to be about extremes.

I don't see this working well with 2 cameras simply because of the weight, the expense, the doubling up of data, and a lot of other logistical problems. Me personally, I'd say the camera already has an ASA of 800 -- that's gonna get you through some pretty extreme exposure situations if you're careful and know what you're doing. (Big If's.)
 
Does anyone know (maybe from RED?) if 2 Red MX on a 3D rig for HDR , produce more dynamic range of 1 Epic in HDRX mode ... i have few shots to make that really require as much as is possible to get ...(but unfortunately 2 Epic would be to expensive as far as today ...(rental will be quite HIgh until E-X will be out in big quantities....

thanks
 
2 RED MX could almost certainly produce more usable DR than a single EPIC, even with HDRx. Of course, running two EPICs in a rig could do even more, an insane amount more if they had HDRx on with 3 up to even 6 stops of highlight protection.

My biggest peeve with "HDR" imagery is that most of it is nothing more than oddly-graded, harshly tone-mapped imagery. Many "HDR" photos we can pull up online, especially video shot in mirror HDR (aka stereo) rigs are not using the latest cameras and often have less usable DR than what a single R1MX can give us! People tend to associate "tone-mapped" with HDR or even being HDR. And that's really not the case. There is also no standard as to what constitutes "HDR". Personally, I think it should just be a loose term that states you are using a method to achieve more DR than what is available from whatever imaging system you're using can offer under conventional use. If you're using a Nikon D2X to do three sequential exposures for HDR, you may be able to achieve about 13~15 stops of usable DR. OTOH, a Nikon D3X can approach 14 stops of usable range on a single exposure. Definitely something to consider there. And the first example with 3 exposures, when combined by typical "HDR" processing methods and mentality, will look funky, unnatural, even cartoony.

IMO, this is where RED's (Graeme's) magic HDRx hot sauce is really great. They are doing a perfect job of blending the exposure tracks to keep color tones natural.

Marc's point about darkness and drama is spot-on and should be considered heavily. More DR does not always make for better images. It can give more exposure range to play with in post. HDR is handy, especially in a form like HDRx, for those times when you have too much contrast and no way to control or capture it to get the shot. But at some point, you still have to take that range of exposed imagery and compress it down to fit within viewable color space. It may not always be pretty when that is done. Ultimately, for narrative work, as Marc said, it's better to let darkness and drama, even blown out highlights, work for you to help tell your story and pull a viewer's attention where it needs to be. There are times when everything properly exposed in a frame is just boring... Perhaps that's why many people find all the cartoony and super-glossy, over-saturated, tone-mapped fakey HDR to be so attractive?
 
i agree with you 100% jeff,
People tend to see HDR a """cartoon""" effect , in my case i need it for a particular setup where i need the very highest DR possible to simulate the Human eye (like literally being there ) , and i am wondering if i should complicate "my life" using 2 MX and the 3D rig or use just one Epic .... i mean, i need to get the best effect as possible , but i kind of wondering how many more usable stops 2MX would give me more than 1 epic....(and when i say usable i mean to produce a properly balanced image (nor weird cartoon effects...)

thanks

g
 
I was just thinking the other day about the possibility of having a mini beam-splitter behind the lens, in place of, say, a rotating mirror OVF, and two sensors in one camera body to achieve HDR. One sensor in the normal position and one above with ND or lower sensitivity. It would cut out a bit of overall sensitivity since the beam-splitter would take up some light, but you could gain a lot of highlight detail, and no motion artifacts since the shutter speed would remain constant across both. Probably have to have global shutters to avoid rolling shutter artifacts , too. Just a thought.
 
Did a test for a short the other day, used 2 MXs in a beamsplitter. The results were great but the weight was too much. Ended up using one camera with a low con filter, not as much DR, but if properly processed the results are equally interesting.
 
Back
Top