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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 :)

More HDRx...

Sure, that would be the most interesting part to keep...
What do you do with those few relevant questions lost in the "oh my god this is gorgeous" flow of comments ?
 
Uli Plank said:
Hi Sanjin and Gunleik,

IMHO Sanjin is right if he is using simulated bracketing and some sort of tone mapping.

I've used and tought HDR for years in photography and me and my students experimented with it as soon as we got our R1.

If you use a R3D straight out of the camera all our usual grading tools can only adapt the tonal curve globally. Tone mapping can do local adaptions. They are tricky to adjust and very scene dependent. Apart from noise, halo and saturation (which can be overcome to some degree), the main problem with this approach in moving images are fluctuations over time. We decided that it's not a valid method for serious filmmaking, but it definitely is giving different results than a file straight into grading.

Hope this explains it a bit, and I'm very glad RED discovered a better method.
Click to expand...

Uli thanks for your very good points.

Also I'll try to make HDRx like a small footage based on my example during next days.

Don't forget that Graeme Nattress is woking with The Foundry very close to implement some of their algorithms in HDRx thing.

Btw, for my HDR experiment I'll be using also The Foundry's plug-ins from FurnaceCore set:

F_DeNoise

Removes noise and grain from a sequence using motion estimation to average pixels along the direction of motion.

This reduces noise without softening the image. F_DeNoise has been used extensively on many films, lately including District 9.

LINK>>>



F_MotionBlur

F_MotionBlur uses the Foundry's advanced motion estimation technology to add realistic motion blur to a sequence.

F_MotionBlur uses the same techniques and technology as the motion blur found in F_Kronos but presents the controls in a less complex, more user friendly way.

LINK>>>



ROLLINGSHUTTER CMOS Correction standalone plug-in for AE and Nuke

ROLLINGSHUTTER is a brand new plug-in tool for After Effects and Nuke which tackles image-distortion problems often experienced by users of CMOS cameras.

Rolling shutter effects are commonly found with video cameras employing CMOS image sensors, which record every frame line-by-line from top to bottom of the image,

rather than as a single snapshot of a point in time.

As parts of the image are recorded at different times, fast-moving objects, or objects that pass quickly through frame during camera whip-pans, become distorted with diagonal skews.

Other typical distortions include image wobbles created when cameras are hand-held, and exposure problems with flashing or strobing lights.

Along with being ungainly and unwanted, these image distortions also increase the difficulty of 3D tracking during VFX post production, as the tracking points themselves can be equally affected

or not deliver accurate results.

Using Local Motion Estimation technology, we can individually correct parts of the image that are moving relative to the camera, even if they are moving in different directions or at different speeds.

LINK>>>
 
Yannick Verry said:
Sure, that would be the most interesting part to keep...
What do you do with those few relevant questions lost in the "oh my god this is gorgeous" flow of comments ?
Click to expand...

Sorry Yannick
I get your sarcasm
I didn't read through most of this thread as I have taken a break from reduser to concentrate on things
missed the gorgeous views and questions
I was just being silly about a simple notion and thanks to Jim

"It is amazing that Scarlet will be able to do that"

I'll sign off and leave you to the few relevant questions to ponder, big sloppy kiss on your lips. :thumbsup: :driving:

Peace :emote_hippie::Angel_anim:
 
Sorry for derailing the thread.

To me, HDR is when you extend the DR of (fill in camera here).
Epic does it by extending into the highlights - which makes a lot of practical sense IMHO.
Others do it through extending the lowlights, through f. ex. analogue gain prior to AD.

On stills (and in the Epic for motion) one can do it with multiple exposure readouts and merging them.

When the default sensor-range is not extended, I don't see it as HDR.

I know "visually" that HDR is refered to a kind of aestethichs, too - something like this:
http://www.mentalfloss.com/wp-content/uploads/2008/11/hdr-67.jpg
http://www.scottkelby.com/blog/wp-content/uploads/2007/10/hdr.jpg

This is a kind of HDR that I have never understood or managed to relate to from an aestethic perspective, and to me it is about the last thing I would like my images look like.
If it is this aestethics and not the effective range of a sensor one refers to when one say "HDR", I'll just drop out of the HDR discussion...

It's not for me.

Extended range is, though... -:)

Thus:
When you take an image which is well within range and make them look... good, for lack of better words, that is basically a "grade", and if you protect your range, well it is a less clamped "grade".

My definition is maybe off, and I accept that.

Cheers.

Back on topic
(and continue with that break... -:))

G
 
For sure Gunleik: for most of us "HDR" refers to what we have to work with, and not how we've used or abused it aesthetically. And I absolutely agree with your reaction to the samples. Give some people a little more rope and they'll hang themselves. Having said that, I'm looking forward to seeing what new, and perhaps groundbreaking, interpretations will be crafted from this DR.
 
Agreed (because it's true :p),

HDR is lots of stops.
Playing with gain, splitting images and re-blending them is all tone-mapping.

You can tonemap an HDR picture. You can't HDR a picture. It's not a verb. :D
 
Gavin Greenwalt said:
Agreed (because it's true :p),

HDR is lots of stops.
Playing with gain, splitting images and re-blending them is all tone-mapping.

You can tonemap an HDR picture. You can't HDR a picture. It's not a verb. :D
Click to expand...

I'm not sure that's entirely accurate. HDR technically should mean High Dynamic Range, or lots of stops. But if that was the case, the MX sensor as it stands would be HDR. HDR really means HDRBTMTPT (High Dynamic Range By Tone Mapping Two Pictures Together). But there are different ways of tone mapping. There's an ugly-ass way (that Gunliek linked to), and there's a way that matches as closely as possible to what it would look like if it was one shot with all the total DR. Red is doing the latter.

As I understand it, Red makes HDR images by taking a base image, which has 13 stops of DR (which is a nice hefty amount), and tone-mapping it with another image 3-6 stops darker taken immediately afterwards, to give the illusion of 16-19 stops of DR. Which is quite different than the sensor being able to handle 16-19 stops in one go, but with the added benefit of the (I'm guessing) unexpected pleasant side effect of MagicMotion.
 
joshua csehak said:
I'm not sure that's entirely accurate. HDR technically should mean High Dynamic Range, or lots of stops. But if that was the case, the MX sensor as it stands would be HDR. HDR really means HDRBTMTPT (High Dynamic Range By Tone Mapping Two Pictures Together). But there are different ways of tone mapping. There's an ugly-ass way (that Gunliek linked to), and there's a way that matches as closely as possible to what it would look like if it was one shot with all the total DR. Red is doing the latter.

As I understand it, Red makes HDR images by taking a base image, which has 13 stops of DR (which is a nice hefty amount), and tone-mapping it with another image 3-6 stops darker taken immediately afterwards, to give the illusion of 16-19 stops of DR. Which is quite different than the sensor being able to handle 16-19 stops in one go, but with the added benefit of the (I'm guessing) unexpected pleasant side effect of MagicMotion.
Click to expand...

And, if I understand the significance, a native 18 stop sensor image will display its signature throughout the dynamic range: the shadows will have the characteristics as will every other tone. For example, imagine tone mapping from a (imagined) crappy 6 stops DR sensor- even if you make multiple exposures that end up combining to contain a very high contrast scene, you will still have each and every part of the image displaying the character/limitations of the sensor, for example, a foreground rock in shadow might be adequately revealed, but the rock and its attendant shadows and texture will still reflect the quality of the poor DR sensor. With a native 18 stop sensor, the rock will display that superior quality/ characteristic.

EDIT: But this is maybe too extreme an example, since there is a heck of a lot you can do with tone mapping a great sensor.
 
Chris Barron said:
That barn shot is incredible! It's amazing Scarlet will be able to do that!
Click to expand...

I think you may be misleading yourself thinking that a 2/3" sensor will produce results similar to this s35 shot. Sure Scarlet will have a capability like this... but we have yet to see if it is comparable to Epics HDRx.
 
Gavin Greenwalt said:
You can't HDR a picture. It's not a verb. :D
Click to expand...

Unfortunately, some people do try to "HDR" pictures by adjusting exposures of a raw image + and - then feeding the TIFFs to an HDR tonemapping algorithm. With this artificial procedure you can end up with an ugly mess like the photos linked by Gunleik (and like TOO MANY others shown or linked during this last month's discussion of HDR). But you can't end up with a realistic image with extended dynamic range like the RED examples. The only way I know of to get the same realistic extension of DR with stills is to take multiple exposures with different shutter speeds.

I hope as RED re-trains some of us to appreciate what nice HDR looks like, people stop posting their own or other's ugly examples.

If you like that look, I'd guess you'll be able to get it if you want to push some of Graeme's sliders to their extremes. And if RED doesn't bother, someone else can take the SDK and do it. But I'd much rather see the realistic stuff first.
 
joshua csehak said:
I'm not sure that's entirely accurate. HDR technically should mean High Dynamic Range, or lots of stops. But if that was the case, the MX sensor as it stands would be HDR. HDR really means HDRBTMTPT (High Dynamic Range By Tone Mapping Two Pictures Together). But there are different ways of tone mapping. There's an ugly-ass way (that Gunliek linked to), and there's a way that matches as closely as possible to what it would look like if it was one shot with all the total DR. Red is doing the latter.

As I understand it, Red makes HDR images by taking a base image, which has 13 stops of DR (which is a nice hefty amount), and tone-mapping it with another image 3-6 stops darker taken immediately afterwards, to give the illusion of 16-19 stops of DR. Which is quite different than the sensor being able to handle 16-19 stops in one go, but with the added benefit of the (I'm guessing) unexpected pleasant side effect of MagicMotion.
Click to expand...

OK, I'm not an expert, and this is coming from a background in stills, but as I understand it:

- An HDR image file is just an image file that has greater bit depth than the individual raw files (32-bits in at least some formats, whereas many RAW files, for example, have 12 bits).

- You can take that 32-bit file and make it displayable on a 8-bit display by reducing the contrast. As I understand it, this is NOT tone mapping. It's just reducing contrast.

- You can tone map that 32-bit file and get really ugly crap that, unfortunately, has become popularly known as "HDR", but it's really just ugly tone mapping. But, tone mapping doesn't have to be ugly. It's basically just locally adjusting contrast between nearby pixels.

Obviously, we don't know exactly how RED is implementing this, but I vaguely remember a post that EPIC was going to be 16 bit, so, if that's the case, I'm guessing that Easy HDR consists of the light and dark images being combined in camera across the 16-bits of data available (possibly with a higher bit "intermediate" that then gets reduced in contrast). Whereas, for HDRx™, the combination into a single file is done on the desktop. In any case, I'm guessing that it's mostly a contrast reduction step in camera to produce a flat file, with tone mapping options on the desktop.
 
Gavin Greenwalt said:
Agreed (because it's true :p),

HDR is lots of stops.
Playing with gain, splitting images and re-blending them is all tone-mapping.

You can tonemap an HDR picture. You can't HDR a picture. It's not a verb. :D
Click to expand...

I refuse to accept you are right! I substitute my own reality on this one because being an acronym makes it easy for me to fit it (by force) into a practice. High Dynamic "Rang-ing". :smilewinkgrin:

I agree with Gunliek on this one. Extending the DR a given camera. And you Gavin, you should be banned for thinking otherwise!

However Gunliek should also be banned, because I don't agree that using analogue gain increases the DR of an exposure, it merely records more of it, or the same in a more usable fashion... the recording system is more effective.

I suppose if the front end of the exposure is read while the photosites are still "open" and gathering photons, then there aren't two perfectly discrete exposures... but at the same time there are two different exposures!

Is there confirmation either way? Are they they in same cycle with the first being a read "on the fly"?

'least we can all agree on wanting it oh so badleyyy! And that I should be a moderator. :banned:
 
Bill Anderson said:
And, if I understand the significance, a native 18 stop sensor image will display its signature throughout the dynamic range: the shadows will have the characteristics as will every other tone. For example, imagine tone mapping from a (imagined) crappy 6 stops DR sensor- even if you make multiple exposures that end up combining to contain a very high contrast scene, you will still have each and every part of the image displaying the character/limitations of the sensor, for example, a foreground rock in shadow might be adequately revealed, but the rock and its attendant shadows and texture will still reflect the quality of the poor DR sensor. With a native 18 stop sensor, the rock will display that superior quality/ characteristic.

EDIT: But this is maybe too extreme an example, since there is a heck of a lot you can do with tone mapping a great sensor.
Click to expand...

Hmm, interesting. I wonder exactly what the difference would be. Are you saying it would be in the noise characteristics? You should be able to come up with an algorithm that makes it look indistinguishable, I'd expect. But maybe not. I wonder if it'd be a valid test to take a regular 13-stop shot and squeeze it into two 8 or 9-stop shots, and combine them in HDR and compare them. But the main difference, and the one I was referring to, is that the image is comprised of two discrete exposures. (Which, as MagicMotion shows, isn't necessarily a bad thing.)

Bryce O said:
I think you may be misleading yourself thinking that a 2/3" sensor will produce results similar to this s35 shot. Sure Scarlet will have a capability like this... but we have yet to see if it is comparable to Epics HDRx™™.
Click to expand...

Correct me if I'm wrong, but I'm pretty sure the sensor size only affects resolution. So Scarlet footage should look just as good, but smaller -- unless there are other limiting factors. Have you used any of the 2/3" panasonic or sony ENG cameras? They look pretty darn nice. A little blurry at 2k, certainly not as crisp as Red footage, but those 2/3" chips knock the 5D and 7D out of the park, for my money.

Steve Wake said:
If you like that look, I'd guess you'll be able to get it if you want to push some of Graeme's sliders to their extremes. And if RED doesn't bother, someone else can take the SDK and do it. But I'd much rather see the realistic stuff first.
Click to expand...

I've seen one or two that are stylized that don't look too bad. For example:

http://www.iwatchstuff.com/2009/06/youth_in_revolt_poster_michael.php

This is a painting, but I'd bet better than even money that he used an HDR photo of Michael Cera as reference. It just has that look. But then again, maybe not. A lot of Men Who Stare at Goats kinda has that look too, namely the first shot. I'd love to learn more about how he shot it, if he used low-contrast film stock, or what.

http://www.thehdcrowd.com/screenshots/the_men_who_stare_at_goats_1.png (hmm, was definitely much brighter and had more of the HDR look on the TV screen)
 
Steven Hammer said:
- You can take that 32-bit file and make it displayable on a 8-bit display by reducing the contrast. As I understand it, this is NOT tone mapping. It's just reducing contrast.
Click to expand...

I was under the impression that it was all tone mapping, just different kinds, but I think you might be right. But I think you still need to combine 2 or more files to get to that 32-bit image. Does it count as HDR if I'm starting with a single RAW file?

As far as sensor bit depth goes, I still feel like I don't fully understand it, and how it relates to dynamic range. I know my 7D is 14-bit, and if I take a raw photo, I can recover some highlights in Photoshop, not unlike what I can do in RedCineX with Red footage (the MX is what, 12-bit?), but is that due to the sensor bit depth or DR or both?
 
Quick question: Will HDRx work with 3D? If I shoot with two Epic Xs in 3D config, can I use HDRx?
 
Well, I'm thinking specifically of using two Epic FF35s in 3D config for IMAX 3D HDRx if I can get this China IMAX film off the ground. :drool:
 
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