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Phil Holland
10-25-2013, 12:35 AM
A good chunk of my day these days is spent answering Dragon related questions. Every time something interesting comes up I feel compelled to share it here, because other likely have the same questions.


Today I was asked about the Carbon Dragon from somebody interested in purchasing one next month, and specifically this bit was brought up from the Red Store Epic Dragon Carbon Page (http://www.red.com/store/products/epic-m-red-dragon-carbon-fiber-w-side-ssd-carbon-fiber-and-magnesium-lens-mount):


RED DRAGON sensors have a native dynamic range of over 16.5+ stops, giving you a huge advantage in challenging lighting conditions. An improved signal-to-noise ratio gives you confidence that your picture quality will be print and cinema ready from ISO 200 to 2000. Less filters, less IR issues, and less noise gives you more opportunities for perfect exposure.


So what the heck does that actually mean and say. Well, after some projection tests I have thoughts that I want to share. Print and Cinema ready from ISO 200-2000 means exactly that. A workable image at up to ISO 2000 without any need for noise reduction. This I can confirm is true.

Interestingly enough because each scene is different you may be able to get a bit more out of a shot. I have pulled things down to ISO 50 with great results and up to ISO 4000 with decent results. If there's light hitting something in frame and it's within your raw exposure dynamic range, it's likely workable. However, much like Mysterium-X, if there's simply no light hitting something and you attempt to lift that up to the extreme you will see noise.


I've made two example clips. Keep in mind there is no curve involved here, just straight REDcolor3 and REDgamma3. Everything is just "flat". I am curious where DRAGONcolor will get us.

Clip 1 exhibits a scene that's well within the total dynamic range of Dragon's REDCODE RAW. Because of this it can be pushed a hell of a lot. ISO 100-6400 show here. 213MB

http://www.artbyphil.com/temp/reduser/phfx_Dragon_ISOTest1.mov

Clip 2 exhibits a black shirt as well as an unlit corner in the upper right hand of the frame, which creates essentially a "shadow box". Interestingly enough, you do see noise at the higher ISOs, but there is clear object separation over there. Pay special attention to the left corner where a bit of light is actually hitting as even at ISO 6400, it looks pretty damn nice. 347MB

http://www.artbyphil.com/temp/reduser/phfx_Dragon_ISOTest2.mov

In a realistic grading scenario you would likely apply a curve or somehow pull those shadow areas back down. However, I have certainly lifted visible detail midtones and highlights in the ISO 4000/5000 range with this little short shoot in the grade. I do think the vast majority of shooters are going to play in the ISO 200-2000 range though and expose accordingly. This is actually revealing itself to be a much broader range than Mysterium-X. Holding those highs and pulling down is damn impressive. Mark Toia's first footage out showcased that pretty well.

That wide dynamic range and workable latitude comes in real handy in post. In this image I exposed the subject who is in shadow at ISO 800. In the grade you can see how I utilized the extra space on the ceiling and floor.

http://www.artbyphil.com/temp/reduser/phfx_redDragon_ISOandGrade.jpg
- click for bigger image (http://www.artbyphil.com/temp/reduser/phfx_redDragon_ISOandGrade.jpg)


Well that's my weird "Dragon on my mind" midnight post. However, it is showing something new that folks would want to see. Even exposing at ISO 6400 with that level of noise you could use a slight bit of noise reduction for shadow heavy shots and make it screen ready pretty easily and yield the oversampling benefits from going from 6K to 4K in retaining detail.

Kwan Khan
10-25-2013, 12:56 AM
Thanks for sharing

paulherrin
10-25-2013, 12:59 AM
nice. one question i still have lingering in my mind is if i'd somehow get less noise if i did multiple passes (shadows/highlights) - as in, once the debayer is done to rgb, the grade potentially introduces noise/artifacts when lifting that wouldn't be there if processed at a different exposure. as in pseudo-hdr... when i first started thinking and working with red footage like 5 years ago that seemed like a good idea, but i think the consensus was that you could get it all in there, but now i'm second guessing that consensus because you're doing histogram stretching after the rgb conversion that otherwise you could just blend. now probably it's just an academic thing and there'd be no perceptual difference, but there's still stuff like banding to think about if you're really pushing values. i guess i should really test it out - that's just always been one of those nagging things i've never acted on. any thoughts?

Tom Gleeson
10-25-2013, 01:07 AM
Something I still do not understand about the Dragon sensor is that if I select either 200asa or 2000asa do I see the same spread of dynamic range in the highlights and shadows at either ASA setting or is it behaving more like the MX sensor?

Phil Holland
10-25-2013, 02:47 AM
nice. one question i still have lingering in my mind is if i'd somehow get less noise if i did multiple passes (shadows/highlights)

There's faster ways to get better noise reduction at the highest ISO values.



Something I still do not understand about the Dragon sensor is that if I select either 200asa or 2000asa do I see the same spread of dynamic range in the highlights and shadows at either ASA setting or is it behaving more like the MX sensor?

It still works the same way as Mysterium-X, although with a significantly larger dynamic range.

This is good reading on how ISO works with Red cameras:
http://www.red.com/learn/red-101/iso-speed-revisited


Since the total dynamic range remains unchanged, this effectively shifts the number of stops that fall above and below middle gray, and compresses or expands tones accordingly. At low ISO speeds, most of the dynamic range is below middle gray, whereas at high ISO speeds most of this dynamic range lies above middle gray.
https://s3.amazonaws.com/red_3/uploads/asset_image/image/50ca788526465a065300037a/iso-bars-red.png


That expansion of tones is where noise can come from and that's when you're on the higher ISO side of things within the shadows and darks.

The main advantages to using this ISO method rather than how other folks typically do it is to capture the maximum dynamic range a sensor has to offer without "destroying it" through pre-processing and also to avoid any clipping or crushing when adjusting ISO values later in post.

However, when compared to Mysterium-X the simplest way I can explain the difference is this:

Compared to the sensitivity and dynamic range of Mysterium-X (ISO 320-800 and 13-ish stops of dynamic range), Dragon produces 16+ stops of dynamic range at about 1.3 stops higher base sensitivity (ISO 800-2000). However, because of that new dynamic range you capture more highlight and more shadow information.

Right now, and without doing hard tests, I think it's the cleanest digital cinema camera on the market. Oddly enough one of the newer cameras on the market's native ISO is considerably darker than expected. Don't exactly know what's up there.

Tom Gleeson
10-25-2013, 03:08 AM
Thanks Phil for clearing that up

Marcos Montenegro
10-25-2013, 04:27 AM
As always Phil, very informative. I still have printouts of your frame guides; your contributions don't go unnoticed here.

Curious if you ever pushed the compression ratios shooting 6K to see what RED was talking about developing a more efficient compression algorithm? If so, when could you start telling the difference in IQ? How big are the less compressed files?

Eric Santiago
10-25-2013, 08:44 AM
I cant wait for the Phil RED COMPLETE Man pages ;)

I want hard cover version :)

Brian Pascale
10-25-2013, 08:52 AM
I Can't afford it, and don't really need it, but boy, oh boy, I sure want to upgrade the old Scarlet to a Epic Dragon. Okay, first I'm getting a new Mac Pro, then I upgrade the camera.

Phil Holland
10-25-2013, 11:52 AM
As always Phil, very informative. I still have printouts of your frame guides; your contributions don't go unnoticed here.

Curious if you ever pushed the compression ratios shooting 6K to see what RED was talking about developing a more efficient compression algorithm? If so, when could you start telling the difference in IQ? How big are the less compressed files?

Yep. In the .R3Ds you can see various compression ratios at play as well as multiple frame rates from 24-96fps.

The major thing I noticed were how much details seems to be held at higher compression ratios. There will need to be hard tests obviously shooting some high frequency detail to really observe what's going on, but it's noticeable right off the bat. I think the lower noise floor in the Dragon material effects this and it's pretty impressive.


Back to Tom's question. I get asked that ISO/FLUT question a lot and it's been awhile since I've made a useful graphic. This pretty much shows exactly what's going on in reference to Dragon's Dynamic Range and adjusting the ISO or FLUT when rating your midtones.

http://www.artbyphil.com/temp/redDragonGraphics/phfx_redDragon_ISOFLUTEmulation.png
(http://www.artbyphil.com/temp/redDragonGraphics/phfx_redDragon_ISOFLUTEmulation.png)
There isn't a real visible penalty on the lower ISO (-2 stop) adjustment shown here, although I imagine slight color distortion could potentially occur on out of range highlights on the top end. In my brief shooting experiences with Dragon this is where the sensor reveals some of it's more "pleasing character" as the highlight roll-off looks very organic. It has more of a "burning out" effect.

This graphic does show when at the highest ISO values why you could potentially see noise in the darkest shadows if there's no light hitting that area.


Which is essentially why in that second clip above there's visible noise at ISO 6400 in that shadow box region frame right, but no visible noise in the other corner frame left. Essentially because light is hitting it.

So to reference Gunleik here where "Dragon is more", basically if the sensor can clearly see detailed tones within the Raw View it's likely workable material. Which is why some have been saying it "sees into the darkness".

Jake Wilganowski
10-25-2013, 12:19 PM
Phil, with MX, we can set iso to 320, switch to raw view, and the histogram looks very similar, so most people say that's the "native" iso of the sensor. At what iso does dragon exhibit the same behavior?

Phil Holland
10-25-2013, 12:23 PM
Phil, with MX, we can set iso to 320, switch to raw view, and the histogram looks very similar, so most people say that's the "native" iso of the sensor. At what iso does dragon exhibit the same behavior?

Heh. Contested yet not contested point right there. It's what I would describe as is "around ISO 320". If you really look at it under a variety of lighting conditions you'll notice that it isn't exact. There's a bit more in there.

As others have said though, you'll be looking at about ISO 800 with Dragon if you're looking to emulate that Raw View. Again though. There's a bit more in there than that.

Jake Wilganowski
10-25-2013, 12:24 PM
Thanks. Very interesting. Gonna be fun!

Mike P.
10-25-2013, 01:33 PM
Graeme has also said that the 320vsRaw view is a left-over from the RED1... Realistically you'd have to look at them in linear (at whatever ISO) since that's what the camera actually records.

Phil, isn't this test less useful since there was plenty of ambient light in the recorded image (and ISO, as they say, is just meta-data)... That is to say, did you adjust the physical exposure settings in any of these clips, or are you merely riding ISO in RCXp (or am I missing something)? If that's the case (riding ISO, and not changing exposure settings) what exactly are you showing up? That the colour/gamma remain more consistent across the ISO range than the do with MX?

Brian Boyer
10-25-2013, 01:35 PM
I'm a little confused by the notation on your videos.

You have "RED DRAGON - REDcolor3/REDgamma3 - With S Curve". Across from that you have "No Curve, No Nothing, Flat".

So, I'm not sure what "With S Curve" means.

Phil Holland
10-25-2013, 01:44 PM
Phil, isn't this test less useful since there was plenty of ambient light in the recorded image (and ISO, as they say, is just meta-data)... That is to say, did you adjust the physical exposure settings in any of these clips, or are you merely riding ISO in RCXp (or am I missing something)? If that's the case (riding ISO, and not changing exposure settings) what exactly are you showing up? That the colour/gamma remain more consistent across the ISO range than the do with MX?

Well yes and no. This was exposed properly for the shot and I'm merely adjusting ISO here, but there's a variety of content across the frame. If you look at Clip 2 in the upper right hand corner that is indeed an area of "darkness". That should tell you a lot.



I'm a little confused by the notation on your videos.

You have "RED DRAGON - REDcolor3/REDgamma3 - With S Curve". Across from that you have "No Curve, No Nothing, Flat".

So, I'm not sure what "With S Curve" means.

Doh. Apologies. I left my burn in text from an S Curve test. I'll upload new ones without that typo right now. It'll take a second for them to show up.

Phil Holland
10-25-2013, 03:02 PM
Typos fixed and new versions uploaded.

I've also added one more. This clip is ISO 50-12800.

http://www.artbyphil.com/temp/reduser/phfx_Dragon_ISOTest3.mov

Again, I rated my exposure for ISO 800. What I'm essentially demonstrating is the range you have to work with within a balanced exposure. There's a lot of possibilities here. A lot.


** edit. One last additional clip. This one has a rather distinct and large dynamic range as there's deep shadow content as well as well lit. ISO 50-12800

http://www.artbyphil.com/temp/reduser/phfx_Dragon_ISOTest4.mov

Nick Wernham
10-25-2013, 04:39 PM
Thanks for the neat info and nice images, Phil!

Kemalettin Sert
10-25-2013, 04:48 PM
6400 like 1600 on MX..almost no noise incredible

Phil Holland
10-25-2013, 05:03 PM
6400 like 1600 on MX..almost no noise incredible

I should say that these are straight h.264 exports from Redcine-X Pro. I have made DPX and encoded ProRes versions of these and I have to say, and we all know this, that there's a noticeable difference in quality.

At 4K under some lighting situations you might be able to get away with ISO 6400. Clip 3 in a less lossy codec looks actually tremendous at IS 12800, there's noise in the shadows, but it's really not crazy noise. Which is insanity.

Robert Ruffo New
10-25-2013, 05:39 PM
H264 hates subtle lower-luma gradients, but still, the lack of noise at highest ISOs is amazing. Really is a dream camera for those who, like me, sometimes shape the image with power windows and set-up shots with many layers of simultaneous action (often not possible to light all at the same level, especially if some layers are out a window, as even with all the watts in the world it wouldn't be comfortable for the actors). None of those layers will be compromised.

In 1080p (like I've said elsewhere 100% of our jobs are 2K or 1080p and there is zero indication that will change any time soon) noise looks fine until ISO 5000. With selective noise reduction, 5000 I would imagine would be pristine, especially if it were applied to the 6K original (i.e. before downscaling).

ISO 5000 at f1.2 gives you a bright image - maybe even moonlight will be usable as fill on some nights - certainly the light pollution within an urban area will read quite well. Time to buy more ND sheets for the lights....

Thank you so much for taking the time to do this.

Will Keir
10-25-2013, 07:36 PM
The final grade has so much "pop," it's really quite beautiful and shows the power of the correct tools in the correct hands. For a single BTS screen grab only a few words come to mind. Life and color, tone and grace, it's beautiful.

Can you go into greater detail as far as your color work to create the corrected image? Photoshop? Highlight and shadow isolation, image duplication similar to HDRx work? A dark image combined with a light?

Did you have HDRx enabled for this one?

Robert Ruffo New
10-26-2013, 02:40 PM
The final grade has so much "pop," it's really quite beautiful and shows the power of the correct tools in the correct hands. For a single BTS screen grab only a few words come to mind. Life and color, tone and grace, it's beautiful.

Can you go into greater detail as far as your color work to create the corrected image? Photoshop? Highlight and shadow isolation, image duplication similar to HDRx work? A dark image combined with a light?

Did you have HDRx enabled for this one?

I can answer one part: he didn't have HDRX enabled. Dragon has the latitude of MX + 'HDRX 3 stops', but all the time. without the need to involve HDRX, and without any of HDRX's caveats

Phil Holland
10-26-2013, 03:12 PM
The final grade has so much "pop," it's really quite beautiful and shows the power of the correct tools in the correct hands. For a single BTS screen grab only a few words come to mind. Life and color, tone and grace, it's beautiful.

Can you go into greater detail as far as your color work to create the corrected image? Photoshop? Highlight and shadow isolation, image duplication similar to HDRx work? A dark image combined with a light?

Did you have HDRx enabled for this one?


Robert's got it. No HDRx here. Very vanilla in terms of shooting this little piece. Straight camera and lens with the occasional use of an ND .9. Although, I'm real curious about just what's possible with use of HDRx and Dragon. I'd love to expose certain ways to potentially capture closer to 20-ish stops of dynamic range. You'd really only need that in real high contrast situations, but it's got me curious. I could see exposing wicked to the right and capturing more on the top end.

Will Keir
10-29-2013, 12:28 PM
Phil,

My question is more about your post work, very lovely. Did you take still and use photoshop to color grade or Resolve? Wondering what program and how meticulous the process was to get your final print. Simple curves vs, duplicated images with highlights/darks layered on top of each other. Or was this all done in RCX with a couple sliders?

Tutorial? :)




Robert's got it. No HDRx here. Very vanilla in terms of shooting this little piece. Straight camera and lens with the occasional use of an ND .9. Although, I'm real curious about just what's possible with use of HDRx and Dragon. I'd love to expose certain ways to potentially capture closer to 20-ish stops of dynamic range. You'd really only need that in real high contrast situations, but it's got me curious. I could see exposing wicked to the right and capturing more on the top end.

Will Keir
10-29-2013, 12:30 PM
WOAH! Moonlight fill... don't be ridiculous now Roberto!


maybe even moonlight will be usable as fill on some nights

Phil Holland
10-29-2013, 01:02 PM
Phil,

My question is more about your post work, very lovely. Did you take still and use photoshop to color grade or Resolve? Wondering what program and how meticulous the process was to get your final print. Simple curves vs, duplicated images with highlights/darks layered on top of each other. Or was this all done in RCX with a couple sliders?

Tutorial? :)

Tutorial, likely one day soon. A few folks have been after me to do a Resolve/Speedgrade/Redcine-X Pro/Baselight video. Color to me is much more than the program itself, but more about applying theory and using the tools to get there. Each are different, some are better at certain things, some I prefer to use because of how exactly they handle color itself. I do about 6-9 hours a semester at Gnomon on the subject and have been thinking about a way to piece together an entertaining video. I'll likely produce a video in the coming months before getting underway on a larger project next year.


The first "one light" grade shown in this thread:
http://www.reduser.net/forum/showthread.php?106511-Red-Dragon-It-s-Just-Paint
(http://www.reduser.net/forum/showthread.php?106511-Red-Dragon-It-s-Just-Paint)
Was a simple quick grade in Redcine-X Pro. Sort of earthy in many ways, but not much finesse really. FLUT adjustments, curves, you name it and it's probably in there. I was essentially stress testing the material.


The "final grade" shown here:
http://www.reduser.net/forum/showthread.php?107069-It-s-Just-Paint-Shot-on-Dragon-Final-Color-and-Finish

Was achieved in DaVinci Resolve and After Effects, I also did a few more experiments on top of that to really see what I could do with the material. Long and the short of it was the grade used secondaries, power windows, curves and sometimes in unorthodox ways towards the end of the piece mostly to attract the eye. I did a few larger pushes into stretching the workable latitude that I personally know falls apart on other cameras and formats.

I did specifically choose to shoot this piece under lighting conditions that would allow for a real stress test. That window and that shadowed balcony. Shooting into shadow, exposing it as a midtone or close to it, and using the dynamic range in post to add life back into what could have been blown highlights. There's little things you see in the fine details when projected like clumps of paint on the skin that really show how the REDCODE stands up too.

Will Keir
10-29-2013, 10:58 PM
Thanks Phil. I knew I saw your talent in that final image.

Robert Ruffo New
10-29-2013, 11:10 PM
WOAH! Moonlight fill... don't be ridiculous now Roberto!

A full moon is actually quite a few lumens - I'm not saying "fill" like for a face, but enough to get a dim but clearly legible read on a distant forest? Sure, at 5000 ISO that does in fact happen if the lens is fairly open, and again, if that moon is full and the sky is clear.

Will Keir
10-29-2013, 11:38 PM
When I get my Dragon upgrade, I'll be the first to try it coupled with 1.3T super speeds. I'm down for a little ridiculousness :) I can see a distance forest line visible, even working for some projects but the amount of noise isn't going to be pretty.


A full moon is actually quite a few lumens - I'm not saying "fill" like for a face, but enough to get a dim but clearly legible read on a distant forest? Sure, at 5000 ISO that does in fact happen if the lens is fairly open, and again, if that moon is full and the sky is clear.

Martin Stevens
10-30-2013, 02:23 PM
Awesome tests Phil!

Thanks.