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Dan Kanes
10-12-2016, 05:28 PM
Hi All,

Spent some time with the Epic-W Helium at Hot Rod Cameras today.

Got to play with Scott D's White Helium special edition a couple weeks ago.

At that time it seemed exactly the same (almost) between Dragon (LLO) and Helium(standard).

That was in controlled lighting.

Today in uncontrolled lighting I felt different results.

my preferred monitoring path today was actually Redcolor 4, Redgamma2

Not 100% sure on this yet... but gut feeling is this is a native 2000-3200ISO sensor when standard OLPf is in play.

Dyamic range is very good, at the same time my eye perceives more contrast in this sensor...I think it's natively more capable of picking up natural colors and casts... which can be good or bad depending on your goals for a scene.

I think the new color science will be better calibrated for this sensor, and soon hopefully.

Until then, I plan to be more cautious of my highlights even if the goalposts don't light up from clipping.

The sensor is capable of seeing things our eyes can't natively, and that is something to remember.

The film stock analogy 100% holds true here, spend time with your camera and sensor.

Long story short I would not feel shy setting camera to 2000 ISO outdoors and Nding, maybe 1600 in studio... might be able to get away with 800 at times.

At this time, I would plan on exposing to the right but not blindly, expose to the right and guard clipping. If you see something you don't like in the monitor highlight wise, stop down or ND, don't plan on recovering highlights to save a shot.

my favorite right now as of today: 3200 ISO, Redcolor4, Redgamma2 - 10/12/2016

Tylor Jones
10-12-2016, 05:33 PM
Good info, thanks Dan! Have you messed around with slow mo? 96fps at 5k? Curious how that looks

Dan Kanes
10-12-2016, 05:41 PM
In short slow mo looks gorgeous, just like we knew it would with all other Red cameras.

a key tool for understanding the new frame sizes is Phil's tool called Format Compare... too lazy to dig up a link at the moment.

Feature Request:

8K60P, 6K120P downsampled to 2K prores4444 (no r3d) in realtime... dunno if that's possible but would be nice.

Tylor Jones
10-12-2016, 05:44 PM
That was my biggest concern was when you get into 6k HD/5.5k HD, glad to hear it looks nice. Whew :)

Phil Holland
10-12-2016, 05:55 PM
In short slow mo looks gorgeous, just like we knew it would with all other Red cameras.

a key tool for understanding the new frame sizes is Phil's tool called Format Compare... too lazy to dig up a link at the moment.

Feature Request:

8K60P, 6K120P downsampled to 2K prores4444 (no r3d) in realtime... dunno if that's possible but would be nice.


PHFX | tools (http://phfx.com/tools/) is in my signature and I'm very glad it's helping. Working on some new more wordy stuff this month to help out on a few fronts too!

I have a theory about how REDCODE RAW encodes off of Helium, since the noise floor is so different I'm betting higher frame rates look rather banging.

ProRes 4444 is pretty chunky, but certainly something the engineers could look into if solo recording. Very curious what could be achieved when rolling an Intermediate Codec only for certain production workflows. Time will tell.

Tylor Jones
10-12-2016, 06:05 PM
Phil, thanks for all the tools on your website. Very much appreciated good sir!

Dan Kanes
10-12-2016, 06:15 PM
Counterpoint to not blowing your highlights - shadows hold a lot more detail than you may think with this sensor.

A. Clint Litton
10-12-2016, 09:44 PM
Dan, thanks so much for putting this impression into words. It's helpful to people who would like to start wrapping their heads around this new sensor but haven't had a hands-on experience yet.

Phil...man, thanks for all you do. Not sure how I missed this page of goodies, but Format Compare is something I was hoping was around. Not only is it handy for comparisons, but it's also so damn well done. Very much appreciated...

Dan Kanes
10-12-2016, 10:08 PM
Thanks Mr. Litton.

Oh One more thing - when in doubt, you can always view RAW on camera, and then use CameraRGB decoding in RCX along with Linear gamma... haven't brought files into RCX and done that yet, but did do some low level messing around with ETTR and Highlight protection concepts on a Laptop while on site.

My Epic-W should arrive tomorrow and will continue posting impressions.

Excited to try my Kipperties on this puppy, and I think the STH olpf might come in handy ;)

Nick Morrison
10-12-2016, 10:59 PM
Curious how 7K 10:1, 12:1 and 14:1 hold up at 800 iso.

Considering there should be almost NO NOISE...higher compressions like this may work pretty well...and could come in handy when file sizes need to be managed (for ex on doc shoots).

Stacey Spears
10-13-2016, 01:28 AM
Dan, if you like CameraRGB, then I suggest you take a look at RedWideGamutRGB.

Dan Kanes
10-13-2016, 07:17 AM
Thanks Stacey!

Gut feeling is that the current exposure tools (stoplights and goalposts) in camera don't really apply - except possibly under Raw. And that's only possibly... we're gonna need a bigger boat.

Dolph van Stapele
10-13-2016, 01:48 PM
Curious how 7K 10:1, 12:1 and 14:1 hold up at 800 iso.

Considering there should be almost NO NOISE...higher compressions like this may work pretty well...and could come in handy when file sizes need to be managed (for ex on doc shoots).

Nick, that is a good point. Curious about higher compression together with lower noise ratio on Helium.

Šabović Adis
10-13-2016, 02:59 PM
PHFX | tools (http://phfx.com/tools/) is in my signature and I'm very glad it's helping. Working on some new more wordy stuff this month to help out on a few fronts too!

I have a theory about how REDCODE RAW encodes off of Helium, since the noise floor is so different I'm betting higher frame rates look rather banging.

ProRes 4444 is pretty chunky, but certainly something the engineers could look into if solo recording. Very curious what could be achieved when rolling an Intermediate Codec only for certain production workflows. Time will tell.

To me it feels like truncated, think that more bits are needed? :biggrin:

Nick Morrison
10-13-2016, 07:18 PM
Nick, that is a good point. Curious about higher compression together with lower noise ratio on Helium.

Yup me too. We do lots of travel jobs and long interviews, and with most of our Media Management still happening on laptop setups to G-Tech drives, would to GREAT to figure out a ideal shooting compression/ratios on Helium.

Time will tell!

I also think Helium + Motion Mount could be killer. As shooting at 1280-2000 in Studio environments could be impractical (especially for highlights).

scott devitte
10-13-2016, 08:08 PM
Yup me too. We do lots of travel jobs and long interviews, and with most of our Media Management still happening on laptop setups to G-Tech drives, would to GREAT to figure out a ideal shooting compression/ratios on Helium.

Time will tell!

I also think Helium + Motion Mount could be killer. As shooting at 1280-2000 in Studio environments could be impractical (especially for highlights).

I have ef motion mount, next test lets see what gives.

Nick Morrison
10-13-2016, 08:16 PM
I have ef motion mount, next test lets see what gives.

Yup I have one too!

Dan Kanes
10-13-2016, 08:48 PM
Shooting off the cuff here...

I think optimal long recording format on Epic-W is 6KHD or 6K Open Gate. Optimal for Data, if you don't plan on reframing from 8K. save 8K for those beauty shots you used to shoot 6K for , and would shoot 5KHD or 4Khd to save space. Yes, it's more punched in, but that won't necessarily kill you unless you're trying to be close up with a wide angle lens.

Also, I think I'm going to Redact my suggestion of RedColor4 and Redgamma2... Possibly... Still not sure.

Thinking with Standard OLPF - rating sensor at 1600...

Quadruple check your Raw before you roll anything...

trying a fresh blackshade on the camera right now to see what that does.

Methinks there is some more calibration in the works... because of how this sensor Sees the world... it sees things we aren't used to seeing, so if you don't want to see those things, you have to plan for it.

Sorry if that's a bit coded...

Nick Morrison
10-13-2016, 08:57 PM
Shooting off the cuff here...

I think optimal long recording format on Epic-W is 6KHD or 6K Open Gate. Optimal for Data, if you don't plan on reframing from 8K. save 8K for those beauty shots you used to shoot 6K for , and would shoot 5KHD or 4Khd to save space. Yes, it's more punched in, but that won't necessarily kill you unless you're trying to be close up with a wide angle lens.

Also, I think I'm going to Redact my suggestion of RedColor4 and Redgamma2... Possibly... Still not sure.

Thinking with Standard OLPF - rating sensor at 1600...

Quadruple check your Raw before you roll anything...

trying a fresh blackshade on the camera right now to see what that does.

Methinks there is some more calibration in the works... because of how this sensor Sees the world... it sees things we aren't used to seeing, so if you don't want to see those things, you have to plan for it.

Sorry if that's a bit coded...

6K at what compression?

Problem with this is the FOV is equivalent to 4K on Dragon (ie Raven at 4KHD).

I'm in love with 5K Dragon for doc (Super 35), which would be 7K Helium (ie TWICE the data at same compression)...

Dan Kanes
10-13-2016, 08:59 PM
could go 6K at 8:1 to 10:1 with good results, but you could always go 5:1 and survive :)

Nick Morrison
10-13-2016, 09:02 PM
could go 6K at 8:1 to 10:1 with good results, but you could always go 5:1 and survive :)

Yeah with no noise, 10:1 could work.

More curious about 7KHD 12:1 though...as wouldn't be TOO much more data...and much better FOV...

Dan Kanes
10-13-2016, 09:19 PM
I'll try to whip off some tests tomorrow with 7KHD 12:1 for you.

Dan Kanes
10-13-2016, 11:11 PM
All about the RedWideGamutRGB + Proper White Balance + Log3G10 or Log3G12 + Curves... very clean and natural.

Dominik Bauch
10-13-2016, 11:29 PM
All about the RedWideGamutRGB + Proper White Balance + Log3G10 or Log3G12 + Curves... very clean and natural.

Got any images? Love to see some. How's the DR in your experience?

paulcurtis
10-14-2016, 04:06 AM
I think i good test would be demanding moving detailed footage shot at the same overall data rate 7K vs 5K Dragon, same FOV. To see if the theory of more res, more compression works. Especially if there is less noise.

Maybe we'd find that shooting 8K or 7K when it comes down to it, at the same overall data rate is comparable or better than the dragon equivalent. I have no idea.

Personally when i get mine my focus is on edges for green screen and keying work. I probably care more about that then most.

cheers
Paul

Dan Kanes
10-14-2016, 01:38 PM
Kinda busy prepping a shoot at the moment, but there may be a chance I could do some more intricate testing with shared results soon.

Dynamic Range is confusing... part of it is the Mapping of tones using Dragon or MX tone mapping.

This sensor seems to have a larger Gamut, and just sees a lot more latitude and color wise... at least that's my impression. Because it has higher native sensitivity you just need to watch clipping - if you aren't clipping in Raw, chances are you will be fine highlight wise.

Best Exposure practices feel different for sure, I would just plan on it clipping sooner in highlights since it's natively more sensitive. Whole scale moved up a couple notches...

Stephen Nguyen
10-14-2016, 02:46 PM
Thanks for your insight, Dan.

One of the most important factors for me to upgrade to Epic-W or stick with my Scarlet-W is whether the Helium sensor has less DR in the highlights than the Dragon sensor. DR in the highlights and roll-off are more important to me than cleaner shadows so I'm curious to see some comparisons between the two sensors to help me decide.

Adam Montville
10-14-2016, 02:55 PM
The Helium has "less" DR in the highlights is a misconception. It has less DR in the highlights at LOW ISOs. The base ISO is higher, and so the highlight protection starts at higher ISOs.

This is a Dragon chart, but imagine Helium, where the lower ISOs have even less highlight chips at low ISOs, and doesn't get coverage until you reach 1000+. It has the same amount of "chips" (16.5+ stops), but they shifted them.


http://www.artbyphil.com/phfx/cinematography/2015_REDWeaponCameraTest/bigs/phfx_REDWeaponTest2015_xyla21_ISOPatches_RLF.jpg

This is why having good NDs for Helium will be a must.

Thai Christen
10-14-2016, 03:20 PM
So, does anyone know what the base ISO for Helium is?

Based on my short tests so far, Helium clips sooner than Dragon (at ISO 800), using both standard OLPF.
Thus, I need to expose about 1-1.5 stop lower than I usually expose with Dragon at 800.
Does that make sense?

Brad Grimm
10-14-2016, 03:28 PM
So, does anyone know what the base ISO for Helium is?

Based on my short tests so far, Helium clips sooner than Dragon (at ISO 800), using both standard OLPF.
Thus, I need to expose about 1-1.5 stop lower than I usually expose with Dragon at 800.
Does that make sense?

With my limited testing, its looking like the base iso is 1600ish. Really amazing rich images coming off of this thing.

Phil Holland
10-14-2016, 03:42 PM
So, does anyone know what the base ISO for Helium is?

Based on my short tests so far, Helium clips sooner than Dragon (at ISO 800), using both standard OLPF.
Thus, I need to expose about 1-1.5 stop lower than I usually expose with Dragon at 800.
Does that make sense?

Give ISO 1280-1600 a try "generally speaking".

I've got to do a whole write-up tamale thingy on this shortly.

Thai Christen
10-14-2016, 03:50 PM
Give ISO 1280-1600 a try "generally speaking".

I've got to do a whole write-up tamale thingy on this shortly.

I have two shots at 1280 but still have the feeling Helium clips sooner. Will try with 1600-2000 tomorrow.
Looking forward to your write-up, Phil.

Dan Kanes
10-14-2016, 04:01 PM
I think it's about 2000 with standard OLPF.

Might be 1600 with SkinTone/Highlight OLPF.

Thai Christen
10-15-2016, 02:36 AM
Short test at 1600/2000 this morning. Now we are getting closer.
Very difficult scene with high contrast and very gentle nuances in mids to brighter tones (morning mist, forrest, clouds).

From what I can say with my limited knowledge, light roll off are gentle and beautiful, also transition. At least equal to Weapon Dragon.
However, Helium still tends to clip faster than Dragon so you really have to be careful on how you expose.
Will try with Highlight OLPF.

And yes, you need super strong ND filters if you want to open iris. Unfortunately my Tiffen variable ND vignette. So fix ND is the way to go.

scott devitte
10-15-2016, 06:18 AM
Going into this territory of using a lot of ND to shoot my Helium at a 1600-2000 base I.O. has exceeded the capability- (unless stacked with a non-variable, which I don't like doing, since my B&W circulars have a color cast that I don't want to compound) - of my variable NDs while shooting wide open on the 55mm, 1.7T Otus, which for me is the base standard lens for the Helium. I am very happy that I bought a fairly complete set of NISI NDs. I bought 2 NISI 4x4 polarizers as part of the group and am going to be experimenting on how they work together to make a variable ND. Does anybody know of a light weight clamp on 4x4, 2/3 stage with at least 1 rotating holder?

Kemalettin Sert
10-15-2016, 07:39 AM
Phil do a test against other cameras.Can you?

Daniel Soderberg
10-16-2016, 12:59 AM
Short test at 1600/2000 this morning. Now we are getting closer.
Very difficult scene with high contrast and very gentle nuances in mids to brighter tones (morning mist, forrest, clouds).

From what I can say with my limited knowledge, light roll off are gentle and beautiful, also transition. At least equal to Weapon Dragon.
However, Helium still tends to clip faster than Dragon so you really have to be careful on how you expose.
Will try with Highlight OLPF.

And yes, you need super strong ND filters if you want to open iris. Unfortunately my Tiffen variable ND vignette. So fix ND is the way to go.

Interesting... You feel the DR is a little lower on Helium than Dragon?

Thai Christen
10-16-2016, 01:19 AM
I can't say really because I normally don't do comparison tests etc. I let this to the others who have much better knowledge than I do.

However, having worked with a loaner Scarlet-W and rented Weapon CF in last couple of months, what I can tell is that I have to adjust on how I exposure with Epic-W. For the moment I expose somewhere around IRE 94 and below but definitely not more than 95. As soon as you go beyond IRE95, even there are no stop light in the histogram, when you open the file in RedCine it looks like highlights are "clipped". Yes you can retain all the details, they are there. But I prefer to have a "good and correct" exposure in camera.

Dan Kanes
10-16-2016, 10:54 AM
Funny Hack I've been using for exposure check... probably this is a horrible practice hence calling it a hack...

set 2000 ISO
Redcolor 4, Redgamma 2
Set FLUT anywhere from -1 to -2 (just for taste on set)

Set Iris based on RAW view so I'm not clipping anything I want to see.
Adjust flut level as necessary for on-screen image to look client acceptable prior to rolling.

Pleased with Results so far.

Nick Morrison
10-16-2016, 10:58 AM
Interesting... You feel the DR is a little lower on Helium than Dragon?

We compared Helium to Dragon at 800 ISO, and DR looked very similar.

However, considering Helium appears to be a 1600-2000 ISO camera, it may in fact have "more" DR at ths sweet spot (ie when you consider we monitored/exposed it perhaps a stop and a half "under" this at 800 ISO, and yet it still looked pretty much "the same").

So that...is promising.

I think the goal will be how to get Helium to work optimally at "studio" 800 ISO environments - perhaps Skintone OLPF? Internal ND? Mottion Mount?

Who knows.

Bear in mind we were monitoring with DRAGON COLOR...so until new color science is revealed...we really don't KNOW what we were looking at...

Kenneth C Merrill
10-16-2016, 11:06 AM
Set Iris based on RAW view so I'm not clipping anything I want to see.
Adjust flut level as necessary for on-screen image to look client acceptable prior to rolling.

Pleased with Results so far.

Post of the day. lol

Todd G. Peterson
11-01-2016, 08:53 PM
I'm still experimenting with ISO. My inclination is to leave it at the native 800. The operation guide suggests that you leave it at 800, then adjust aperture, lighting, filters, etc. then tweak within a stop or so of 800. But it sounds like 1600 might be closer to native?

If it's 1600, then it's quite sensitive and ND's will be my best friends. I don't shoot a lot outdoors, but part of the time. I was thinking of getting a new Schneider set. Would it be something like an ND9, ND12, and an ND15 as the core set?

Adam Montville
11-02-2016, 06:59 AM
At 1280, I'm getting amazing results. Even when lifting, once I export out of Resolve, the image looks so clean!

Also, I will have to do more extensive testing, but I noticed that I'm able to checkmark D.E.B. and me just playing with a few clips yesterday, zooming into 100%, it seems like it cleans up the noise even more! Anyone have any thoughts on using DEB on Helium?

Phil Holland
11-02-2016, 09:10 AM
At 1280, I'm getting amazing results. Even when lifting, once I export out of Resolve, the image looks so clean!

Also, I will have to do more extensive testing, but I noticed that I'm able to checkmark D.E.B. and me just playing with a few clips yesterday, zooming into 100%, it seems like it cleans up the noise even more! Anyone have any thoughts on using DEB on Helium?

DEB indeed appears to clean up chroma noise very, very quickly. Pros and cons to this, but if you're really stretching the limits it's there for sure.

Adam Montville
11-03-2016, 09:27 AM
DEB indeed appears to clean up chroma noise very, very quickly. Pros and cons to this, but if you're really stretching the limits it's there for sure.

Yeah, I did some further testing, and noticed when I enabled DEB, a green cast was put across the image, and almost like a "smoothing" effect on the noise in extreme ISOs (5000+), so I would base it on a shot by shot basis, but would recommend not to enable "Dragon enhanced blacks" on Helium.

Dan Kanes
01-28-2017, 12:19 AM
Forgot about this thread. Election and all that.

Coming back here... Still liking SkinTone highlight on Helium. RedWideGamutRGB + Log3G10 + IPP2 Preview Cube being my favorite onset monitoring workflow.

I did however decide to go with Standard for a VFx shoot running almost entirely at 120fps - glad I did that.

Using IPP2 Preview with Standard OLPF makes it totally acceptable and pleasing to my eye now.

If you're in a rough and ready mood and don't want to bother with IPP2 for now... simply RedGamma4 (or 2) + Dragoncolor 1 will allow you to have a passable monitoring path on set.

as noted in release notes - image quality on helium has taken a step up since IPP2 preview firmware.

One thing I'm having trouble with on my 6.3.73 IPP2 Preview beta is 2KHD being "screwed up" - emailed Red support to see if they have any remedies (probably a firmware update is in order - wondering if anyone is having trouble with 2KHD 240FPS on helium 6.3.75 release firmware.

Aaron Lochert
01-28-2017, 01:06 AM
Coming back here... Still liking SkinTone highlight on Helium.

That's what I've settled on as well. ISO 1280 and STH.

D. O'Bryan
01-28-2017, 04:43 PM
That's what I've settled on as well. ISO 1280 and STH.

In daylight conditions, studio, or is this what y'all are defaulting to in ALL settings? Cumulatively have rolled about 1.5mins since the camera arrived (expositing it as I would have the old scarlet) but hoping to do more testing over weekend.

Tom Gleeson
01-28-2017, 05:12 PM
At 1280, I'm getting amazing results.
Also, I will have to do more extensive testing, but I noticed that I'm able to checkmark D.E.B. and me just playing with a few clips yesterday, zooming into 100%, it seems like it cleans up the noise even more! Anyone have any thoughts on using DEB on Helium?

Are you using DEB on Dragon or Heluim footage? From what I understand DEB was designed specifically for Red channel noise we saw on the Dragon sensor but is Heluim footage benefiting as well? Yet to test DEB on Heluim as I have not had the need and I had assumed the Heluim would respond differently making DEB less ineffective.

D. O'Bryan
04-02-2017, 05:16 PM
Has anything changed now that IPP2 seems close to final? The new Helium ISO calibration and all....

STH + ISO 1280 still everyone's favorite? I'm loving how clip-resistant the camera is with those set, however there are times I feel like noise creeps into the midtones a lot earlier than I wish they would.

Josiah Duncan
04-02-2017, 08:47 PM
With the new noise calibration the equivalent to last week's 1280iso would be today's 640iso. For helium.

Aaron Lochert
04-03-2017, 12:17 AM
Has anything changed now that IPP2 seems close to final? The new Helium ISO calibration and all....

STH + ISO 1280 still everyone's favorite? I'm loving how clip-resistant the camera is with those set, however there are times I feel like noise creeps into the midtones a lot earlier than I wish they would.

Personally, with STH I was doing 1280 for highlight rolloff if there's a enough ambient light in the scene, or 640-800 for clean shadows. So with the re-calibration that's 640 for highlight protection and 320/400 for clean blacks. YMMV.

Martin Facci
04-03-2017, 01:30 AM
Are you using DEB on Dragon or Heluim footage? From what I understand DEB was designed specifically for Red channel noise we saw on the Dragon sensor but is Heluim footage benefiting as well? Yet to test DEB on Heluim as I have not had the need and I had assumed the Heluim would respond differently making DEB less ineffective.

That's correct but yes, it also cleans up very nice the chrome noise with the Helium sensor.

Aaron Lochert
04-03-2017, 02:45 PM
That's correct but yes, it also cleans up very nice the chrome noise with the Helium sensor.

I avoid DEB on Helium, it adds even more green to the shadows which I don't want.

D. O'Bryan
04-03-2017, 09:01 PM
With the new noise calibration the equivalent to last week's 1280iso would be today's 640iso. For helium.


Personally, with STH I was doing 1280 for highlight rolloff if there's a enough ambient light in the scene, or 640-800 for clean shadows. So with the re-calibration that's 640 for highlight protection and 320/400 for clean blacks. YMMV.

So wait, Helium just got less sensitive?

Shot all day ext's today at 1280, STD olpf, ƒ4 and some ND and it seemed great in the histogram with the new calibration. Only rolled 2k ProRes so I'm really hoping I didn't screw it up :/

Kenneth C Merrill
04-03-2017, 09:08 PM
It was "less" sensitive to begin with. They just finally got the ISO labels "right" (i.e. closer to everyone else's).

Aaron Lochert
04-03-2017, 09:10 PM
So wait, Helium just got less sensitive?

Shot all day ext's today at 1280, STD olpf, ƒ4 and some ND and it seemed great in the histogram with the new calibration. Only rolled 2k ProRes so I'm really hoping I didn't screw it up :/

ISO on RED is just a number at the end of the day. Nothing changed to the sensitivity. But all ISO's now look one stop brighter than they did before. Meaning yesterday's 800 looks exactly the same as today's 400.

By shooting ISO 1280 with the new calibration, you basically shot ISO 2500 on the old calibration. Which means you gave yourself a LOT of highlight protection at the expense of noise. But for a 2K delivery, I'm willing to bet it still looks incredible. Especially since you said they were exteriors.

Edit: Just reread and saw you recorded ProRes, so that is more than "just a number" since you're baking it in.

Dan Kanes
04-03-2017, 10:59 PM
I'll post my updated practices after testing the new FW.

I found that with IPP2 preview and a skintone highlight OLPF I could rate 800-1600 in daylight and be happy.

Excited to test the new sauce out.

Aharon Rothschild
04-04-2017, 06:19 AM
It would really help DP's who are renting the camera and recording pro-res to get a straight answer on native ISO (ie. wherever the stops over and under line up) and to how many stops of over exposure are available at that ISO in a real, on set, way. Not in theory as in counting stops at iso 3200 in the noise floor but in a concrete way that corresponds to a light meter.

D. O'Bryan
04-04-2017, 11:40 AM
ISO on RED is just a number at the end of the day. Nothing changed to the sensitivity. But all ISO's now look one stop brighter than they did before. Meaning yesterday's 800 looks exactly the same as today's 400.

By shooting ISO 1280 with the new calibration, you basically shot ISO 2500 on the old calibration. Which means you gave yourself a LOT of highlight protection at the expense of noise. But for a 2K delivery, I'm willing to bet it still looks incredible. Especially since you said they were exteriors.

Edit: Just reread and saw you recorded ProRes, so that is more than "just a number" since you're baking it in.

Got it! So to recap 640 looks/is mapped to result in the same levels as 1280 did last week?

I'm very happy with the results so far in my 2k ProRes files. You're right, I had gobs of highlights to work with and no noteworthy noise in the shadows (I think we have the crazy oversampling to thank for that).


It would really help DP's who are renting the camera and recording pro-res to get a straight answer on native ISO (ie. wherever the stops over and under line up) and to how many stops of over exposure are available at that ISO in a real, on set, way. Not in theory as in counting stops at iso 3200 in the noise floor but in a concrete way that corresponds to a light meter.

This. I totally understand how the RAW processing works and that ISO is just a number, but now that these cameras can write baked-in files it would be great to get a published "This ISO = this many stops over/under" chart from RED.

Aaron Lochert
04-04-2017, 02:12 PM
Got it! So to recap 640 looks/is mapped to result in the same levels as 1280 did last week?

Exactly. All that's changed is the mapping, nothing at the sensor level. If you remember that test between Alexa and Epic-W that was so contentious on NoFilmSchool, the DP put both cameras at 800 for "fairness" but it actually wasn't fair. Conveniently, with this new ISO recalibration, setting both to 800 now puts them on a a more even playing field.


This. I totally understand how the RAW processing works and that ISO is just a number, but now that these cameras can write baked-in files it would be great to get a published "This ISO = this many stops over/under" chart from RED.

I shot a short clip right before and after the new firmware and could confirm that the old one 1280 looked exactly like the new one at 640. Assuming there's no other trickery going on that I just couldn't see, I'd think it's safe to say that Phil's testing is still relevant, just divide every ISO number by 2:

http://phfx.com/phfx/cinematography/2017_REDSensorTest/bigs/phfx_2017_RED8KSensorTest_REDHeliumDragon_ISONotes .jpg

Aharon Rothschild
04-06-2017, 05:46 AM
Ideally ISO on camera should match to your light meter and allow for even over and under exposure with a acceptable noise floor.
I would recommend shooting a exposure test similar to Geoff Boyle's work. Set base to T8 and open and close the lens. Include a actor and a chart with a greyscale. Bring the reaults into resolve. See where middle grey lands in IRE relative to what was metered. See where the stairstep from the greyscale chart distributes evenly above and below middle grey. That's your base ISO. Count how many stops over to clipping on skin. That's your over exposure range. Count how many stops under untill noisy on skin. That's your under exposure range.

This allows the light meter to become a far more useful tool than the histogram as we can dial in a tight ratio on our actors skin on set and we can let our gaffer do the work.