ISO of Red

[Florian Stadler]

Just to throw a little curve into the discussion: ETTR instead of consistent exposure is all well and good to minimize noise on an individual shot basis. I am a big believer in consistent footage and consistent noise levels in a cut sequence. Pick your noise level and stick to it through the sequence if not the whole act. Changing noise levels takes the viewers out of the film watching experience by making them aware of the film making process whereas a consistent level will get them acquainted within the first five minutes. From that consistency one can take departures according to the story and of course find a separate level for day/ext, day/int, night/ext, night/int

 

[Zakaree Sandberg]

Shooting ISO 160 is a mistake with RED, except in exceptional circumstances.

I would never set my cameras ISO to anything BUT 320, Because that seems to be the standard set by RED..
I would however set my meter to 160 to 200 in order to expose for the cameras 320.

My thought was that the camera says 320... but that 320 is really 160

NO?

 

[Ryan E. Walters]

Just to throw a little curve into the discussion: ETTR instead of consistent exposure is all well and good to minimize noise on an individual shot basis. I am a big believer in consistent footage and consistent noise levels in a cut sequence. Pick your noise level and stick to it through the sequence if not the whole act. Changing noise levels take the viewer out of the film watching experience by making them aware of the film making process whereas a consistent level will get them acquainted within the first five minutes. From that consistency one can take departures according to the story and of course find a separate level for day/ext, day/int, night/ext, night/int

Good point, and thanks for bringing that up- consistent exposure is a must. Which is another reason why a meter is so important to me- I can double check light levels and know that I'm getting the correct stop.

 

[Sanjin Jukic]

Yesterday we knew nothing. Today we know something. Tomorrow we just might be dangerous.

Jim

Jim,

it's a very nice credo...

But in between I would like also to suggest that finally shot on RED web page "http://www.red.com/shot_on_red/"

put on there Lars von Trier's movie "Antichrist" (the movie that like it or not doesn't matter in this case) shot mostly on RED1 by

Anthony Dod Mantle, BSC, DFF,

Cinematographer, the ASC and Academy Award® Winner,...

A lot of people think that this is one of the best movies shot on RED1 till today.

Also I think that Anthony Dod Mantle, BSC, DFF, just "nailed" the best points shooting with RED1 and that should also somehow respected by RED comapany.

BTW, also further Anthony Dod Mantle, BSC, DFF, as a great cinematographer, the ASC and Academy Award® Winner should be ALSO consulted in

any future RED camera development like an Epic, Scarlet,... because he is really the best experienced and knowledgeable guy for that job.

Jim, again it's just all about for your consideration...

 

[Cail Young]

My thought was that the camera says 320... but that 320 is really 160

It is scene dependent. If you don't have bright objects above skintone, sure, expose at 160. However if you are outdoors, or want skintones lower than a stop or two than the brightest objects in the scene (for some reason) then 160 will not be good for you.

 

[Jannard]

People are trying to put 18% grey on RAW instead of post. I would re-think that.

Jim

 

[Ryan E. Walters]

People are trying to put 18% grey on RAW instead of post. I would re-think that.

Jim

So then why don't you, or someone at Red enlighten us rather then only post cryptic messages? (This is an honest statement, and not meant to be disrespectful- honestly- enlighten me.)

Exposing the image is the most important part of the image making process in Digital - IMO. But it is one of the last set of choices that gets made on during production. I need a way to determine what kind of lighting package I need for the project I am working on. I need a way to communicate effectively and precisely to my lighting crew. I need a way to make sure that the lighting is consistent between setups. And I need a way to gather important lighting information when location scouting. All this comes before the final exposure is made, and for me it is the point of trying to figure these things out. So that I can be as prepared to make the best image possible with the Red.

So, IF meters and rating the camera is useless for use with the Red, how are the above issues resolved? (I do not believe this to be the case- I still see meters to be a very important part of the process, but I'm prepared to be wrong on that ...)

 

[CJ Roy]

Setting meters @ 320 while the camera is also at 320, and lighting to that, will produce underexposed images on set. Boosting the levels, raising the curve in post to approx 320 could, and most likely will, raise the noise floor to an unpleasing level. There are very few producers, clients and agencies that would not raise a stink about an image looking too dark.

I don't understand why RED is suggesting this, as if it's all for highlight protection? I can keep track of blown out highlights a lot easier than I can the noise floor.

 

[Jannard]

Sorry for the cryptic message. We recognize that a few are getting lost in exposure and are working hard to come up with a simple plan with Graeme's new color science. Give us just a bit and we will have a simple solution to all this.

Jim

 

[CJ Roy]

Sorry for the cryptic message. We recognize that a few are getting lost in exposure and are working hard to come up with a simple plan with Graeme's new color science. Give us just a bit and we will have a simple solution to all this.

Jim-

The 30 or so DP's I've worked with in the past two years, ALL rate the camera around 160-200. It's been this way since day one. It's really not a few, it's a lot.

-CJ

 

[Shawn Nelson]

People are trying to put 18% grey on RAW instead of post. I would re-think that.

Jim

As David Mullen said, that's because the Redspace false color tell us to do so.

I wonder if the false color exposure could be dynamic in that after reading the scene (detecting the DR) it could place 18% and skintone accordingly?

Everyone keeps saying ISO 160 on the meter, and you and Graeme keep saying things about protecting the highlights, well thats only in outdoors or extremely high DR situations. I've done a number of productions and observed a ton of productions that were shot entirely under artificial light (not hard to do, many interiors are) or outside where the sky wasnt that bright. In those situations where you can control your highlights, it seems that the lighting meter should still be set to iso 160 to get the cleanest image possible. I can light a scene using a meter at iso 160 without clipping anything and it yields a nice fat waveform.

It's interesting that this thread of mine has over 5000 hits (pretty big for a non Recon thread). Seems a lot of us are at the point where we're trying to get the most out of the image. Even the ASC (...). So I am glad to see that you guys are treating this seriously to make it easier, since very intelligent people who are trying very hard keep screwing it up.

I take it as a good sign of the maturing community that we're on to dealing with precision of this nature.

 

[Bob Torrance]

People are trying to put 18% grey on RAW instead of post. I would re-think that.

Jim

I'm sure I missed something, but isn't the RAW signal what the sensor is actually seeing (the negative so to speak)? Wouldn't doing it in post be kind of like letting the lab print for 18% grey?
Maybe I better just have a drink.

Bob Torrance

 

[Ryan E. Walters]

Sorry for the cryptic message. We recognize that a few are getting lost in exposure and are working hard to come up with a simple plan with Graeme's new color science. Give us just a bit and we will have a simple solution to all this.

Jim

Thanks. I am looking forward to the new FLUT and the new sensor. I can't wait until it gets here. (And I am sure that you cannot either.) But I am looking for a solution with the current camera, as that is the tool I have at hand. (Or is the FLUT going to be added to a new camera build?)

 

[Ryan E. Walters]

I'm sure I missed something, but isn't the RAW signal what the sensor is actually seeing (the negative so to speak)?

That is my understanding of the system. And as I have understood it, as with DSLR's it is best to shoot for the RAW, and then develop for the JPG. Or in RED's case- shoot for the RAW and then develop for Rec709, film, etc.

 

[Kim Frank]

People are trying to put 18% grey on RAW instead of post. I would re-think that.

Jim

Sorry...
I do understand everything that has been said in this thread, except for this post. According to what you are saying Jim I should protect the highlights as much as I can, by taking the highest ISO my taste of noise can accept and then raise the mid grey in post. But if I underexposed mid grey in the first step by gaining a higher ISO this will bring up my noise floor.
Also I don't like the look of raising the midtones in post too far and softening the S curve or knee roll off with that.
I really don't understand and I thought I would. Now Im confused again.

 

[Lauri Kettunen]

But if I underexposed mid grey in the first step

Kim, the issue is, there is no mid-grays on the raw signal. This is because the signal is directly proportional to the amount of light, whereas our eyes do not react on light in this way. Thus the need for the gamma curve.

Still, it seems that during shooting many want to subconsiously anticipate where the mid grays are going to be in post. Consequently they shoot with a style that emulates the characteristics of film with the digital camera. In the past this style was justified and a necessity because the gamma curve was more or less built into the film. Or more precisely, film is not linear implying you can't manipulate light in "post" as if you were adjusting the iris in "pre" stage. In case of CMOS sensor you can in (one sense) manipulate light in post as if you were just adjusting the iris. That's what linearity means. Guess this also creates the confusion.

In the past one needed an external light meter because there was no other way to know what the "film is seeing" grainwise. But, in case of Red One that's what the camera meters basically tell precisely; The camera can tell what "the sensor is seeing" pixelwise, and so in this sense there is no need/use for external light meter.

 

[Sanjin Jukic]

Kim, the issue is, there is no mid-grays on the raw signal. This is because the signal is directly proportional to the amount of light, whereas our eyes do not react on light in this way. Thus the need for the gamma curve.

Still, it seems that during shooting many want to subconsiously anticipate where the mid grays are going to be in post. Consequently they shoot with a style that emulates the characteristics of film with the digital camera. In the past this style was justified and a necessity because the gamma curve was more or less built into the film. Or more precisely, film is not linear implying you can't manipulate light in "post" as if you were adjusting the iris in "pre" stage. In case of CMOS sensor you can in (one sense) manipulate light in post as if you were just adjusting the iris. That's what linearity means. Guess this also creates the confusion.

In the past one needed an external light meter because there was no other way to know what the "film is seeing" grainwise. But, in case of Red One that's what the camera meters basically tell precisely; The camera can tell what "the sensor is seeing" pixelwise, and so in this sense there is no need/use for external light meter.

Lauri,

thanks and I would say you've made good points...

 

[Steve G]

The camera can tell what "the sensor is seeing" pixelwise, and so in this sense there is no need/use for external light meter.

Actually, light meters are still needed. Gaffers use them to pre light sets. They are good for lighting ratios. Sometimes you don't want to go back to the camera every time you want to see what the light is doing in terms of exposure.

 

[Rich Schaefer]

Me, I put my Red cameras at 320 and my lightmeter at 200 or 160 and everything works out!

When I shoot film I expose with a lightmeter. When I shoot digital or video I expose with the appropriate meters, RAW histo or wave-form.

For all formats, I do use my lightmeter to pre-light upcoming sets with my lighting crews. For Red we set the meters at 160.

 

[Eric Haase]

Setting meters @ 320 while the camera is also at 320, and lighting to that, will produce underexposed images on set. Boosting the levels, raising the curve in post to approx 320 could, and most likely will, raise the noise floor to an unpleasing level. There are very few producers, clients and agencies that would not raise a stink about an image looking too dark.

CJ hits on a good point here. Assuming for a moment that the noise level will be acceptable I think it's important that the image on the monitors look close to what they will after processing. It's impossible to explain to a client/agency/director that even though the actors faces look exceptionally dark everything will be fine.

If there were a way of having a bit more control over custom curves in the camera to get the image to look like the intended result after post it would be ideal. I would like to see a few more points on the curve as well, instead of just the 5. The interface for setting the curve in camera should be intuitive and fast to use. Currently it is cumbersome to dial a curve in with the LOOK settings. Maybe utilizing a GUI curve with the new touchscreens would work? There could also be some presets that boost a certain IRE range by a preset amount. We can also currently dial in settings in Rocketcine or RedAlert and program those numbers directly in to the camera but this is too time consuming for practical purposes most of the time. Having those settings updated in realtime wirelessly from the computer to the camera would be ideal. Imagine sitting at the DIT station with a live image coming HD SDI from the camera, tweaking settings in REDALERT/ROCKETCINE and having those update realtime wirelessly in the camera and monitor feed? You could dial in your custom curve very quickly.