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Opinion POLL: EPIC native ISO = 800 or ISO = 320?

Opinion POLL: EPIC native ISO = 800 or ISO = 320?


  • Total voters
    159
I guess it all boils down to the definition of the word "native." What is it?

If GN is calling "native" the suggested starting point because its gives an pretty good range of highlights and shadow details, then it's not really a technical definition. But it supports why people use ISO800.

If others are calling "native" the ISO the point at which they "visually see" the same exposure when switching to the RAW view, then it's more technical of a definition. And it supports why people "say" ISO320 is native but some still shoot the camera at ISO800 on most occasions.

I don't know why it all matters, anyway. As a rule of thumb, I've always shot ISO800, ETTR, then picked up shadow details in RCX by sliding back to ISO320. It has worked well enough to produce nicely exposed, clean images. I'm afraid that if I set the camera to ISO320 and exposure for that, I have less latitude in post. This is not scientific, just based on trials and errors. In the end it gets me where I want to be.
 
So the one thing that all must agree on based on Graeme's comments are that 100% of the people in the poll are wrong. Including me. But hey we got an answer. Native doesn't exist.
 
I guess it all boils down to the definition of the word "native." What is it?

If GN is calling "native" the suggested starting point because its gives an pretty good range of highlights and shadow details, then it's not really a technical definition. But it supports why people use ISO800.

If others are calling "native" the ISO the point at which they "visually see" the same exposure when switching to the RAW view, then it's more technical of a definition. And it supports why people "say" ISO320 is native but some still shoot the camera at ISO800 on most occasions.

I don't know why it all matters, anyway. As a rule of thumb, I've always shot ISO800, ETTR, then picked up shadow details in RCX by sliding back to ISO320. It has worked well enough to produce nicely exposed, clean images. I'm afraid that if I set the camera to ISO320 and exposure for that, I have less latitude in post. This is not scientific, just based on trials and errors. In the end it gets me where I want to be.


What is "native" indeed. I don't really think the RED cameras have a "native" ISO, but they do have a range of good ISOs you can use, all with the same dynamic range. Basing "native" off the raw view is incorrect because the raw view is just a "raw-ish" view designed to show what people wanted from a raw view - a locked-off image with all the highlight detail there.

You know, sometimes it's "whatever works to get the image" and there's many different ways to get to a superb image.

Graeme
 
You have to have a starting point to expose the image regardless of whatever post effects and tricks you can apply to the image after capturing it.
If the image you capture is incorrectly exposed then you're off to a bad start in the quest for making great looking images.
The camera sensor or film stock you're using has to have a base point, a "native" ISO/ASA on which you dial in your exposure settings on location by either moving the F stop or adding ND.

This thread goes around in circles because of the science behind the process but at the end of the day you're shooting with a camera sensor that has a "native" rating that needs ND to be used at lower F stops to get the properly exposed image with the desired DOF.

This thread is a clear example why people choice to shoot on a different camera that isn't lost in its own technology, running around in circles trying to explain the science behind the art.

I'm still confused as I'm sure many others are... What is this camera, which is a tool used to capture light, rated at? 320 or 800

Why make it so confusing?
 
I don't think the technical issues are confusing at all....but, yes, I can see why it can be confusing.

I come from a film background and strangely I think that helps.

If the Epic MX had over 20 stops of Dynamic Range and was visually noiseless, and the scene before
you had only 10 stops of DR, then the whole Native ISO thing would be all over the place. In other words.
the more DR a sensor has the more variable is its ISO capability.
 
This thread is a clear example why people choice to shoot on a different camera that isn't lost in its own technology, running around in circles trying to explain the science behind the art.

I'm still confused as I'm sure many others are... What is this camera, which is a tool used to capture light, rated at? 320 or 800

I don't know how much simpler it could be. Red says 800. So 800 it is. Done and Done. It's not rocket surgery. There are all kinds of tools built into the camera to help you. I think a lot of people just don't understand how it works. Those people still don't understand how it works on an Alexa. When shooting film, people push, pull and flash to no end to get a look they are after. All an EI or ISO, or ASA, or DIN, if you wanna go there, is is a starting place. I am really baffled as to how anyone can have an issue with this, unless they don't understand basic photography.

Nick
 
if its so basic then why do some many people have conflicting opinions on the "native" ISO/ASA of the camera?

Wouldn't it be easier and benefit everyone to have a true reading of the sensor and know if you change the ISO/ASA then you're moving away and adding a process.

Doesn't the R3D default to 320 when you work in RedLogFilm?
Sure I can change the settings just like I can manipulate the image in post but it doesn't help much on-set in the elements judging the available light and acting accordingly.

So what is it? 320 or 800?
Judging from this poll is leaning more towards 320 yet still people are insisting on 800.

Pretty crazy that there is such a great contradiction to what effectively is the most important spec to know when you're capturing light.
 
Yes, some cameras will, even in RAW, bake in digital gain as well as analogue gain (which you expect to get baked in). As Blair notes it doesn't stop the signal being linear, but it does diminish the highlight ability (or if negative gain is baked in) data precision.

Graeme

I know I've gone on about this too many times before but would it not be beneficial for epic to have an option to bake in the gain too? Lots of people are noticing that a signal recorded live out of the hdmi is cleaner than an r3d at high iso's. Isn't this because in that situation an external recorder is compessing the boosted image (like a regular RGB camera), which is the reverse to the way epic records. Always recording a 320 ish image and applying gain later is surely going to introduce more artefacts when you boost to say 2000iso for grading.

I'd love an option for epic to compress the user histogram I'm looking at so it's not wasting space compressing highlights that arnt there, and can throw that information away.

A feature like this would be great for low light. Or am I talking rot?
 
All I know is: with digital, it is pretty difficult to get good shadow detail, that's the biggest drawback of digital vs film. So, the way I compensate for that is effectively crank up all my highlights without clipping, this forces details to emerge from the shadows, then slide back to ISO320 in RCX for a well balanced shot that can compete with film (somewhat). So, in a sense, I am shooting in ISO800 but exposing for ISO320 (via over-exposing without clipping). Does that mean "native" is 320 or 800? I don't know.

If you have a methodology that works, then really its not that confusing. Just spend time with the camera, do trials and errors, and figure out what works. It's a tool, RED has designed it and gave us more options to work with, now it's up to me to learn it and find my "way" with it.
 
if its so basic then why do some many people have conflicting opinions on the "native" ISO/ASA of the camera?

Wouldn't it be easier and benefit everyone to have a true reading of the sensor and know if you change the ISO/ASA then you're moving away and adding a process.

Doesn't the R3D default to 320 when you work in RedLogFilm?
Sure I can change the settings just like I can manipulate the image in post but it doesn't help much on-set in the elements judging the available light and acting accordingly.

So what is it? 320 or 800?
Judging from this poll is leaning more towards 320 yet still people are insisting on 800.

Pretty crazy that there is such a great contradiction to what effectively is the most important spec to know when you're capturing light.

The thing is as Graeme said...
The ISO standard states that it is up to the manufacturer to rate a RAW camera....red has stated 800...so according to ISO thats what it is, no amount of voting can change that....
Whether you shoot at that or at 320 is a personnel choice....
When the standards organization basically says there is no standard for RAW cameras....then all the rest is marketing, and subjective.

Like was said before SNR is more of a science....
Even dynamic range can be subjective to useable range
 
"Judging from this poll is leaning more towards 320 yet still people are insisting on 800." - problem is that the people who insist on a) stating there's a native ISO when there really isn't, and b) that it's 320 are not the people who designed the camera. If there was a nice simple happy answer I'd give it to you, but there's not because the camera is happy working over a wide range of ISOs, all of which have the very same dynamic range, all of which suit different scenes better than others due to a different distribution of highlight and shadows range around mid grey. The manufacturer recommends you start with ISO800 for a reason, and that is we've practically found it a very good place to start.

Graeme
 
I think marking has a play here as 800 certainly sounds better than 320 but it seems in reality based on what people are seeing using the camera going off this poll which is a small slice of the users out there... the Epic sensor is 320 and with post effects can be 800 if you want it to be.

But ultimately (A) on a hot sunny day outside its a 320 sensor so ND up and (B) on a dark moody night its a 320 sensor so add lighting and open up the aperture.

Take A or B and fiddle in post until the cows come home.
 
But surely even if the camera and post software can happily work with different ISO settings the amount of light being captured by the sensor will remain the same amount of light being captured by the sensor and the only things that will effect the light captured by the sensor would be Aperture and Filters in front of the lens.
 
But surely even if the camera and post software can happily work with different ISO settings the amount of light being captured by the sensor will remain the same amount of light being captured by the sensor and the only things that will effect the light captured by the sensor would be Aperture and Filters in front of the lens.

Yes, that is correct, which is why the ISO recommend on a RAW camera the manufacturer decide on the ISO, which we have, and that's where the 800ISO comes from as a practical recommendation. I really don't like to say people are wrong, but I don't think you're right by stating it's a 320 sensor, not least as that meaningless as a raw image doesn't have an ISO sensitivity the way film does because the development curve is very flexible and you get valid developments over a very wide range, and none delivers more or less dynamic range than the others. If we have a variable analogue gain stage some gains would deliver more DR than others and you could call the one or ones that deliver the most "native", but really, the concept of "native" doesn't really make much sense here.

Graeme
 
Thanks Graeme. I'll go back to my initial statement of, "it doesn't matter what the native iso of the sensor is." what matters is exposure.

Agreed Bob.

Graeme
 
To a DP who wants to expose the image correctly knowing the "native" sensitivity of the sensor or film stock is crucial to either closing or opening the F stop on the lens or removing / placing ND in front of the lens.

If Red are saying to rate the sensor at 800 to force the use of ND or Stopping down when the actual raw sensor is 320 (defaulted to 320 when using RedLogFilm) isn't that just a trick to protect the highlights and get a more film like response to the bright roll off on a digital sensor.

To me this all seems gear towards protecting the highlights as the camera software in Redcode and in post debayer all work better at less noise and better shadows and its the highlights that the Red sensor has problems with.

So the sensor is really 320 but because of software advancements if you work at 800 you'll have more protection in the highlights.
 
AFAIK there's no defaulting to 320 for RLF. I'm not sure where you're getting that from. As for the rest, go back and read my comments in this thready.

What you're saying about the sensor is not how sensors work. Sensors don't have an ISO rating. Sensors are not film. Sensor data + development curve produces an image, and we have a digital equivalent of ISO that is valid over a range of values. Think, like Gunleik suggests above that each one of those ISOs is a different stock with different capabilities if you want.

Graeme
 
hasn't it always been about exposure?
and isn't exposure reliant of the sensitivity of the sensor or film stock?

Its all well and good to exposure something you can see and change on the fly as you are viewing it but what when you have to expose for an event that is about to happen, say an explosion... you need to know before hand what you are working with and set up your camera, lens and filters before the event and the event is over before you know it.

Knowing that you are dealing with 100 ASA film stock you can setup your exposure accordingly. But effectually what you are saying is the EPIC is between 320 and 800... that quite the contrast between the two and it introduces quite the wild card to expose for... which do you choose 320 or 800? Do you ND up or leave it clean? Suddenly you're in the unknown as its hard to make a decision when the goal post can't make up their mind.
 
When working with RedLogFilm in Flame it defaults to 320 and a few people on this thread an other threads have confirmed that 320 corresponds with the Raw image.

Its fantastic to have many "film stocks" to choose from and sometimes its confusing to which "film stock" you are really exposing for.
 
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