Dragon Noise Confirmation

[Paulo Emílio]

Neat video, is cheap and works great.

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[Hrvoje Simic]

When doing noise tests I propose considering motion imagery.

Noise is dynamic and its final appearance cannot be perceived realistically with photographic approach alone.
It can look less or more noticeable in motion.

Dragon has so much latitude that you can pretty much see a white frame on the screen and it will look great when pushed down in post.

Although the material from this sensor has gains this statement is very general and it is advisable that it is perceived with caution.

Relying on this notion tends to lead to dependence on post to get a usable image after sloppy exposure on set. Missing optimal exposure leads to offsets in color rendition, local contrast, density distribution and texture characteristics and if missed beyond certain point noticeable inconsistencies between optimally and incorrectly exposed shots edited together.

 

[David Battistella]

Or you could process it around 400ISO?

 

[Mark L. Pederson]

Just based on my Epic experience from the last couple of years, this seems a little noisy for ISO 800. What do you guys think?

Looking at the frame rated at ISO 800 - it's clear from the histogram that you could have opened your iris another TWO full stops - dramatically reducing noise. Unless you were shooting wide open - or you were choosing that aperture setting for creative depth of field - you would have gotten a cleaner image by getting more light to the sensor.

Noise is directly related to how much light you get to the sensor - not to your choice of ISO rating. (although - your choice of ISO effects your histogram and your CHOICE of aperture)

I think this exposure if fine - but if you wanted a cleaner image - open up that iris or add more light - you had a solid two more stops available on this image without clipping the subject - as demonstrated when you boost this image 2 stops in RCX.

 

[Mark L. Pederson]

Or you could process it around 400ISO?

If you change the ISO rating in post processing and then lift the image with curves, etc. - you will not reduce the noise. Very clear from the histo at 800 - there was a lot of room on the right - a solid 2 more stops. So opening up one stop or ideally two - would have been the best approach for cleaner image IMO. It's not a deep focus shot either - so assuming this wasn't shot wide open - I suspect the creative intent would be maintained with just a little more love on the iris.

Alternatively - if he would have RATED camera at ISO 400 - and exposed with the exact same histo on the camera - he would have been forced to open up one full stop - and had a cleaner image

 

[David Battistella]

Hence, rate lower indoors and rate higher outdoors and have one rating for the in betweens.

People seem to think it's the opposite, like crank the ISO when I don't have enough light. That's bad strategy.

This is an exposure range strategy. When you are I low light it's better to rate lower, open up or add more light as the noise tends to come through pixels that have been light starved.

There were two full stops to push light onto the sensor and in the process end up with "cleaner shots".

you can always leave the camera at 1 rating and control the light with iris and nd based on a lower noise rating and give yourself some room in the highlights. (Effectively moving middle grey without moving your rating) but moving it with your exposure.

battistella

 

[David Battistella]

Also,

color fidelity is slightly different at lower ISO's when post processing. If I went for the same "levels" at 800 ISO there would be a slight color shift that goes with that so one needs to be wary of color considerations when switching post ISO development. Not all ISO development is exactly the same color.

Battistella

 

[Elsie N]

Also,

color fidelity is slightly different at lower ISO's when post processing. If I went for the same "levels" at 800 ISO there would be a slight color shift that goes with that so one needs to be wary of color considerations when switching post ISO development. Not all ISO development is exactly the same color.

Battistella

David, Mark, anyone who has checked for this... does the "range" of the Dragon sensor translate to post? That is does the color shift you mention in post stay true to what the sensor sees as middle gray shifts when setting up shots? Furthermore, is there much of a color shift between the lower end of the range and the higher end?

 

[Mark L. Pederson]

Furthermore, is there much of a color shift between the lower end of the range and the higher end?

No there is not.

 

[David Battistella]

is there much of a color shift between the lower end of the range and the higher end?

It's not a massive color shift, it's slight. Dragons color fidelity is pretty amazing through all ranges. It's a tough call. These sensors are all about 5000K, so they will look sharpest when lit with Daylight sources and slightly softer with tungsten sources. So when you are in a living room with available mixed light sources and you underexpose, you are going to maybe get hit with a bit more noise, which translates to slightly softer image.

Just try it yourself. Download the R3D and process the shot at 2000 ISO using curves and the scopes. Save the preset. Now process it gain at 400 using curves and the scope and "match" them. Theoretically they should be equal but any kind of gain you add to an image can affects it's color/noise performance. Now, if you paste between the looks, you might see ever so slight shifts in color depth and tone. Curves are one kind of gain, ISO is another kind of gain.

IN the end, it's the look you prefer. If you did it with well lit charts you might also see slight shifts. Its up to you to decide what is accurate and where you want the over/under stops of middle grey to lie.

It depends on the scene. EXT daylight might call for higher rating 800-2000ISO to control overexposure/clip. INT NIGHT might want 320ISO so you can clearly know how many stops under you are or how much light to add to keep the picture fairly clean.

Battistella

But the actual shift is minuscule and practically imperceptible.

Dragon is very accurate. I am nit picking.

 

[Elsie N]

Thanks David and Mark. My goal is to shoot available light outdoors including shifts from morning, midday, and evening light. I want to transfer these changes to the audience and I want to shoot in a way to minimalize the amount of color grading in post. (I may change that after seeing all the footage, but for now that is my approach)

 

[David Battistella]

Thanks David and Mark. My goal is to shoot available light outdoors including shifts from morning, midday, and evening light. I want to transfer these changes to the audience and I want to shoot in a way to minimalize the amount of color grading in post. (I may change that after seeing all the footage, but for now that is my approach)

If this is what you want to do then I really suggest leaving your in camera settings (especially WB) fixed. this way you will see the shifts in the light as observed through a neutral WB point. Leave it at 5000K or 5600K all the time.

Battistella

 

[Elsie N]

If this is what you want to do then I really suggest leaving your in camera settings (especially WB) fixed. this way you will see the shifts in the light as observed through a neutral WB point. Leave it at 5000K or 5600K all the time.

Battistella

noted.

 

[David Battistella]

noted.

If you want to contact me off list about this I will be happy to help you through it.

Battistella

 

[D Fuller]

Thanks David and Mark. My goal is to shoot available light outdoors including shifts from morning, midday, and evening light. I want to transfer these changes to the audience and I want to shoot in a way to minimalize the amount of color grading in post. (I may change that after seeing all the footage, but for now that is my approach)

If I were doing that, I'd also want to look very hard at exposure as you go through the day. You will want to modify the ETTR idea a bit. It would be useful to do a few day-long time lapse recordings and watch how the exposure changes throughout the day. Histogram notes, if you will. To get the best-possible images, you''ll certainly want to modify the exposure from what a single-setting time lapse would give you through the day, but being familiar with the differences in what the exposure "naturally" looks like at dawn and noon and in between will help to re-produce the arc of exposure during the day.

The idea of doing this without color grading is a little too Dogma 95 for me, but certainly doing a most of the work in-camera is a very good way to approach it.

 

[Paulo Emílio]

Mark's footage are the cleanest noise. as he said "Noise is directly related to how much light you get to the sensor" maybe 320 iso or 500 is a good start point to protect the noise issue.

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[Elsie N]

If I were doing that, I'd also want to look very hard at exposure as you go through the day. You will want to modify the ETTR idea a bit. ...

The idea of doing this without color grading is a little too Dogma 95 for me, but certainly doing a most of the work in-camera is a very good way to approach it.

David Fuller, I'm really looking for consistency across all shots and I think ETTR would give me that consistency across two cameras. It would also require less time spent in trying to ensure each camera is identical.

But as you suggest, total lack of post and color timing would be folly. So, I'm thinking by shooting a simple ETTR would give me a little latitude to get footage from two cameras and two points of view to look in sympathy with one another, but not identical? Hearing from both David and Mark that color fidelity remains throughout the range, ideally I would like to put a single curve on all the footage and keep the differences in time of day noticeable. And still leave me the option of making a part of a scene "pop" for dramatic purposes.

 

[Mark L. Pederson]

maybe 320 iso or 500 is a good start point to protect the noise issue.

You can get a super clean, noise free image at ISO 800 if you let enough light in via your aperture

People seem more obsessed with what ISO setting to select on the camera - as opposed to being a bit more obsessed with MEASURING LIGHT and/or CHOOSING AN EXPOSURE METHOD. Just looking at a monitor output from a RED camera - which is NOT even a full debayer - is NOT a good enough "EXPOSURE METHOD" if you want an optimal image.

There is no "right" or "wrong" exposure method - light meter, histogram, goal posts, etc. - as long as you understand the fundamentals beyond - "set the ISO and look at the monitor".

 

[Jeremy Hildebrant]

Same old discussion even with Dragon huh....

 

[Mark L. Pederson]

Same old discussion even with Dragon huh....

Sadly ... yes.

In this WYSIWYG world ... the basics of photography and cinematography seem to be skipped by many.