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Scarlet ISO's and Noise

Roshdi Alkadri

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There's common talk on the web about the Scarlet X being noisy past 800 ISO and something about the 800 being the "Sweet Spot". I'm wondering if someone can confirm the ISO capabilities especially in low light please.
 
I would like DXO labs or imaging resource to put the camera to test, as if it was another still camera.
-Les
 
I would like DXO labs or imaging resource to put the camera to test, as if it was another still camera.
-Les
A test, some low light footage at various ISO's would be good. Since the Scarlet X has the same MX sensor as the Epic, i'm wondering where these users who are commenting on the ISO's get their info from
 
A good way to look at it is "How do I expose my films"

There is a goalpost on the left side of the histogram that tells you how much of the frame is "noisy" - there is also a similar goalpost on the right for overexposure that tells you what is clipping.

Generally if you are in between the goalposts you are "good". I've rated things up to ISO 2000 on the MX sensor - and this was before 16 bit depth of Scarlet and Epic.

If I have time I will post an example of how this all works.

If you turn the camera on, point it at something and shoot at ISO 2000 and then bring it into the computer and render it out without adjusting your curves or anything then you might be "unhappy".

Scarlet and Epic are cameras that let you work with a "Digital Negative". Half of the process is the PROCESSING of the digital film to yield the results you are seeking.

Its not One button kind of "video" shooting.

Hope that makes sense and helps.
 
A good way to look at it is "How do I expose my films"

There is a goalpost on the left side of the histogram that tells you how much of the frame is "noisy" - there is also a similar goalpost on the right for overexposure that tells you what is clipping.

Generally if you are in between the goalposts you are "good". I've rated things up to ISO 2000 on the MX sensor - and this was before 16 bit depth of Scarlet and Epic.

If I have time I will post an example of how this all works.

If you turn the camera on, point it at something and shoot at ISO 2000 and then bring it into the computer and render it out without adjusting your curves or anything then you might be "unhappy".

Scarlet and Epic are cameras that let you work with a "Digital Negative". Half of the process is the PROCESSING of the digital film to yield the results you are seeking.

Its not One button kind of "video" shooting.

Hope that makes sense and helps.

All the info is appreciated. There is no doubt that a lot of footage has to go through the "processing" or "grading" stages.

When the Red and then the Epic came out, there were various tests and footage posted proving how well the camera's performed under low light situations especially night time, and the classic signature footage of the lit candle and cigar at various ISO's including 3200 ISO

I was hoping to see something similar with Scarlet.
 
At the same ISO and compression level, Scarlet and Epic should be identical.

I've used the Epic for several weeks now and it is incredibly clean, espeically coming from the M sensor and being rated at 320 for so long, I found it incredibly refreshing.

Yes, it is not difficult to introduce noise in some situations, but there is no set rule such as "anything above 1600 will be noisy." Every situation is different and you may find you get noise at 1200 in some situations and don't get noise at 2500, all depends on the environment so be careful not to make any across the board decisions about what the camera does as there are so many variables involved.
 
The ISO on Red Raw files is metadata. You are not actually adjusting what the sensor is ingesting by increasing or decreasing the ISO, only how that raw data is being processed and displayed.

This isn't an abnormality. With film stock, you can only change your ISO if you physically use different film. With digital cameras, you can only truly change the ISO range of the sensor is you physically change out the sensor system (which is not practical). But since you can *kinda* change the ISO by changing the metadata of how that sensor input is changed, all digital camera manufacturers allow you to do that. But you still aren't changing what the sensor sees, just how it is interpreted. The sensor still has the same maximum and minimum light response points.

Red, however, is just more open and upfront about this, since they give us access to the Raw data and raw metadata.

800 will always be your sweet spot for the MX sensor, with about 6.5 stops in either direction (both brighter and darker) that read correctly.
 
Thanks for all the helpful info guys, i guess you can never rid of all the haters out there towards Red and misrepresenting the information. Looking forward to it.
 
I believe Gunleik has posted that on the forums in the past; it helped me wrap my head around how the sensor works.

I can tell you from experience, our camera was used on a shoot, and the ISO was cranked up to around 125, the image properly lit for that. No one on set at the time understood that this is just metadata. So the bright parts of the image ended up WAY overexposed, and we have chunks that are just blown out.

This is typically the type of thing that, once you understand how it works, and concede that all changes to brightness will be made by changing the amount of light and the aperture (i.e. the physical things you actually can swap out), it usually isn't a problem.

Usually. It could be a problem if you're shooting a concert and have no control over the lighting. Certainly within the realm of possibility, and there are other situations along the same lines. But you have to remember: no other digital camera can truly change ISO either. It is a disadvantage to Digital, not a disadvantage to Red.
 
Major difference between Red and almost any other still or video camera out there. Changing ISO does not by itself change what the camera records. Only light, aperture, frame rate, and shutter speed/angle directly affect recorded raw exposure. Most cameras apply some form of gain or processing to the sensor output before recording as ISO speeds increase. Video cameras typically apply a lot of processing to high gain image recordings.
 
ISO800 is definitely the safe bet for perfectly useable footage sans tweaking in post. Anything higher and I think even the most forgiving person will still feel the need to massage the footage to get a usable image. Also, rule of thumb, the blue channel is the one that needs help the most.

The good news is, with 4k, because you downscale to delivery formats (which is most likely 1080p) you can get away with fairly strong noise reduction without losing noticeable detail. Plus, REDs do a pretty good job of holding tonality (skin tones specifically) even when the images starts to degrade. Other tricks, like adding film grain to mask the noise and make it consistent grain, can only improve your mileage.

Go check out Gunliek's thread about 'what you can do with Scarlet'. Take his T11 shot into RCX and raise the ISO to 3200, then use curves and such to try to make it as clear as possible. That's where I found the breaking point to be for my taste (with the aim of going to 1080p Blu-Ray... if you're going to web, you could probably get away with ISO6400). Because it's metadata, you actually have to start with an under exposed image before you actually start to see grain... Otherwise all you'll be doing is increasing the "ISO" and reducing the curves/brightness to bring it back down (which is equivalent to just lowering the ISO to its starting point.)
 
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