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DRAGON vs EPIC MX Noise - NOT GOOD

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If memory serves me well, it was said that Dragon at 2000 ISO should behave noise wise like MX at 800.

Its te disappointing to see this.
 
Dragon



MX



I don't see the problem with this footage. Developed DragonCoior4 RedLogFilm.

Pat
 

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In the kitchen shot one thing that I am seeing is that there is a more regular pattern to the Dragon's noise. Something I see often in 5D and something I remember from early Red One. It's also something that I had attributed to an improper black shading but could be something else.
 
Just want to be clear - my intention in posting this thread is to improve the situation. Within a minute after firing up my dragon my gut (and the lowlight goalpost) told me something was not right. I owned a r1 M,MX, epic and now dragon. I just want the best images possible.

Brent if you need my assistance with anything that could be helpful I am willing to help in any way I can. I hope this can get figured out soon.
 
Hi guys,

I did a small test this morning. Fresh Black shading. Nikkor 20mm lens (did not even check focus) just did it quick in my office. I am not seeing that clumpy RED channel noise unless I zoom in to about 150-200 percent.

I don't have an MX to do side by side, but basically if you see that noise goal post then the EPIC is telling you that the noise is going to be there. The thing that blew me away the most was that there is a 1 stop noise "threshold" so to speak. It took only one stop (going from 8.0 to 5.6) to eliminate 80% of the noise. That was a surprise to me as I thought it would be much more gradual.

What it means is (and I am talking about how I have to treat my camera today) that if I see that noise goal post, I'm going to to everything to open up or add more light to get rid of it. Of course we all know that in the real world that ain't always possible. If you wide open and the noise goal post is up, it's telling you that there is some noise in that frame.

Underexposure is going to create noise. It's just that simple. As I said in my early findings. Throw light at these sensors and these problems disappear. The first thing I captured on my Dragon was the exact same scene I captured on my MX, a dimly lit church. The dragon far outperformed the MX in that scenario.


My test is so basic.


1. Expose at F8.0
2. Expose at F5.6
3. Expose at F4.0

At F8 the goal post is fully lit-up on the scene. 1:1 crop on the image.

8_0.jpg

At 5.6 80% of the goal post goes away and so does the noise.

5_6.jpg



At 4.0 it's that much cleaner.

4_0.jpg




Here is the link to the R3D's

https://www.dropbox.com/s/aw9ezx7hk68rwuk/3stops.zip

To me, the shot at f4.0 should have no noise at all, none... Nothing is crushed, the noise bar is empty, yet there is noise... This is not right at all...
 
My theory after doing the dynamic range testing is that it looks like the RED files are cutting off the blacks. So "0" has been calibrated down to -.001 or so. As a result you're seeing a less desirable noise structure where the bottom of the noise floor is below 0.0.

When I did long frame averaged takes I would expect the noise floor to "stabilize" somewhere around 0.0001 instead it stabilized at 0 in some places. That's highly improbable that every single frame of 100+ frames is exactly at 0 (the true bottom of the noise floor).

My super hypothetical theory is this. Dragon used to be an 800 ISO sensor. They 'mechanically' tuned down the analog gain by 50% to make it a 400 ISO sensor like MX. This revealed some extra headroom. But in the process the ADCs are now clipping in the shadows. The fix would seem to be to add a little bit of lift prior to debayering to ensure that no data is getting clipped. .
 
My theory after doing the dynamic range testing is that it looks like the RED files are cutting off the blacks. So "0" has been calibrated down to -.001 or so. As a result you're seeing a less desirable noise structure where the bottom of the noise floor is below 0.0.

When I did long frame averaged takes I would expect the noise floor to "stabilize" somewhere around 0.0001 instead it stabilized at 0 in some places. That's highly improbable that every single frame of 100+ frames is exactly at 0 (the true bottom of the noise floor).

My super hypothetical theory is this. Dragon used to be an 800 ISO sensor. They 'mechanically' tuned down the analog gain by 50% to make it a 400 ISO sensor like MX. This revealed some extra headroom. But in the process the ADCs are now clipping in the shadows. The fix would seem to be to add a little bit of lift prior to debayering to ensure that no data is getting clipped. .

In theory that should be easy for RED to tweak right? I mean, each stop down low feels like it has a steep drop off to the next stop instead of a gradation from one to the other. Is that a simple way of stating it?
 
just to add, getting similar noise here. Recently upgraded to Dragon, did a test of Dragon and an MX epic, I upgraded both to current firmware and blackshaded both. Below is a side by side blow-up of a detail- Dragon shot 6KHD with 50mm RPP and Epic-x shot with 35mm 5KHD and physically closer to match frame sizes. Blow up shows more detail in Dragon, but also more noise.....
side-by-side-4.png
 
Well,

I realized I was looking at my footage in 1/8 mode in RCX. At 1/2, the images are loaded with red speckled noise even at all the proper exposure and settings. The noise is consistent across each image. It's just more noticeable in the blacks / shadows.

I've re-opened a ticket with RED about it.

Damn...
 
To me, the shot at f4.0 should have no noise at all, none... Nothing is crushed, the noise bar is empty, yet there is noise... This is not right at all...

You don't look at RAW but at some RG4 curve set to 800 iso. If you push your low lights (the lowest is the blue channel far left in that picture) to the mid grey (like exposing it to 2000 iso) it's normal you'll have some noise even if the goal post says (at 800 iso) there is no noise. Same applies with big color temp changes (like 5500k to 2700).

Pat
 
You don't look at RAW but at some RG4 curve set to 800 iso. If you push your low lights (the lowest is the blue channel far left in that picture) to the mid grey (like exposing it to 2000 iso) it's normal you'll have some noise even if the goal post says (at 800 iso) there is no noise. Same applys with big color temp changes (like 5500k to 2700).

Pat

I know how to process footage lol. Switch to Redgamma 4 and tell me you don't see noise...

Look at the R3D yourself and you will see...
Screen-Shot-2014-06-09-at-1.06.29-PM.png


Even dropping ISO to 250 still shows some noise (although much less for obvious reasons..)
Screen-Shot-2014-06-09-at-1.12.09-PM.png
 
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