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Hot/Stuck Pixels (FPN) on Dragon

A

Andrew Allsbury

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Hey guys, so over the 4th of July I shot several different timelapses of the night sky, lakes etc. Upon further inspection of the footage I noticed that everything I shot at 1sec exposure or longer (with frame summing) had several static pixels, some red, some green, etc, speckled throughout my footage In my opinion the shots were pretty much ruined by this abnormality. Upon returning home I re-blackshaded my camera and did some tests with the lens cap on, behold I still have some form of fixed pattern noise that is very noticeable, especially at high ISO. The problem does not seem to occur at normal shutter speeds. Below I have linked to an example r3d shot at 1fps/1sec, please check it out and let me know your thoughts.

ALSO
In all cases both T/E were green and ready to rock.

Download
https://drive.google.com/file/d/0B077sOfEkEI2eWE4cHktZVB3RGM/view?usp=sharing
 
I blackshaded for 1sec shutter which I'm pretty sure is as long as you can go.
 
Is anyone else seeing results like this?
 
Anyone from RED that could chime in would be awesome.
 
Hi Andrew, sorry to hear this...

I rented a Dragon for a job in India recently which had a stuck pixel too...

Blackshading (several times and at different settings) didn't help at all...
 
Thanks for the input Tommaso, good to know its not just me. Were you experiencing the stuck pixel at all shutter settings or just during long shutter?
 
Hi all! Same problem!

I never had the necessity to write on the forums because there are so talented people here tha resolves everything! But now I am very concerned about my camera.
I had a Scarlet MX and the image was very clean when I blackshaded the camera to the target exposure. With my Scarlet Dragon I have the same issue like Andrew. The image has hot/stuck pixels as if you don't blackshade. In addition, the compression furher 8:1 is very bad (lot of noise even on middlegray areas) and when I put the ISO to 12800 the noise pattern is constant but It appears some fluctuation on the image that I never notice with the MX.
I am running some test to sent to RED, I don't know if its my camera or the dragon sensor nature... Most of redusers here are getting stunning clean images!
 
I get similar pixels. When you see a down-sampled (say on my 1080p monitor), you can't really notice them, but make the picture 1:1, and look at the tree. Several red, green, and blue stuck pixels.

https://db.tt/Ly35Xiw9
 
Exactly Adam, It's the same result as you don't do correctly a blackshade on the MX. For example, blackshade to 1/50th sutter and do a 1fps 1/1th timelapse you get those pixels.

Anyone knows how this can be solved? (don't say in post please! :) )
 
Wow, looks like other people are also seeing this issue, could we get some input from a member of the Red Support team?
 
I find it extremely hard to get a clean back shade when trying to shoot 1fps at 360degree shutter. The Dragon seems to do a bit better then MX. Perhaps try one at 1fps 270degree and see if that works any better?
 
I will give 270 a shot, but my MX never had problems like this, blackshades were always totally free of fixed pattern noise or pixel issues.
 
Hi Andrew,

I notice that the problem not only appears on long exposures. Even with a good blackshade, on 1/50, on 100% magnify with the focus assist I can see white stuck pixels. I shoot a lot with the MX and it is cleaner than the dragon on "technological terms".

I have the Scarlet Dragon and with the handicap of worst compression ratios I am very unconfortable with the results that give me the dragon sensor compared to the MX...
 
No one from Red has chimed in on either this post or the one under the Problems section...guess I'm going to have to reach out the old fashioned way.
 
Rubén Molina said:
Hi Andrew,

I notice that the problem not only appears on long exposures. Even with a good blackshade, on 1/50, on 100% magnify with the focus assist I can see white stuck pixels. I shoot a lot with the MX and it is cleaner than the dragon on "technological terms".

I have the Scarlet Dragon and with the handicap of worst compression ratios I am very unconfortable with the results that give me the dragon sensor compared to the MX...
Click to expand...

All this sounds very wrong, and I would suggest you send an RMA note with R3D examples and logfiles to RED.

Now, shooting at 12800 ISO is one thing...
But what you describe here is not "Normal" Dragon behaviour to me.

Have RED look at something

(Nope, I am not "someone from RED")
 
Thanks Gunleik, I will reach out to Red and send over a sample for them to look at. I agree, I can't believe that this would be normal behavior under any circumstance.
 
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