Very High Red-orange Noise Levels Without Black Shade

[Daniel Soderberg]

Anyone else notice crazy noise levels on Dragon when first turning on and also when warmed up without doing a black shade?


I've attached two samples. Note that they are both ISO 4000. The first is without black shade, the second is with black shade at "current exposure/frame rate".




I tried a regular black shade (the other option that is not "current exposure") and the noise levels got MUCH worse which is also weird.




On the upside, the noise levels are insanely low with a good black shade. The downside, they are very high if you don't have time to black shade. And seem to be very non-symmetric having much more noise on left side of sensor.



Also noticed that on the onboard monitor on camera, the noise looks about 3x as bad with crazy flickering (in luminance) in the noise which looks very bad... Not sure why it didn't carry over when uploaded to Redcine. Scared me for a minute.


(Tried to upload R3D but can't on Reduser which is really odd)

Anyone else have similar findings?

http://soderbergfilms.com/DragonCold.png
http://soderbergfilms.com/DragonCaliberated.png

 

[Michael Dalton]

Daniel, YES!!!! Got the same thing. I was a bit concerned too, but I think all is good now that it is black shaded. Also there were a lot of fixed noise pixels, but again, that cleared up.

 

[Stacey Spears]

When you first turn the camera on, especially when really cold, you can see noise on the LCD. As it warms up, the noise fades away.

On the upside, the noise levels are insanely low with a good black shade. The downside, they are very high if you don't have time to black shade. And seem to be very non-symmetric having much more noise on left side of sensor.

I usually only black shade after a FW update. One time I did notice a big red pixel that was not there the day before, which freaked me out. It was gone after a black shade. That is the first, and only time, I have black shaded outside of a FW update. Other than for longer exposures, etc...

 

[Daniel Soderberg]

Michael, yeah I forgot to mention that too. Occasionally there are a couple frames where very bright single noise spots pop up which to the naked eye, appear like white film scratches/dirt sort of thing. A little concerned with these as they did carry over to Redcine. Maybe I'll upload one of those frames too.

 

[John Marchant]

Those little white specks are hits on the sensor from charged particles - they happen to all cameras, but the more sensitive they get the more you'll see it

 

[Jacobo Martinez]

I still don't have my dragon, but I read that now when you finish the blackshade process, it is not applied automatically like before, now you have to manually apply the last user blackshade because now you can store up to 4 user blackshade. Be careful.

 

[Brian Merlen]

Whats the black shade time duration for Dragon...mines in this week but was wondering how fast it is if its going to be important to a lot time for it to avoid such IQ issues as listed above... thank you!

 

[Kyle Wright]

Whats the black shade time duration for Dragon...mines in this week but was wondering how fast it is if its going to be important to a lot time for it to avoid such IQ issues as listed above... thank you!

I think I clocked mine at right about 12 minutes.

 

[Matthew J]

I still don't have my dragon, but I read that now when you finish the blackshade process, it is not applied automatically like before, now you have to manually apply the last user blackshade because now you can store up to 4 user blackshade. Be careful.

Where did you read that because I have not found that to be true.

 

[Brian Merlen]

maybe depends what firm ware your on? no clue...

 

[Steve Murray]

1. You should be Black Shading fairly often. Especially for slow frame rates and large temperature changes.
   
   From the manual:
   
   CALIBRATION CAPTURE (BLACK SHADING)
   
   
   1. Ensure that the camera reaches the temperature that you want to use for your shoot.
      
   2. Set the exposure to the exposure you want to use for your shoot.
      
   3. Before you calibrate, ensure that the sensor is as dark as possible.
      • ‒ Preferably, take off the lens, and install the lens mount cap provided by RED.
        
      • ‒ If you cannot take off the lens, put a lens cap on the lens. (Not all lens-caps completely block IR. Lenscaps are made to protect the lens, not necessarily to block light.)
        
      • ‒ If possible, use a dark room.
        
      • ‒ Just closing the iris is NOT sufficient.
        

From the PDF I give those who rent:

Black Shading

(1) Attach the Body Cap to your lens mount and secure the cap with the locking collar on the mount.


(2) Place your camera in a dark place or cover your camera with opaque fabric. Do not cover the vents.


(3) Power up the camera using A/C Power. Black shading currently takes 12-14 minutes.


(4) Wait for the camera to come up to operating temperature. Usually 10 minutes.


(5) Set your frame rate and shutter speed or angle / degrees to the project that you are shooting.


(6) Begin Black Shading Calibration.

After it completes you may want to verify things are okay. Leave the Red Body Cap on and crank the ISO up to 12,800 and make sure your focus assist tools are turned off. What you are looking for is an even but noisy black field. If for some reason it is not, light or IR has some how leaked in. And you will need to redo it.

Black shading is required:

(1) After upgrading the firmware.

(2) When there are big ambient temperature changes on set.

(3) For using slow shutter speeds (less than 1/15[SUP] th[/SUP] sec.) or after using very fast shutter speeds (1/1000[SUP]th[/SUP] +)

Black shading (Current FPS/Exposure) is intended for slow frame rates and long shutter speeds.

 

[Mike P.]

I noticed the same thing and thought I'd done the blackshade wrong.

What's frustrating is the "default-BS" blackshade making it *more* noisy?... But yeah, I noticed the same thing and the DOP is sticking with Alexa as a result.

 

[Brian Merlen]

I noticed the same thing and thought I'd done the blackshade wrong.

What's frustrating is the "default-BS" blackshade making it *more* noisy?... But yeah, I noticed the same thing and the DOP is sticking with Alexa as a result.

Ouch... Yea I suppose with more sensitivity comes more black shades, makes sense... 12 minutes isn't so bad if it can avoid this, but I can see how if your frequently changing settings you could slow your days down with constant black shades... Now that it can supposedly store 4, probably best to do a prep day and do the black cals for 4 different settings maybe and then you can save time on the production day? Backup mag for even more black cals if your OCD about it, or super high end... Maybe thats what I should get into, selling used mags with pre determined black cals at many settings, filled all the way 512GB mini mags lmfao! thats a lot of 12 minute cycles I could save people!!!

PS excellent Pdf you copy pasted above

 

[Michael Dalton]

Michael, yeah I forgot to mention that too. Occasionally there are a couple frames where very bright single noise spots pop up which to the naked eye, appear like white film scratches/dirt sort of thing. A little concerned with these as they did carry over to Redcine. Maybe I'll upload one of those frames too.

Yes the fixed noise does cary over into redline, as did my red noise. But they were only low light situations. Outside the camera was fine. I sent a message to Red supper, they messaged me right away with the solution. Fast and simple. I should have run the black shade, but I aired on the side of caution as I have a shoot coming up.

 

[TheBied]

I still don't have my dragon, but I read that now when you finish the blackshade process, it is not applied automatically like before, now you have to manually apply the last user blackshade because now you can store up to 4 user blackshade. Be careful.

This is misinformation.

You store up to 4 black shade maps on Dragon as of the 5.2 beta release. You can also script the 4 black shade calculations in a single run. When scripting the calibration selected at the top of the list will be the map applied after calibration finishes.

Also, the current map in use is shown at the top of the black shade dialog. You can always switch maps under the calibration management tab.

 

[Taylor Morrison]

On my Dagon I noticed today that the noise floor (as viewed at iso 12500) goes up pretty dramatically as you decrease the shutter. Ie at 90 or 45 degrees and decreases at shutters more than 180 degrees. I had an idea to do a black shade calibration at 45 degree shutter at 23.97 fps and then see how that compared to the black shade done at 180 degree shutter. In fact the calibration done at 45 degrees shutter is a lot quieter in terms of visible noise (again viewing at the extreme iso of 12500) even at the normal 180 degree shutter. Should this be expected? any downfalls to this?
Thanks
Taylor

 

[TheBied]

On my Dagon I noticed today that the noise floor (as viewed at iso 12500) goes up pretty dramatically as you decrease the shutter. Ie at 90 or 45 degrees and decreases at shutters more than 180 degrees. I had an idea to do a black shade calibration at 45 degree shutter at 23.97 fps and then see how that compared to the black shade done at 180 degree shutter. In fact the calibration done at 45 degrees shutter is a lot quieter in terms of visible noise (again viewing at the extreme iso of 12500) even at the normal 180 degree shutter. Should this be expected? any downfalls to this?
Thanks
Taylor

Black shading at your current exposure will always yield the best results.

 

[Taylor Morrison]

Thanks Matthew,

Is the increase in noise associated with a decrease in shutter angle to be expected on the Dragon? In other words normal? I understand that I am looking at the extreme case highest iso possible, but nevertheless it is visibly increasing. I had not noticed this on my Epic. None of this I can see being an issue on day to day production. More of my just trying to understand the limits of the new sensor.

Thanks in advance

 

[Charles Bergquist]

With a lot of people getting wildly different results and given that there's "more than one way to black shade a Red", especially with the Dragon now. Does Red have any plans of automating this process to some degree? Possibly sending an alert when shutter has changed or when sensor has reached "shadeable" temperature range, etc, etc, etc. Some automated alerts on the menu might take some of the mystery and maybe some of the misuse out of black shading.

For Example Alerts :

- Temp Change / Blackshade Recommended
- Framerate Change / Blackshade Recommended
- Shutter Change / Blackshade Recommended
- _______ Change / Blackshade Recommended


Also, anytime I get the chance I'm going to advocate for that LCD Flip and Flop.

 

[TheBied]

Thanks Matthew,

Is the increase in noise associated with a decrease in shutter angle to be expected on the Dragon? In other words normal? I understand that I am looking at the extreme case highest iso possible, but nevertheless it is visibly increasing. I had not noticed this on my Epic. None of this I can see being an issue on day to day production. More of my just trying to understand the limits of the new sensor.

Thanks in advance

What you may be noticing in these instances is a slight black level shift which makes the noise floor more or less apparent. Black shading will make sure the black level is at it's optimal level.