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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Horizontal Magenta CMOS Lines Continued

Charles Bergquist

Charles Bergquist

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Is anyone else getting these horizontal CMOS lines as much as I am? I've brought it up before on a few threads, Red Support says they're aware of it, and I'm sure they're working on something...but it's on a lot of the stuff I shoot.

I get the noise thing, it's an OLPF, I understand the tradeoffs and it makes sense. This is however really impacting what comes out of the camera, and there really isn't anything I can do except not shoot the way I'd like to.

Here's a few more examples of the issue without a source in the frame to cause the lines, but they're there.

Advice? Thoughts? Bad Sensor?

Also, is anyone noticing a low end gamma shift when in RedLogFilm and at 800 - 2000 ISO on low light stuff? I can post some examples of this issue as well.

Yes, I am properly blackshaded.

001.jpg

LINKS TO JPGS

https://dl.dropboxusercontent.com/u/161718/08282014001.jpg

https://dl.dropboxusercontent.com/u/161718/082820140002.jpg

https://dl.dropboxusercontent.com/u/161718/082820140004.jpg
 
Charles Bergquist said:
Is anyone else getting these horizontal CMOS lines as much as I am? I've brought it up before on a few threads, Red Support says they're aware of it, and I'm sure they're working on something...but it's on a lot of the stuff I shoot.

I get the noise thing, it's an OLPF, I understand the tradeoffs and it makes sense. This is however really impacting what comes out of the camera, and there really isn't anything I can do except not shoot the way I'd like to.

Here's a few more examples of the issue without a source in the frame to cause the lines, but they're there.

Advice? Thoughts? Bad Sensor?

Also, is anyone noticing a low end gamma shift when in RedLogFilm and at 800 - 2000 ISO on low light stuff? I can post some examples of this issue as well.

Yes, I am properly blackshaded.

View attachment 56048

LINKS TO JPGS

https://dl.dropboxusercontent.com/u/161718/08282014001.jpg

https://dl.dropboxusercontent.com/u/161718/082820140002.jpg

https://dl.dropboxusercontent.com/u/161718/082820140004.jpg
Click to expand...


I do not understand where they come from .. there is no 'strong light source !!
Very strange ...
Used Nikon or Canon or pl? have the original R3D?
 
luigivaltulini said:
I do not understand where they come from .. there is no 'strong light source !!
Very strange ...
Used Nikon or Canon or pl? have the original R3D?
Click to expand...

Using the EF mount. I have the original R3D's, if someone is interested. It's not an issue of exposure / blackshading / etc, it seems like a processing or sensor error. This concerns me much more than the noise and I wish there was some official note that they're working on it.

Even street lights and interiors I get the same thing. All different lenses, no filtration, different shutters and frame rates.
 
Charles,

why not put up a few R3ds. Have you filed a support ticket? I've seen it but not in the way you describe.
This is a known CMOS thing but I know you already know that.

Battistella
 
David Battistella said:
Charles,

why not put up a few R3ds. Have you filed a support ticket? I've seen it but not in the way you describe.
This is a known CMOS thing but I know you already know that.

Battistella
Click to expand...

Yeah, support ticket filed a month or two ago and I followed up, Red said they know of the issue and have engineers working on it both times I asked. It just hasn't been announced or addressed the same way the noise situation has been and I feel like it's fairly critical issue. All I can do is post and poll other users when it pops up, and it has come up on literally every shoot that's not in unobstructed daylight.

I'll post some R3Ds later his weekend.
 
I've never seen this on my footage. I do a lot of low light. I'll pay a particular attention to it next time I'm on RedcineX.

Have you had the chance to compare with another Dragon shooting the same scene? What are the conditions to reproduce this problem? I could try to do it. Your picture seams to have lowlight saturated color. Could this trigger the horizontal line?

Pat

Ps: if its only your Cam doing it, you could ask for warranty, there fore its good to know if All Dragon behave this way. I've never seen that before.
 
This is an issue across all mounts, like the flare gate shadow problem. Very bright areas of the screen are produce hotizontal magenta smears against darker parts of the screen. Bright window against a dark room. Tried shooting a cellphone screen against a dark room, same problem.
 
We just recieved our dragon, as soon as we fired it up and pointed it at a bright source on a darker BG we saw the issue. When we brought it into RCX we immediately noticed a magenta cast in the shadows aswell.

The picture is beautiful, I'm sure red will find a solution for both! We are hoping sooner than later!
 
Paul J Steinberg said:
This is an issue across all mounts, like the flare gate shadow problem. Very bright areas of the screen are produce hotizontal magenta smears against darker parts of the screen. Bright window against a dark room. Tried shooting a cellphone screen against a dark room, same problem.
Click to expand...

But those lines don't look like an optical flair due to the mount. More like an electronic problem of the CMO as of old CCDs. I've never seen that before.

Pat

PS: can someone send an R3D with this problem?
 
Pat: It is a sensor problem. Reportedly all CMOS sensors have the problem, all other manufactures offset it by adding green to the artifact so you can't see it without pixel peeping in Photoshop.

I've posted these before. Three images, Dragon/C300/1DmkIV. Only the Dragon shows visible magenta streaks. R3D is included for the Dragon clip.

https://www.dropbox.com/sh/q4j4cnt1gd99b7j/AACQ4iNUw10DO1dAXSq9KEmZa?dl=0
 
Can be tamed quite effectively and without loosing a lot of detail simply by dropping the ISO to 320 and turning on DEB. I know that is not an ultimate "fix" but it does make a difference. looks like it happens about 30ire.

Battistella
 
Lowering ISO is not a real "fix", though. There are input-LUT stuff that keeps the exposure "right", with or without DEB.

You cannot allways tell the DoP to shoot the way "you" would have prefered...
there can be a ton of good reasons for him/her to do otherwise.
 
Gunleik Groven said:
Lowering ISO is not a real "fix", though. There are input-LUT stuff that keeps the exposure "right", with or without DEB.

You cannot allways tell the DoP to shoot the way "you" would have prefered...
there can be a ton of good reasons for him/her to do otherwise.
Click to expand...


Totally agree. I'm more leaning toward strategies. Acknowledge it's there and it can pose a pretty big problem for folks.

Battistella
 
This and the lowlight capabilities are the two things giving me pause on upgrading. Once swappable OLPFs are out, that will solve my first concern, but I would like to see this addressed.
 
Anyone running into gamma shifting issue? This has happened since I've had my Dragon, wondering if anyone else is running into this.

Blackshaded properly, obviously underexposed, but I get this a lot on low-light footage.

It's 180MB ProResHQ file :

https://dl.dropboxusercontent.com/u/161718/GAMMA_SHIFT_6KFF_2000ISO_RLF.mov

I am using 800-2000 a lot in low light situations and it's usable, noisy but usable. I do feel that the Epic was never good past 1280 because of the blue splotchy noise, I have to say with the Dragon they've done a really decent job with it. It's not what was described when they announced it, but the higher ISOs are a lot better than Epic. The mid-range ISOs do have a little more noise than Epic.

Anyway, any thoughts on how to remedy this gamma shifting or whatever it is?
 
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