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View Full Version : Horizontal Magenta CMOS Lines Continued



Charles Bergquist
08-29-2014, 05:34 PM
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.

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

bevan goldswain
08-30-2014, 02:04 AM
I am getting those magenta lines too.

luigivaltulini
08-30-2014, 03:01 AM
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.

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


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?

Gunleik Groven
08-30-2014, 03:19 AM
Have you tried developing wit DEB enabled?

Charles Bergquist
08-30-2014, 10:44 PM
Have you tried developing wit DEB enabled?

Unfortunately, DEB doesn't affect the magenta CMOS lines.

Charles Bergquist
08-30-2014, 10:50 PM
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?

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.

David Battistella
08-31-2014, 12:10 AM
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

Gunleik Groven
08-31-2014, 12:27 AM
I'd like to see an R3D, too...

Charles Bergquist
08-31-2014, 12:37 AM
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

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.

Patrick Tresch
08-31-2014, 03:53 AM
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.

Donald MJ Anderson
08-31-2014, 05:40 AM
Using the EF mount.

Is this just an EF mount thing or is it appearing on other mounts?

Paul J Steinberg
08-31-2014, 06:23 AM
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.

Nathan Apffel
08-31-2014, 08:42 AM
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!

Patrick Tresch
08-31-2014, 08:43 AM
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.

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?

Paul J Steinberg
09-01-2014, 05:59 AM
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

David Battistella
09-01-2014, 10:33 AM
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

Gunleik Groven
09-01-2014, 10:50 AM
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.

David Battistella
09-01-2014, 10:57 AM
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.


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

Battistella

Niko Pueringer
09-01-2014, 04:32 PM
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.

Charles Bergquist
09-02-2014, 01:17 AM
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?

David Battistella
09-02-2014, 02:32 AM
That one is subtle and could almost be a flare. when the bokeh lights on right frame disappear, the shift happens. If this was a studio environment, I would be less inclined to think it's flair, but since it is in a moving car. it could also perhaps be something to do with the slow motion and the shutter speed and angle.

Can you reproduce this in just a normal setting, not on the move?

battistella

Charles Bergquist
09-02-2014, 03:14 AM
That one is subtle and could almost be a flare. when the bokeh lights on right frame disappear, the shift happens. If this was a studio environment, I would be less inclined to think it's flair, but since it is in a moving car. it could also perhaps be something to do with the slow motion and the shutter speed and angle.

Can you reproduce this in just a normal setting, not on the move?

battistella

Yeah I've had this issue since I got my Dragon. I can reproduce it anywhere, but it's random. It's nothing to do with flaring, which is what I thought at first, to me it seems almost power / electrical related. When I first saw it I thought it was lights turning on and off in buildings around me at night. Anyway, just trying to get this out there and see if anyone else has seen this. I opened and filed a support ticket with this and the magenta lines months ago and they said it was being looked into. Now that more people are using them, I'm hoping that it's either common or uncommon and needs to be sent in.

David Battistella
09-02-2014, 07:35 AM
How are you powering? Does it happen on battery and on mains?


i haven't seen this on either. If it persist I'd be thinking about sending it in for a check.


Battistella

Charles Bergquist
09-02-2014, 12:51 PM
Yeah exactly what I thought when I first saw it, but it happens when powered by RedVolt / V-Lock and mains. We use the Redvolts a lot because we're on a MoVI a lot of the time now.

Matthew Riggieri
09-02-2014, 03:16 PM
I would like to confirm that I also see the magenta line issues.


Only when looking at extremely overexposed areas against darker areas. Of course, that is the pretty images, so RED needs to fix this or give us an update on it.

http://clients.digitalcavemedia.com/reduser/A010_c014.jpg

you can download the r3d @ http://clients.digitalcavemedia.com/reduser/magenta_lines.R3D

Arnaud Dumas
09-02-2014, 05:43 PM
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?

We've had the same issue with our Epic-M Dragon. Some kind of strange flicker in the noise/shadows.

Seems to pop up only when doing very low light stuff. I don't think it affect the entire picture as it seems to disappear when we crush the blacks and the noise away. However, it is giving me problems right now on a shot with lifted blacks (and a lot of Neat Video), which would work out fine if it wasn't of this flicker/gamma shift.

We can also clearly see it even more when booting up the camera, before the camera is warmed up, with the lens cap on.
The Touch LCD will show a lot of noise and also what seems like the same flicker, but exaggerated.

Niko Pueringer
09-03-2014, 05:26 PM
Has anyone tried a similar shot on MX? I don't recall this artifact ever occurring on our Epic.

Adam Johnson
09-03-2014, 05:44 PM
I see the same strange flicker on lowlight stuff :-/


We've had the same issue with our Epic-M Dragon. Some kind of strange flicker in the noise/shadows.

Seems to pop up only when doing very low light stuff. I don't think it affect the entire picture as it seems to disappear when we crush the blacks and the noise away. However, it is giving me problems right now on a shot with lifted blacks (and a lot of Neat Video), which would work out fine if it wasn't of this flicker/gamma shift.

We can also clearly see it even more when booting up the camera, before the camera is warmed up, with the lens cap on.
The Touch LCD will show a lot of noise and also what seems like the same flicker, but exaggerated.

Scott C
09-03-2014, 05:55 PM
I don't remember seeing this ever on mx and I shot a ton of low light stuff at concerts in very similar conditions. Would be nice to get some official word on this, I'm a bit concerned.

Charles Bergquist
09-03-2014, 06:34 PM
The flicker is bad but I'm glad I'm not the only one in the boat with the issue and that it's naturally occurring on Dragon.