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Horizontal Band in footage - Help please

Jordan Buck

Jordan Buck

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Has anyone experienced this before?
It seems to be happening at 4K 100fps and 90fps and then at 200fps it gets bigger...
I am really disappointed right now - Saw this on the screen earlier and my AC assured me it was a cabling issue, yet here I am staring at footage with it on it.
This is my first shoot with a camera bought second hand. All the test shots I had done came out clean and fine even within the same settings? What has changed?
I have now just done a black shade and it seems to have disappeared - but surely black shading cant affect something as severe as that?
I am really freaking out right now.

Image compression isnt helping here... but hopefully you can see what I mean

How do I upload an R3D file?

Hopefully someone can shed some light on this for me.

A001_C053_02172V0000000_zpsad125807.jpg

A001_C055_0217VB0000102_zps29a04c23.jpg
 
I've seen a similar issue when shooting at 4k or 5k 120fps. It would only happen at 120fps and only at resolutions of 4k and greater. In our case we were using a 120fps (1/240) manually saved black shade setting and I know we did the black shade setting at 3k 120fps (1/240), but I can't say one way or another if that was the cause. I didn't think resolution mattered when doing a black shade calibration, but maybe it does?

In our case the line was extremely faint, only noticeable when we pushed the ISO up to 6400+.
 
I just did a quick test... I reran the blackshade calibration at 5k WS 120fps (1/240) and the horizontal band is still there. But I also noticed that it goes away when I adjust the FPS from 120 to 120.83 (I'm working with 24fps Project / Time Base).

I then played around with the settings some more and I found that while it's not visible at 3k 120fps (as previously noted), it is visible at the following FPS @ 3k: 125, 144 & 150.

What's more, it seems to "jump" around at varying heights dependent on the FPS.

By the way, I'm running all these test with a lens cap on and the ISO at 12,800 - so even though this seems to be related to the FPS this isn't a light flicker issue.

I'm running firmware v4.0.12.
 
So if this is something you are seeing as well - what am I/WE/THE CAMERA doing wrong? or is this a software issue, I mean this shouldn't happen obviously, I have a bunch of un usable shots now as they are all hand held and the band moving with the image is incredibly distracting.
Have you taken your camera in? or just left it and kept shooting?
 
Ran the firmware update (v5.1.38) and that seems to have solved it for my camera. I also ran a black shade calibration after the update and both before and after the black shading it was working fine.

I've tried multiple resolutions/FPS combinations in both 23.98 and 24 Project Time Base, but I can't replicate the problem any longer (which is good).

I wish my findings could also magically replace your footage! :)

Have you tried doing a center extraction (a la Fincher) on any of the shots? Hopefully you'll be able to find a way to save at least some of them.

Cheers,

-Brad
 
Bit of a strange one. Did you black calibrate before the shoot? Could there have been a slight light leak? Or was the ambient temperature for the shoot very different to the temp during the black calibration?

You should also speak with your Bomb Squad rep and/or raise a support ticket.

As Brad suggested, you could centre crop.
OR you could go 2.4:1 aspect ratio and letterbox so you retain horizontal resolution, but pan & scan the unaffected part of the frame down into the letterbox (so headroom stays correct).

Did the effect stay fixed relative to the frame, and did it stay constant until you changed resolution & framerate?

Hard to tell from stills, but it looks like a band where the brightness is raised. With luck you may be able to selectively mask the band and bring the brightness down to match the rest of the frame in your NLE, or After Effects or similar.
 
This definitely seems to be related to black shading more than anything else. I don't think it could be light leak or anything of that nature because I can literally watch it appear and disappear as I cycle through the FPS options, and I'm doing this with a lens cap on.

After updating the firmware it went away, but I was able to make it reappear by black shading for 24FPS (1/48) and then shooting/previewing at 120FPS (1/240). But as long as I switched back to the saved 120FPS (1/240) black shading calibration everything was fine.

I agree with you Eric that it's hard to see the problem in his still images, but since I know what to look for I can tell it's there. Its basically the bottom 10% of frame that's the problem and honestly its looks like that part of the sensor just doesn't get the proper black shading or something to that effect, it seems to have a slightly different black point or gamma.
 
So I spoke to a very helpful gentleman by the name of Callum at RED here int he UK and he is going to have a look at some of my R3D files and a log file etc. just to check everything with the camera is in order.

There was a temperature change - location change - and day change, previous black shade had been done inside on a 9 degree cels day - and this was an outside shoot at about 4-6 degrees in the rain.

I know I should of blackshaded but I wasn't aware that it would really make THIS much of a difference, to my understanding it was just affecting the nature of grain etc. I will most definitely be black shading a lot from now on.

Callum at RED almost cut me off before I said black shading with the answer of that so that makes me feel like we are on the right track, I have a shoot on thursday so just want to make sure the camera is full working for that.

I have a feeling if I matte the bottom 10% of the screen and grade the blacks down I can get it to match - at least thats what I am hoping.

I will let you guys know as it develops and if I can force the issue to happen again to see what its origin is.

Slightly knocked my confidence in my new camera - so want to go out today and shoot some nice images to get my red buzz back.
 
You might want to try the situation I outlined before, just to see if you can replicate the same results and then pass that info on to the person you're in contact with at Red.

Here's exactly what I did:

• Black shade at 24fps - 1/48th
• Change frame rate to 120fps - 1/240th (you should see the bar)
• change frame rate to 120.83fps - 1/240th (no black bar)
• save the black shade 1/48th setting to ssd
• re-black shade at 120fps / 1/240th (the bar should go away)
• switch back and forth between the black shade settings to see the bar appear or disappear

I just think it might be useful for Red to know if this problem is repeatable, or if its just the odd one or two cameras – yours and mine unfortunately. :)
 
I often had this line ..
usually I bring the camera to 51c in adaptive and do calibration,
should disappear.
 
Can you expand? Not sure what you mean by adaptive mode?

This issue is still happening but now only at really high ISOs

Got a trip to RED on Monday to check it all out.
 
He's referring to the fan settings, 'Adaptive Quiet' seems to be the most popular choice here on the forums, but it's not the default so you have to make that change via the menus.
 
I use adaptive mode all the time...works flawlessly for me. Keeps the temp locked.

Regarding your problem:
I set my adaptive mode setting to 60 degrees. Let the camera warm up to that temp, then do a blackshade at the frame-rate/exposure you're wanting to shoot it. Make sure the body cap (don't blackshade with a lens attached as some lens caps don't actually keep all the light from hitting the sensor) is attached. After the blackshading process is complete, with the body cap still on, crank your ISO all the way up to 12,000. You should see an even noise pattern. If not, then there is definitely something else going on.
 
I just had a look at setting the adaptive fan and I couldn't find the option - I think im running a really old firmware 4.0.10?
Transfer of ownership hasn't completed yet and I dont have a log in for red so cant downloaded latest firmware, I would like to give it a go to see if that clears up the problem.

Chris - This is exactly how I had blackshaded, I even re did the test and covered all the ports with a black bolton to ensure no light is coming through - I am certain its a software issue as the band changes in thickness between 100fps and 120fps Its an incredibly fustrating situation, but so far all I can say is that RED have been very helpful and are helping me find a solution.

Also thank you to those who have posted in this thread - much appreciated.
 
I see this line from time to time in darker shots. Wasn't too concerned though because the naked eye can't see it (at least in my experience).
Oddly I noticed switching from back and forth from default black shade to a preset black shade got rid of it... No idea why that worked though.
 
Jordan,
is typical problem not good blackshading...
I too have had the same thing years ago and then I resolved as I have explained.
see post from years ago.
http://www.reduser.net/forum/showthread.php?81001-HELP-ME-GUYSSS-PROBLEM-WITH-NEW-FIRMWARE-3-2-16

I suggest you do these tests several times.
Does not always work the first calibration.

Adaptive mode between 49-51 degrees, not beyond. It works best if you make 49 degrees.
just finished off the camera, wait a few seconds and then turn it on again ... check.

Retry maybe by moving only a few degrees .. until that works.
 
Thanks Luigi,

It seems like a few people have had the problem,
I am heading to RED on Monday and dont have a shoot till next week so im not panicking and it actually doesn't show up on any shots now just with the port cap on and ramped to 128K ISO.

Just one of those things I would rather not see to make me feel confident shooting you know.
 
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