Blackmagic Forum

Hello!

I know this has been addressed many times, but this is the first time I'm getting nervous. Because a lot of people get sensor problems in low-light conditions using 1600 ISO, and they either send cameras for an exchange, or get an answer that this is normal.

The problem is - it wasn't on my BMCC till that time. And I really wanna make sure that the camera either faulty or I am doing something wrong. Please check out my footage to clear that out. I attach a clip off the camera AND screen capture of Ultrascope to see the waveform.

The banding and horizontal split line is seen at: 0:02, 0:20, 0:29, 0:44

Camera settings:
Prores 422 HQ FILM compressed as H.264
800 ASA
180 degrees
50mm 1.8

Lighting:
x3 75 watt bulbs

No color correction, pushes or anything. Straight from the camera to Final Cut Pro X.
And I'm really, REALLY sorry for the mess in my room

https://www.dropbox.com/s/8wms8h92l8lf3x8/ultrascope%20capture.mov
https://www.dropbox.com/s/t766cv5p3rs6tb3/banding.mov

Anyone?

Can you explain what it is you are seeing. It's difficult to judge with the camera jerking around so much.

The file you uploaded is a compressed H.264 file. So it's gonna have banding as it's 8bit 4:2:0.

adamroberts wrote:Can you explain what it is you are seeing. It's difficult to judge with the camera jerking around so much.

The file you uploaded is a compressed H.264 file. So it's gonna have banding as it's 8bit 4:2:0.

Well, it's a compressed FILM log, the details arent lost, no shadows pushes, exposure is correct. Why should it have artifacts? I see on BMCC monitor a split line and other nasty things. It shouldn't be there. Its not low light or grading pushed beyond the sensor abillities. You can clearly see that everything is fine at waveform.

I also can'r see the banding...

Here, compare with the banding my BMCC has:
https://www.dropbox.com/s/dcv8xhd9bt7iv ... _C0003.mov

I've got two units showing this already...

Is it more prominent on the monitor then in the footage?

Especially split line and vertical striped noise pattern?

Sent from my Android Phone

MatthijsLiethof wrote:Is it more prominent on the monitor then in the footage?

Especially split line and vertical striped noise pattern?

Sent from my Android Phone

on the LCD, but it's defienetly on the footage.

Please share a dng at iso 800 which shows this problem and provide a few seconds of ProRes Film footage which shows this problem, not transcoded to h264 or web formats.

Tom wrote:Please share a dng at iso 800 which shows this problem and provide a few seconds of ProRes Film footage which shows this problem, not transcoded to h264 or web formats.

and what's the point of that if I was shooting Prores?

it's definetly there on ungraded FILM footage, and not a compression artefacts.

On BMCC I've noticed banding at 180 degree - 24 fps. I usually shoot at 172.8 degree shutter@ 24p with no issues. Test it out first though. Practical light sources could be a factor with your footage but changing to 172.8 should fix it.

This may help also:
http://www.cinematography.com/index.php?showtopic=52927

Going from the thread, not the footage yet, it seems similar to what I am experiencing.

Could you upload a short prores clip and a dng?

Sent from my Android Phone

Nikolay Smirnov wrote:

Tom wrote:Please share a dng at iso 800 which shows this problem and provide a few seconds of ProRes Film footage which shows this problem, not transcoded to h264 or web formats.

and what's the point of that if I was shooting Prores?

it's definetly there on ungraded FILM footage, and not a compression artefacts.

ok then please share a few seconds of ProRes film footage, not transcoded - where it shows the problem.