Noise FPN, Dead Pixel, Bad LowLight... URSA MINI PRO 4.6K

Hello everyone.
First, I want to apologize for my poor English level, I'm from Spain.

10 days ago I bought a Ursa Mini Pro 4.6k EF in Photospecialist, (Germany) I had been behind this camera for several months and finally, I got the money to have it.

I also bought a Sigma ART 18-35 1.8.

Now, since the camera arrived I have been doing several types of tests, which have left me quite upset, especially when I have investigated on the forum for similar problems.

First, I found that this camera with low light, works really fatal. With ISO 800, I can check in low-light scenes what they call FPN noise, and vertical red stripes. Let's not talk about the ISO 1600, which becomes totally unusable in any low light scene.

I have made two sensor calibrations, and even so, whenever I see a black object in a low light scene, I see noise and strange colors in it. With ISO 800 or 1600.

Today I have made some tests with the lens cap on, and this has been the result, I have been able to observe a fixed white point, before and after the calibration. In all ISO ranges, although in 200 and 400, you hardly notice Is this a dead pixel?

I am somewhat disappointed with the camera, I have read in the forum that there have been units that Blackmagic has sent badly and they have had to change them several times. So I do not know if my unit has been defective. I do not want to spend 2 months without a camera waiting for me to get another one or to repair it, because I need it to work, but I do not want to keep a defective product either.

I really need your help.

Material (Shot specs): The images have been taken directly from my screen (LG HDR 4K), without editing or grading.

https://drive.google.com/drive/folders/ ... sp=sharing

UHD
Prores 422
60 FPS
Shutter: 1/60
Iris: 1.7
False Color
Dinamic Range: FILM
White Balance: 5600K

Any help, please? :/

Sergio, I have downloaded the samples you provided and checked them.

1) I can not see any FPN and only minimal vertical red stripes - on a calibrated screen.
So the first question is how and where did you evaluate this footage? Did you watch it in 1:1 mode or scaled? What screen? Was it calibrated? Does your screen do some kind of pixel enhancement like sharpening (some cheaper LCDs surprisingly do)

2) This camera is not a very lowlight camera - that is correct. But you have to know it does not make use of any in-camera noise reduction. After using NR in post you can get very clean low light shots as long as there was a bit of light involved. The camera also does not have an analog gain stage in its sensor electronics like some other cameras. That means changing ISO just changes the gamma transfer curve (total dynamic range stays the same) but does not electronically boost the signal like a Canon Cx00

3) When looking on footage shot in film log gamma you have to be aware that the blacks are raised. You have to grade the footage so that real blacks are almost black.

4) About the dead pixel - as it is bright it is not dead but stuck. In the case of a stuck pixel some or all of the photodiodes that make up the RGB component that comprise a single pixel in your image become stuck at their maximum value. This stuck pixel can therefore be bright blue, green, or red if only some of the photodiodes are stuck or pure white if all the diodes for that particular pixel are stuck at their maximum value.

I am not 100% sure if you can fix the stuck pixel yourself. It might help to updateto the latest firmware of the camera - some say that during firmware updates stuck or dead pixels get mapped out. If you are already on the latest firmware, you can downgrade to a little older version and update to the latest again.

If that does not cure the pixel problem you will have to contact Blackmagic support.

I fixed my stuck red pixel in Resolve on the Colour Page using OFX/ResolveFX/Repair (or something like that—can’t look now to be sure as I’m doing an all night render of last Friday’s shoot.


Sent from my iPhone using Tapatalk

It's worth mentioned that Blackmagic's camera's don't have any sort of in-camera noise reduction so they can't be expected to be as clean as other cameras which shoot in compressed formats. I would recommend using Resolve Studio's chroma noise reduction or the better option would be to buy Neat Video and make a profile made for your UMP.

Edit: Okay, I'm really bad with repeating things that someone else already said today.

Sergio, I have downloaded the samples you provided and checked them.

1) I can not see any FPN and only minimal vertical red stripes - on a calibrated screen.
So the first question is how and where did you evaluate this footage? Did you watch it in 1:1 mode or scaled? What screen? Was it calibrated? Does your screen do some kind of pixel enhancement like sharpening (some cheaper LCDs surprisingly do)

2) This camera is not a very lowlight camera - that is correct. But you have to know it does not make use of any in-camera noise reduction. After using NR in post you can get very clean low light shots as long as there was a bit of light involved. The camera also does not have an analog gain stage in its sensor electronics like some other cameras. That means changing ISO just changes the gamma transfer curve (total dynamic range stays the same) but does not electronically boost the signal like a Canon Cx00

3) When looking on footage shot in film log gamma you have to be aware that the blacks are raised. You have to grade the footage so that real blacks are almost black.

4) About the dead pixel - as it is bright it is not dead but stuck. In the case of a stuck pixel some or all of the photodiodes that make up the RGB component that comprise a single pixel in your image become stuck at their maximum value. This stuck pixel can therefore be bright blue, green, or red if only some of the photodiodes are stuck or pure white if all the diodes for that particular pixel are stuck at their maximum value.

I am not 100% sure if you can fix the stuck pixel yourself. It might help to updateto the latest firmware of the camera - some say that during firmware updates stuck or dead pixels get mapped out. If you are already on the latest firmware, you can downgrade to a little older version and update to the latest again.

If that does not cure the pixel problem you will have to contact Blackmagic support.

It's worth mentioned that Blackmagic's camera's don't have any sort of in-camera noise reduction so they can't be expected to be as clean as other cameras which shoot in compressed formats. I would recommend using Resolve Studio's chroma noise reduction or the better option would be to buy Neat Video and make a profile made for your UMP.

Edit: Okay, I'm really bad with repeating things that someone else already said today.

I fixed my stuck red pixel in Resolve on the Colour Page using OFX/ResolveFX/Repair (or something like that—can’t look now to be sure as I’m doing an all night render of last Friday’s shoot.


Sent from my iPhone using Tapatalk

Hi guys, the first thing I'm sorry for taking so long to answer, I had to go on a trip.

Thank you very much for your answers and clarifications, the truth is that I was getting a little crazy with this camera.

About the FPN noise, or normal noise (it's something that I was most worried about) I managed to clean it a lot as you said in Davinci Resolve. Even so, this camera is not the best for recording at night, true? I honestly bought this camera, even knowing what I was buying, as an element of "Run and shoot". Even so, at night, is better not to upload ISO 800?

On the white pixel that appeared to me, I could also check some flickeo in some of the clips, (having the latest version). So taking advantage of my 14 days of free return, I took advantage of them and I'm waiting for them to give me back the money to buy another body again. (I hope this comes in right state).

Another question that arose me these days, rolling with a Sony A7 III in some scene, which was splashed water; the Ursa Mini Pro, would be at risk in these conditions, such as rain or snow?

And the last one, is the Sigma ART 18-35mm 1.8 a good lens for this camera? Even if it does not have an internal stabilizer? I use the UMP with a Glidecam.

Again, thank you very much everyone.

Sounds like the ursa mini pro is not the camera you need.

Yeah, I'm not sure of that either.
Even if it has better features for documentaries than it's predecessor, it's not really a run-n-gun camera. There are several features, like autofocus and exposure, which would be better suited with a TV camera in the same price range. The UMP46K is a cinema camera with limited features for documentaries under more or less controlled conditions. Some Sony cameras, like the A7S, are much better at night, for example. The A7S has better stabilisation. Some other Sonys have better AF and more flexible options for AE.

The Sigma 18-35mm is a great lens for that camera, but again not that much for run-n-gun.

I’ve continued to shoot successfully in light rain while trying to protect the lens and camera body neither of which are water resistant. When the rain persists, I shutdown everything.

I’ve continued to shoot successfully in light rain while trying to protect the lens and camera body neither of which are water resistant. When the rain persists, I shutdown everything.

Yeah, I'm not sure of that either.
Even if it has better features for documentaries than it's predecessor, it's not really a run-n-gun camera. There are several features, like autofocus and exposure, which would be better suited with a TV camera in the same price range. The UMP46K is a cinema camera with limited features for documentaries under more or less controlled conditions. Some Sony cameras, like the A7S, are much better at night, for example. The A7S has better stabilisation. Some other Sonys have better AF and more flexible options for AE.

The Sigma 18-35mm is a great lens for that camera, but again not that much for run-n-gun.

Sounds like the ursa mini pro is not the camera you need.

Hi guys, the first thing I think I did not explain myself well in my previous answer, my apologies.

I use the camera to do promotional advertisements in its greater part, also interviews and other type of videos of that type. In which the light is controlled.

With the previous answer I will refer to that I also plan to use the camera for action scenes, outdoors, and perhaps to shoot videos when I travel to a site (I love to take my camera on). I come from a Sony A99, with which you can not control absolutely nothing of the video camera, nor the autofocus, which worked very badly.

To the BM I always add my Sigma 1.8, and my steadycam, the weight is not a problem for me. For what I can not carry incorporated, I do not mind a big inconvenience using my constant.

Above all my big doubt was in its use in low light conditions and the noise that this camera created when the light can not be controlled. And about this, I do not dedicate myself to go at night to record in the city. Above all I mean for example when recording in an interior, with low light. Still, I managed to reduce the noise completely in some low light scenes with resolve.

Thank you so much everyone!