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Weird sensor stuff A7rII


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I am getting these weird streaks in some pictures and a line across the middle of the pictures. Wondering if anyone else has run into these issues? The streaks seem to happen when looking into a bright light source. My guess is a bad sensor and I am noot looking forward to peering into the Sony customer service department. 

 

 

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Very interesting.  Does it only show up when shooting into a bright light in an otherwise very dark scene? Were the images shot in RAW? Because I wonder if it is some sort of posturizing caused by an 8 bit capture using jpg format. Or even Sony's compressed RAW.  If so maybe the soon to be release uncompressed RAW will fix it.

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given the venues is it possible that the sensor was exposed to a laser? i know the samples look different than what seems to be happening to yours but I am no expert when it comes to what happens to a sensor that has been hit by a laser. 

 

 

http://photofocus.com/2013/09/14/beware-lasers-can-kill-your-cameras-sensor/

http://petapixel.com/2013/07/13/video-20k-cameras-image-sensor-fried-by-a-concert-laser-in-just-seconds/

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I had such banding with my A7 when I heavily pushed (+4EV or more) high iso files in post. With the A7RII I didn't see that, but I switched at the same time from LR to C1 too.

 

May you show us a jpg of the unprocessed RAW or try to copy your processing in C1 to see if it is a conersion (not camera) issue?

edit: oh and it would be good if all the exif infos are with it too... :)

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Hello folks, I am new here and it looks like a great place to learn about my new cameras.

 

In the concert shots I don't have an answer (never shot a concert or a laser) but in the video of the truck it looks like the shutter speed is too fast and doesn't sync with the LED lights on the truck.

If you look closely and stop the video you can see the banding is only in certaiin areas. The headlights of the truck are not affected by the banding cuz they are not LED.

Sometimes in car commercials, you can see a similar thing happen in slo-mo footage shot at a high shutter speed. The DRLs wil pulse because they are LED not syced with the camera.

A slower shuter speed will usually fix this. 1/30 could work, but itis visible on the EVF or monitor. HAppens sometimes with Flourescent lights too.

If this isn't what you were talking about....Oops!

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I remember reading about this somwhere. Something that you need to turn off like Silent shutter or eFront curtain shutter. Just have a look

 

Try this suggestion first, the electronic shutter is known to cause some similar effects (IIRC its a documented limitation too).

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I think both the shutter speed and electronic shutter are important and can have a effect with digital lights that pulsate.

 

Unfortunately it is just one of those limitations we will have to find a way around. One of the prices we pay for in the advance of technology.

 

It is almost similar to photographing a TV. Your shutter needs to be slow enough to get a full scan for proper exposure so as to not get banding.

 

Especially if your camera is fine photographing everything else with no problem I realy dont think it is a camera problem but rather a light problem.

 

I am also a switcher from Canon and have even seen inconstant exposures on my Canons shooting on stage where digital lighting is used.

 

Just a matter of shutter speed being to high for the pulse of the electronic lighting.

 

Must say, the learning curve on the A7Rii has been steep. Absolutely worth while, 

 

I am extremely happy with my purchases.

 

My Canon bodies are on the way out.

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The video posted is showing merely pulse width modulation of the LEDs. Simply put, the LEDs are flashing to decrease their observable brightness. Normally we wouldn't be able to detect this with the naked eye, however our cameras are recording much differently than we see. 

 

Regarding the pictures, I'm going to guess it has to do with a similar flashing effect and rolling shutter (each line of pixels read subsequently). If we had global shutter (all lines read at once) I'm guessing the effect would disappear on your pictures. It's telling that there's a pattern to the banding as well, as this would be expected with width modulated light sources.

 

Basically it all boils down to how the light sources are controlled. In these samples, especially the video, it seems the quick flashing lights are affecting the readout because they're faster than the sensor. 

 

With all that being said, do some tests on your own with similarly contrasting lights. Make sure you know the quality of the light (no led or fluorescent). If it persists, by all means contact sony.

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